New Battery Type?

[AS]

Winter is coming and it is time to get the annual Battery / Battery Charger discussion going.
I ran across this ad for a new (to me) battery type. It is a Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2) chemistry and the Ah rating the mfg claims is phenomenal.
Has anybody seen or even used this type already?

http://www.millenair.nl/shop/batteries-electrical-equipment/nmc-batteries/airnergy-14.4v-20.5ah-nmc

Uli
'AS'

[[email protected]]

El jueves, 26 de noviembre de 2020 a la(s) 00:27:24 UTC-3, AS escribió:
> Winter is coming and it is time to get the annual Battery / Battery Charger discussion going.
> I ran across this ad for a new (to me) battery type. It is a Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2) chemistry and the Ah rating the mfg claims is phenomenal.
> Has anybody seen or even used this type already?
>
> http://www.millenair.nl/shop/batteries-electrical-equipment/nmc-batteries/airnergy-14.4v-20.5ah-nmc
>
> Uli
> 'AS'

Yes, i made 3 packs for a guy who owns a discus with a lot of avionics and no place for much batteries.
He is reselling one (in Argentina) because with two has enough power to fly 24h transmitting with the radio.
The packs are made with the same cells that I have on the grasshopper and in most of the electric propulsion projects with the exception of FES that uses KOKAM cells.
The only thing that you need to look up before installing is the compatibility of your avionics with the output voltage.
And of course, taking good care of the packs.

[Richard Large]

At 04:38 26 November 2020, wrote:
>El jueves, 26 de noviembre de 2020 a la(s) 00:27:24 UTC-3, AS
>escribi=C3=B3=
>:
>> Winter is coming and it is time to get the annual Battery / Battery
>Charg=
>er discussion going.=20
>> I ran across this ad for a new (to me) battery type. It is a Lithium
>Nick=
>el Manganese Cobalt Oxide (LiNiMnCoO2) chemistry and the Ah rating
the mfg
>=
>claims is phenomenal.=20
>> Has anybody seen or even used this type already?=20
>>=20
>>
>http://www.millenair.nl/shop/batteries-electrical-equipment/nmc-
batteries=
>/airnergy-14.4v-20.5ah-nmc=20
>>=20
>> Uli=20
>> 'AS'
>
>Yes, i made 3 packs for a guy who owns a discus with a lot of avionics
and
>=
>no place for much batteries.
>He is reselling one (in Argentina) because with two has enough power
to
>fly=
> 24h transmitting with the radio.
>The packs are made with the same cells that I have on the grasshopper
and
>i=
>n most of the electric propulsion projects with the exception of FES that
>u=
>ses KOKAM cells.
>The only thing that you need to look up before installing is the
>compatibil=
>ity of your avionics with the output voltage.
>And of course, taking good care of the packs.
>We have been using an NMC 20AH battery in our Arcus for the last year
running LX9000 F and R plus a radio and so far our longest flight has
been 7 hours bat then 14V so looks like 8 Hours possible, our 12v
LiF3PO4 only gave us 3.5Hrs, take care as initial voltage is approx 16v

[John Galloway[_2_]]

On Thursday, 26 November 2020 at 12:30:06 UTC, Richard Large wrote:
> At 04:38 26 November 2020, wrote:
> >El jueves, 26 de noviembre de 2020 a la(s) 00:27:24 UTC-3, AS
> >escribi=C3=B3=
> >:
> >> Winter is coming and it is time to get the annual Battery / Battery
> >Charg=
> >er discussion going.=20
> >> I ran across this ad for a new (to me) battery type. It is a Lithium
> >Nick=
> >el Manganese Cobalt Oxide (LiNiMnCoO2) chemistry and the Ah rating
> the mfg
> >=
> >claims is phenomenal.=20
> >> Has anybody seen or even used this type already?=20
> >>=20
> >>
> >http://www.millenair.nl/shop/batteries-electrical-equipment/nmc-
> batteries=
> >/airnergy-14.4v-20.5ah-nmc=20
> >>=20
> >> Uli=20
> >> 'AS'
> >
> >Yes, i made 3 packs for a guy who owns a discus with a lot of avionics
> and
> >=
> >no place for much batteries.
> >He is reselling one (in Argentina) because with two has enough power
> to
> >fly=
> > 24h transmitting with the radio.
> >The packs are made with the same cells that I have on the grasshopper
> and
> >i=
> >n most of the electric propulsion projects with the exception of FES that
> >u=
> >ses KOKAM cells.
> >The only thing that you need to look up before installing is the
> >compatibil=
> >ity of your avionics with the output voltage.
> >And of course, taking good care of the packs.
> >We have been using an NMC 20AH battery in our Arcus for the last year
> running LX9000 F and R plus a radio and so far our longest flight has
> been 7 hours bat then 14V so looks like 8 Hours possible, our 12v
> LiF3PO4 only gave us 3.5Hrs, take care as initial voltage is approx 16v

I'll stick with LFP batteries. Apart from the price there are considerable human and environmental costs of current cobalt production, most of which comes from the DRC. Its no surprise that e.g. Tesla are trying move on from cobalt in their batteries.

[Robert Danewid[_2_]]

I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.

/Robert

[AS]

On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
>
> /Robert

So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
That would lead me to more follow-up questions for the experts:
- what would happen if this battery was charged with only 15V?
- if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
- I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?

Thanks for any constructive replies.

Uli
'AS'

[Eric Greenwell[_4_]]

AS wrote on 11/26/2020 8:59 AM:
> On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
>> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
>>
>> /Robert
>
> So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
> That would lead me to more follow-up questions for the experts:
> - what would happen if this battery was charged with only 15V?
> - if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
> https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
> - I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?
>
> Thanks for any constructive replies.

The voltage regulator might cause radio and other interference, adds complexity, and one more
item to fail, possibly damaging the devices it was supposed to protect. There seems to be no
sufficient reason to consider this chemistry, compared to LiFe batteries, unless you are space
limited, due to higher cost and risk of over-voltage.

Is battery space insufficient on your glider?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1

[AS]

On Thursday, November 26, 2020 at 1:02:00 PM UTC-5, Eric Greenwell wrote:
> AS wrote on 11/26/2020 8:59 AM:
> > On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
> >> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
> >>
> >> /Robert
> >
> > So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
> > That would lead me to more follow-up questions for the experts:
> > - what would happen if this battery was charged with only 15V?
> > - if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
> > https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
> > - I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?
> >
> > Thanks for any constructive replies.
> The voltage regulator might cause radio and other interference, adds complexity, and one more
> item to fail, possibly damaging the devices it was supposed to protect. There seems to be no
> sufficient reason to consider this chemistry, compared to LiFe batteries, unless you are space
> limited, due to higher cost and risk of over-voltage.
>
> Is battery space insufficient on your glider?
>
> --
> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> - "A Guide to Self-Launching Sailplane Operation"
> https://sites.google.com/site/motorgliders/publications/download-the-guide-1

Good points, Eric.
I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.

Uli
'AS'

[[email protected]]

If you charge it to 15V only you will have a total capacity low enough that it will not worth the money.
You can linearly low the output voltage with 3A/6A diode as it says on Peter millenaar page. There will be power dissipating on he diodes of course, but it's negligible. I do not recommend buck converters because if you don't study the switching frecuency the noise on the radio can be high.

My friend had the same low voltage issue on his lx 9070 and drove him to change the battery type.
If you treat them well you have a battery for 8 seasons.

> >
> > --
> > Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> > - "A Guide to Self-Launching Sailplane Operation"
> > https://sites.google.com/site/motorgliders/publications/download-the-guide-1
> Good points, Eric.
> I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
> My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.
>
> Uli
> 'AS'

[Moshe Braner]

On 11/26/2020 4:55 PM, AS wrote:
>
> Good points, Eric.
> I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
> My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.
>
> Uli
> 'AS'
>

Uli, the SN10b should not complain until the voltage is below 12V. The
LiFePO4 batteries should hold well above that for a long time, if fully
charged to start with (check your charger?). I don't know what else is
in your panel, but with only vario, volkslogger, radio, flarm and SN10
it seems rather unlikely that the pair of K2s are already mostly
discharged "early into the flight". If the low voltage is only while
transmitting, check whether there is too much resistance between the
battery and where theSN10b (reporting the low voltage) and the radio
supply lines diverge. Too much resistance due to thin wires, bad fuse
contact, bad switch, etc. For a test (on the ground) you can run an
extra wire from the battery directly to the radio and see if that
changes the behavior. Remember that electricity flows in closed loops,
i.e., the problem may be in the negative (ground) side of the wiring.

For comparison, I use one 12AH LFP battery, running vario, computer,
flarm and radio, and it would easily last for 2 or even 3 long flights
on one charge. Note: I do not have a transponder, those are relatively
power hungry.

[George Haeh]

I bought a CTEK LiFePO4 charger. Not cheap, but I'm getting 6 hours off a single K2 running Air Glide vario, PowerFlarm, radio, Trig 22 transponder and Oudie.

[Eric Greenwell[_4_]]

AS wrote on 11/26/2020 1:55 PM:
> On Thursday, November 26, 2020 at 1:02:00 PM UTC-5, Eric Greenwell wrote:
>> AS wrote on 11/26/2020 8:59 AM:
>>> On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
>>>> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
>>>>
>>>> /Robert
>>>
>>> So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
>>> That would lead me to more follow-up questions for the experts:
>>> - what would happen if this battery was charged with only 15V?
>>> - if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
>>> https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
>>> - I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?
>>>
>>> Thanks for any constructive replies.
>> The voltage regulator might cause radio and other interference, adds complexity, and one more
>> item to fail, possibly damaging the devices it was supposed to protect. There seems to be no
>> sufficient reason to consider this chemistry, compared to LiFe batteries, unless you are space
>> limited, due to higher cost and risk of over-voltage.
>>
>> Is battery space insufficient on your glider?
>>
>> --
>> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
>> - "A Guide to Self-Launching Sailplane Operation"
>> https://sites.google.com/site/motorgliders/publications/download-the-guide-1
>
> Good points, Eric.
> I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
> My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.

Is the battery voltage dropping when you key the radio? If not, or if it's a small amount, it
may be the wiring to the radio is too small or has connection issues, and it shares the wiring
with the SN!0B. The usual way to avoid this is to wire the SN10B "directly" to the battery and
to a good ground. The positive lead should have a fuse near the battery.


--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1

[AS]

On Thursday, November 26, 2020 at 11:32:32 PM UTC-5, Eric Greenwell wrote:
> AS wrote on 11/26/2020 1:55 PM:
> > On Thursday, November 26, 2020 at 1:02:00 PM UTC-5, Eric Greenwell wrote:
> >> AS wrote on 11/26/2020 8:59 AM:
> >>> On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
> >>>> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
> >>>>
> >>>> /Robert
> >>>
> >>> So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
> >>> That would lead me to more follow-up questions for the experts:
> >>> - what would happen if this battery was charged with only 15V?
> >>> - if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
> >>> https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
> >>> - I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?
> >>>
> >>> Thanks for any constructive replies.
> >> The voltage regulator might cause radio and other interference, adds complexity, and one more
> >> item to fail, possibly damaging the devices it was supposed to protect.. There seems to be no
> >> sufficient reason to consider this chemistry, compared to LiFe batteries, unless you are space
> >> limited, due to higher cost and risk of over-voltage.
> >>
> >> Is battery space insufficient on your glider?
> >>
> >> --
> >> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> >> - "A Guide to Self-Launching Sailplane Operation"
> >> https://sites.google.com/site/motorgliders/publications/download-the-guide-1
> >
> > Good points, Eric.
> > I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
> > My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.
> Is the battery voltage dropping when you key the radio? If not, or if it's a small amount, it
> may be the wiring to the radio is too small or has connection issues, and it shares the wiring
> with the SN!0B. The usual way to avoid this is to wire the SN10B "directly" to the battery and
> to a good ground. The positive lead should have a fuse near the battery.
> --
> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> - "A Guide to Self-Launching Sailplane Operation"
> https://sites.google.com/site/motorgliders/publications/download-the-guide-1

I guess it is time to rewire the panel. The mechanic of the previous owner left this rats nest of wires and that may be part of the problem.
Thanks for the constructive advise.

Uli
'AS'

[Jay Campbell]

On Friday, November 27, 2020 at 12:22:03 AM UTC-5, AS wrote:
> On Thursday, November 26, 2020 at 11:32:32 PM UTC-5, Eric Greenwell wrote:
> > AS wrote on 11/26/2020 1:55 PM:
> > > On Thursday, November 26, 2020 at 1:02:00 PM UTC-5, Eric Greenwell wrote:
> > >> AS wrote on 11/26/2020 8:59 AM:
> > >>> On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
> > >>>> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
> > >>>>
> > >>>> /Robert
> > >>>
> > >>> So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
> > >>> That would lead me to more follow-up questions for the experts:
> > >>> - what would happen if this battery was charged with only 15V?
> > >>> - if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
> > >>> https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
> > >>> - I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?
> > >>>
> > >>> Thanks for any constructive replies.
> > >> The voltage regulator might cause radio and other interference, adds complexity, and one more
> > >> item to fail, possibly damaging the devices it was supposed to protect. There seems to be no
> > >> sufficient reason to consider this chemistry, compared to LiFe batteries, unless you are space
> > >> limited, due to higher cost and risk of over-voltage.
> > >>
> > >> Is battery space insufficient on your glider?
> > >>
> > >> --
> > >> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> > >> - "A Guide to Self-Launching Sailplane Operation"
> > >> https://sites.google.com/site/motorgliders/publications/download-the-guide-1
> > >
> > > Good points, Eric.
> > > I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
> > > My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.
> > Is the battery voltage dropping when you key the radio? If not, or if it's a small amount, it
> > may be the wiring to the radio is too small or has connection issues, and it shares the wiring
> > with the SN!0B. The usual way to avoid this is to wire the SN10B "directly" to the battery and
> > to a good ground. The positive lead should have a fuse near the battery..
> > --
> > Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> > - "A Guide to Self-Launching Sailplane Operation"
> > https://sites.google.com/site/motorgliders/publications/download-the-guide-1
> I guess it is time to rewire the panel. The mechanic of the previous owner left this rats nest of wires and that may be part of the problem.
> Thanks for the constructive advise.
>
> Uli
> 'AS'
As to "rewire the rat's nest": I have never purchased a "new" glider, only a "used" one. In every case, there have been tubing and wiring issues and in each case I undertook to re-wire and re-tube everything I could get at. In every case, I have discovered something that was at least puzzling if not down-right scary. You don't have to be a wizard to discover problems and correct them. Just take it one thing at a time, get everything neat, and you will have a lot more fun come spring than if you don't.

[Mark Mocho]

I've rewired and/or replumbed my panel three or four times over the years as new equipment is added and old things are removed. Upgrading flight computers, displays, radios, transponders and the like have greatly enhanced the cockpit environment. One thing I have found invaluable is John DeRosa's series of helpful tips on glider maintenance. (http://aviation.derosaweb.net/presentations/) The "Aviation Electrical Best Practices" presentation shows the "right" way to go about wiring a cockpit. If you have any electrical skills, whether in industrial or home wiring, you will find the particular requirements for aviation are different. This guide steers you in the right direction. Thanks to "OHM" for these guides.

> As to "rewire the rat's nest": I have never purchased a "new" glider, only a "used" one. In every case, there have been tubing and wiring issues and in each case I undertook to re-wire and re-tube everything I could get at. In every case, I have discovered something that was at least puzzling if not down-right scary. You don't have to be a wizard to discover problems and correct them. Just take it one thing at a time, get everything neat, and you will have a lot more fun come spring than if you don't.

[AS]

On Friday, November 27, 2020 at 11:01:36 AM UTC-5, Mark Mocho wrote:
> I've rewired and/or replumbed my panel three or four times over the years as new equipment is added and old things are removed. Upgrading flight computers, displays, radios, transponders and the like have greatly enhanced the cockpit environment. One thing I have found invaluable is John DeRosa's series of helpful tips on glider maintenance. (http://aviation.derosaweb.net/presentations/) The "Aviation Electrical Best Practices" presentation shows the "right" way to go about wiring a cockpit. If you have any electrical skills, whether in industrial or home wiring, you will find the particular requirements for aviation are different. This guide steers you in the right direction. Thanks to "OHM" for these guides.
> > As to "rewire the rat's nest": I have never purchased a "new" glider, only a "used" one. In every case, there have been tubing and wiring issues and in each case I undertook to re-wire and re-tube everything I could get at. In every case, I have discovered something that was at least puzzling if not down-right scary. You don't have to be a wizard to discover problems and correct them. Just take it one thing at a time, get everything neat, and you will have a lot more fun come spring than if you don't.

Yes, I looked at 'OHM's' guides and will follow them. John deserves a medal for publishing this and his other 'How-to' guides.

Uli
'AS'

[John Sinclair[_5_]]

On Friday, November 27, 2020 at 11:39:43 AM UTC-8, AS wrote:
> On Friday, November 27, 2020 at 11:01:36 AM UTC-5, Mark Mocho wrote:
> > I've rewired and/or replumbed my panel three or four times over the years as new equipment is added and old things are removed. Upgrading flight computers, displays, radios, transponders and the like have greatly enhanced the cockpit environment. One thing I have found invaluable is John DeRosa's series of helpful tips on glider maintenance. (http://aviation.derosaweb.net/presentations/) The "Aviation Electrical Best Practices" presentation shows the "right" way to go about wiring a cockpit. If you have any electrical skills, whether in industrial or home wiring, you will find the particular requirements for aviation are different. This guide steers you in the right direction. Thanks to "OHM" for these guides.
> > > As to "rewire the rat's nest": I have never purchased a "new" glider, only a "used" one. In every case, there have been tubing and wiring issues and in each case I undertook to re-wire and re-tube everything I could get at. In every case, I have discovered something that was at least puzzling if not down-right scary. You don't have to be a wizard to discover problems and correct them. Just take it one thing at a time, get everything neat, and you will have a lot more fun come spring than if you don't.
> Yes, I looked at 'OHM's' guides and will follow them. John deserves a medal for publishing this and his other 'How-to' guides.
>
> Uli
> 'AS'

You can check for a bad component by looking for a voltage drop at each component, with mike button depressed........switches, fuses, plugs should have zero voltage drop. Don’t forget to check for voltage drop in the ground wire also. I once solved a problem like yours when I found everything was returning to the battery through a single 20 gage wire!
JJ


everything

[Dave Nadler]

On 11/26/2020 4:55 PM, AS wrote:
> ...I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N.

Uli - Follow the guidance given and track down the voltage drop!
Likely somewhere upstream of BOTH the radio and SN10.
Corroded connector, too thin wire, etc...

Caution: If you go over 15v, you will fry the SN10...

[kinsell]

On 11/26/20 2:55 PM, AS wrote:
> On Thursday, November 26, 2020 at 1:02:00 PM UTC-5, Eric Greenwell wrote:
>> AS wrote on 11/26/2020 8:59 AM:
>>> On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
>>>> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
>>>>
>>>> /Robert
>>>
>>> So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
>>> That would lead me to more follow-up questions for the experts:
>>> - what would happen if this battery was charged with only 15V?
>>> - if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
>>> https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
>>> - I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?
>>>
>>> Thanks for any constructive replies.
>> The voltage regulator might cause radio and other interference, adds complexity, and one more
>> item to fail, possibly damaging the devices it was supposed to protect. There seems to be no
>> sufficient reason to consider this chemistry, compared to LiFe batteries, unless you are space
>> limited, due to higher cost and risk of over-voltage.
>>
>> Is battery space insufficient on your glider?
>>
>> --
>> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
>> - "A Guide to Self-Launching Sailplane Operation"
>> https://sites.google.com/site/motorgliders/publications/download-the-guide-1
>
> Good points, Eric.
> I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
> My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.
>
> Uli
> 'AS'
>

I have some experience with that chemistry. It was in a large Goal Zero
'Yeti' power pack. They ran 12 volts directly from the battery, which I
tried to use with a DC/DC battery charger. The voltage regulation was
terrible, the battery charger shut off from low voltage with over 50%
state of charge remaining. Later, they started offering their own 12
volt DC/DC cable to take care of the problem. Should have been built
into the unit from the beginning.

As others have suggested, you really ought to look seriously at the
panel wiring. But also, you ought to do a battery test on the current
batteries, just because they're two years old doesn't mean anything.
Also, the voltage measuring built into instruments isn't always
accurate, make sure you have a real problem before proceeding.

[kinsell]

On 11/26/20 2:55 PM, AS wrote:
> On Thursday, November 26, 2020 at 1:02:00 PM UTC-5, Eric Greenwell wrote:
>> AS wrote on 11/26/2020 8:59 AM:
>>> On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
>>>> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
>>>>
>>>> /Robert
>>>
>>> So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
>>> That would lead me to more follow-up questions for the experts:
>>> - what would happen if this battery was charged with only 15V?
>>> - if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
>>> https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
>>> - I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?
>>>
>>> Thanks for any constructive replies.
>> The voltage regulator might cause radio and other interference, adds complexity, and one more
>> item to fail, possibly damaging the devices it was supposed to protect. There seems to be no
>> sufficient reason to consider this chemistry, compared to LiFe batteries, unless you are space
>> limited, due to higher cost and risk of over-voltage.
>>
>> Is battery space insufficient on your glider?
>>
>> --
>> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
>> - "A Guide to Self-Launching Sailplane Operation"
>> https://sites.google.com/site/motorgliders/publications/download-the-guide-1
>
> Good points, Eric.
> I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
> My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.
>
> Uli
> 'AS'
>


Just to pile on a little bit more, the type of battery you're looking at
is commonly called lithium-cobalt and isn't new at all. Someone at
Boeing thought it sounded really neat, and designed it into the 787.
After a few fires, they 'fixed' the problem by putting them in steel
containment boxes with blowout plugs to the atmosphere.

https://www.youtube.com/watch?v=rvkEpstd9os&t=280s

Switching to a battery like that in order to fix what is likely a wiring
issue isn't a good idea.

[2G]

On Saturday, November 28, 2020 at 4:07:14 PM UTC-8, kinsell wrote:
> On 11/26/20 2:55 PM, AS wrote:
> > On Thursday, November 26, 2020 at 1:02:00 PM UTC-5, Eric Greenwell wrote:
> >> AS wrote on 11/26/2020 8:59 AM:
> >>> On Thursday, November 26, 2020 at 11:19:57 AM UTC-5, wrote:
> >>>> I have used such a battery since July. Works just fine for me in my ASG 32 Mi with lots of electronic stuff.
> >>>>
> >>>> /Robert
> >>>
> >>> So there is already some operational experience with this type of batteries, which is good to hear. The warnings about the initially high voltage of 16+V is well taken. I checked the spec's of the stuff I have on and behind my panel and most of it is limited to only 15V.
> >>> That would lead me to more follow-up questions for the experts:
> >>> - what would happen if this battery was charged with only 15V?
> >>> - if the above is not advisable, would the use of an electronic voltage regulator like this one be an option?
> >>> https://vetco.net/products/dc-dc-adjustable-step-down-voltage-regulator-module-with-volt-meter-d92?gclid=Cj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EEnZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
> >>> - I am not familiar with this type of electronics but reading the specifications of it, I see a 'Ripple Frequency' of 150kHz on the output. Could that mess up the electronics?
> >>>
> >>> Thanks for any constructive replies.
> >> The voltage regulator might cause radio and other interference, adds complexity, and one more
> >> item to fail, possibly damaging the devices it was supposed to protect.. There seems to be no
> >> sufficient reason to consider this chemistry, compared to LiFe batteries, unless you are space
> >> limited, due to higher cost and risk of over-voltage.
> >>
> >> Is battery space insufficient on your glider?
> >>
> >> --
> >> Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
> >> - "A Guide to Self-Launching Sailplane Operation"
> >> https://sites.google.com/site/motorgliders/publications/download-the-guide-1
> >
> > Good points, Eric.
> > I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
> > My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.
> >
> > Uli
> > 'AS'
> >
> Just to pile on a little bit more, the type of battery you're looking at
> is commonly called lithium-cobalt and isn't new at all. Someone at
> Boeing thought it sounded really neat, and designed it into the 787.
> After a few fires, they 'fixed' the problem by putting them in steel
> containment boxes with blowout plugs to the atmosphere.
>
> https://www.youtube.com/watch?v=rvkEpstd9os&t=280s
>
> Switching to a battery like that in order to fix what is likely a wiring
> issue isn't a good idea.

The NMC chemistry is being used by most electric car manufacturers (except, notably, Tesla) as well as electric gliders. It does not have the stability of LFP chemistry, however. The reasons for this are discussed in detail in:
https://www.nature.com/articles/s41467-020-15355-0#Tab3
A friend of mine cancelled his order for a GP15 because, among other things, it can't be flown with a parachute (it uses a ballistic chute instead). He didn't like the prospect of the thing catching fire.
As others have said, you most likely have a wiring issue. Look at the voltage drop at each point in the wiring to the SN10b to find the culprit. I fly with a Bioenno LFP battery and have none of your issues. And I have a full glass panel with transponder and Flarm.

Tom

[Ian Molesworth]

At 16:59 26 November 2020, AS wrote:
>On Thursday, November 26, 2020 at 11:19:57 AM UTC-5,

>w=
>rote:
>> I have used such a battery since July. Works just fine for me in
my ASG
>3=
>2 Mi with lots of electronic stuff.=20
>>=20
>> /Robert
>
>So there is already some operational experience with this type of
>batteries=
>, which is good to hear. The warnings about the initially high
voltage of
>1=
>6+V is well taken. I checked the spec's of the stuff I have on and
behind
>m=
>y panel and most of it is limited to only 15V.=20
>That would lead me to more follow-up questions for the experts:
>- what would happen if this battery was charged with only 15V?
=20
>- if the above is not advisable, would the use of an electronic
voltage
>reg=
>ulator like this one be an option?
>https://vetco.net/products/dc-dc-adjustable-step-down-voltage-
regulator-mod=
>ule-with-volt-meter-d92?
gclid=3DCj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EE=
>nZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
>- I am not familiar with this type of electronics but reading the
>specifica=
>tions of it, I see a 'Ripple Frequency' of 150kHz on the output.
Could
>that=
> mess up the electronics?
>
>Thanks for any constructive replies.
>
>Uli
>'AS'
>
>

If you are going to put a 'power limiter' in the supply line then use
something linear not switching. Linear supplies dump extra power in
the form of heat. Switching power supplies make electrical noise
unless they are properly constructed and shielded ( ie expensive )
Knocking up a power regulator for this type of applicaion is barely
worth the effort.

One or even two simple diodes placed in series with the main
positive feed to those instruments rated at a lower maximum
voltage provides a safe and secure way to simply drop the voltage
into that device. As a side effect, you get additional reverse polarity
protection to your instruments!

for most instruments, a 1N4007 1 Amp diode would suffice. it drops
about 0.7v at very small currents and 1v at its maximum rating of 1
Amp.

A glass screen device might need a diode rated a little higher at say
2 or 3 Amps.

It might just be simpler to put a big diode rated at 20 amps or so in
line with the battery. A STTH20R04 will easily handle that sort of
current and give you an overall 0.6v minimum drop up to 1.5 drop
at 20 Amps.

These things are pennies even in single quantities.

[Dave Nadler]

On 11/28/2020 11:29 PM, Ian Molesworth wrote:

Seru=iously? SERIOUSLY??

> If you are going to put a 'power limiter'

It's a VOLTAGE limiter, not a POWER limiter.

> in the supply line then use
> something linear not switching. Linear supplies dump extra power in
> the form of heat. Switching power supplies make electrical noise
> unless they are properly constructed and shielded ( ie expensive )
> Knocking up a power regulator for this type of applicaion is barely
> worth the effort.

Its not worth the effort as HE SHOULD USE AN APPROPRIATE BATTERY.
A PROPERLY DESIGNED switcher DOES NOT need to radiate noise!
A switcher designed by a moron, well that's another story...

> One or even two simple diodes placed in series with the main
> positive feed to those instruments rated at a lower maximum
> voltage provides a safe and secure way to simply drop the voltage
> into that device. As a side effect, you get additional reverse polarity
> protection to your instruments!

Gee, I've recently documented a couple FIRES started that way!
Diodes DISSIPATE HEAT and WASTE ENERGY.
If they are not properly heat-sunk, YOU GET A FIRE.
Please do not try this at home.

YIKES.
Even for RAS...

[Jay Campbell]

On Friday, November 27, 2020 at 11:01:36 AM UTC-5, Mark Mocho wrote:
> I've rewired and/or replumbed my panel three or four times over the years as new equipment is added and old things are removed. Upgrading flight computers, displays, radios, transponders and the like have greatly enhanced the cockpit environment. One thing I have found invaluable is John DeRosa's series of helpful tips on glider maintenance. (http://aviation.derosaweb.net/presentations/) The "Aviation Electrical Best Practices" presentation shows the "right" way to go about wiring a cockpit. If you have any electrical skills, whether in industrial or home wiring, you will find the particular requirements for aviation are different. This guide steers you in the right direction. Thanks to "OHM" for these guides.
> > As to "rewire the rat's nest": I have never purchased a "new" glider, only a "used" one. In every case, there have been tubing and wiring issues and in each case I undertook to re-wire and re-tube everything I could get at. In every case, I have discovered something that was at least puzzling if not down-right scary. You don't have to be a wizard to discover problems and correct them. Just take it one thing at a time, get everything neat, and you will have a lot more fun come spring than if you don't.

Yes, I have been using his advice for a while now. Good stuff. I have 9 AH LA batteries and have always tested them this time of year by putting a 10 ohm 25 watt resistor across the output and taken voltage readings each hour down to 9 VDC or so. If the battery doesn't go 4-5 hours, I replace it. So how does one "check" a LiPo? Anyone done it?

As a side note, I was informed in the owner's literature never to put two of their LiPo's in parallel, as you can with the LA type. Read the manual if you have any parallel circuits in your ship before deploying in this manner.

[Martin Gregorie[_6_]]

On Wed, 02 Dec 2020 22:19:51 -0800, Jay Campbell wrote:

> On Friday, November 27, 2020 at 11:01:36 AM UTC-5, Mark Mocho wrote:
>> I've rewired and/or replumbed my panel three or four times over the
>> years as new equipment is added and old things are removed. Upgrading
>> flight computers, displays, radios, transponders and the like have
>> greatly enhanced the cockpit environment. One thing I have found
>> invaluable is John DeRosa's series of helpful tips on glider
>> maintenance. (http://aviation.derosaweb.net/presentations/) The
>> "Aviation Electrical Best Practices" presentation shows the "right" way
>> to go about wiring a cockpit. If you have any electrical skills,
>> whether in industrial or home wiring, you will find the particular
>> requirements for aviation are different. This guide steers you in the
>> right direction. Thanks to "OHM" for these guides.
>> > As to "rewire the rat's nest": I have never purchased a "new" glider,
>> > only a "used" one. In every case, there have been tubing and wiring
>> > issues and in each case I undertook to re-wire and re-tube everything
>> > I could get at. In every case, I have discovered something that was
>> > at least puzzling if not down-right scary. You don't have to be a
>> > wizard to discover problems and correct them. Just take it one thing
>> > at a time, get everything neat, and you will have a lot more fun come
>> > spring than if you don't.
>
> Yes, I have been using his advice for a while now. Good stuff. I have
> 9 AH LA batteries and have always tested them this time of year by
> putting a 10 ohm 25 watt resistor across the output and taken voltage
> readings each hour down to 9 VDC or so. If the battery doesn't go 4-5
> hours, I replace it. So how does one "check" a LiPo? Anyone done it?
>
> As a side note, I was informed in the owner's literature never to put
> two of their LiPo's in parallel, as you can with the LA type. Read the
> manual if you have any parallel circuits in your ship before deploying
> in this manner.

I use an old Pro-Peak Prodigy II to cycle and measure my battery capacity
each year. I sling 7.2AH SLAs once they drop below 5 Ah capacity but of
course ymmv.

The Pro-Peak Prodigy II handles multiple battery chemistries (SLA, NiCd,
NiMH, LiPo) and can discharge and recharge any of them. Check out your
local RC model shop or website and you'll find similar systems for
reasonable prices. Mine self-limits to 400mA discharge and charges at a
similar rate and can be run off a battery or a mains adapter: the
electric RC guys take their chargers to the flying field and charge
models from their car battery.



--
--
Martin | martin at
Gregorie | gregorie dot org

[Moshe Braner]

On 12/3/2020 8:31 AM, Martin Gregorie wrote:
> On Wed, 02 Dec 2020 22:19:51 -0800, Jay Campbell wrote:
>
>> On Friday, November 27, 2020 at 11:01:36 AM UTC-5, Mark Mocho wrote:
>>> I've rewired and/or replumbed my panel three or four times over the
>>> years as new equipment is added and old things are removed. Upgrading
>>> flight computers, displays, radios, transponders and the like have
>>> greatly enhanced the cockpit environment. One thing I have found
>>> invaluable is John DeRosa's series of helpful tips on glider
>>> maintenance. (http://aviation.derosaweb.net/presentations/) The
>>> "Aviation Electrical Best Practices" presentation shows the "right" way
>>> to go about wiring a cockpit. If you have any electrical skills,
>>> whether in industrial or home wiring, you will find the particular
>>> requirements for aviation are different. This guide steers you in the
>>> right direction. Thanks to "OHM" for these guides.
>>>> As to "rewire the rat's nest": I have never purchased a "new" glider,
>>>> only a "used" one. In every case, there have been tubing and wiring
>>>> issues and in each case I undertook to re-wire and re-tube everything
>>>> I could get at. In every case, I have discovered something that was
>>>> at least puzzling if not down-right scary. You don't have to be a
>>>> wizard to discover problems and correct them. Just take it one thing
>>>> at a time, get everything neat, and you will have a lot more fun come
>>>> spring than if you don't.
>>
>> Yes, I have been using his advice for a while now. Good stuff. I have
>> 9 AH LA batteries and have always tested them this time of year by
>> putting a 10 ohm 25 watt resistor across the output and taken voltage
>> readings each hour down to 9 VDC or so. If the battery doesn't go 4-5
>> hours, I replace it. So how does one "check" a LiPo? Anyone done it?
>>
>> As a side note, I was informed in the owner's literature never to put
>> two of their LiPo's in parallel, as you can with the LA type. Read the
>> manual if you have any parallel circuits in your ship before deploying
>> in this manner.
>
> I use an old Pro-Peak Prodigy II to cycle and measure my battery capacity
> each year. I sling 7.2AH SLAs once they drop below 5 Ah capacity but of
> course ymmv.
>
> The Pro-Peak Prodigy II handles multiple battery chemistries (SLA, NiCd,
> NiMH, LiPo) and can discharge and recharge any of them. Check out your
> local RC model shop or website and you'll find similar systems for
> reasonable prices. Mine self-limits to 400mA discharge and charges at a
> similar rate and can be run off a battery or a mains adapter: the
> electric RC guys take their chargers to the flying field and charge
> models from their car battery.
>

I followed others' recommendations and use the iMax B6
charger/discharger. Capable and cheap. But a test with a suitable
resistor, voltmeter and clock is also fine. I wouldn't discharge a
lead-acid battery down to 9V, that is damaging to its longevity. I'd
stop at 10.5V or 11V. Do that when the battery is new and you'll have a
baseline to compare to when the battery is older. For a lithium battery
you can do a similar test, just expect that the voltage will decline
much more gradually for most of the discharge, and then fall rapidly as
the battery nears exhaustion. There is very little additional capacity
below 11.5V or so. The built-in protection circuit may shut it down
between measurements if the voltage falls far enough. That's OK. Just
recharge it to turn it back on.

[Eric Greenwell[_4_]]

Jay Campbell wrote on 12/2/2020 10:19 PM:
> On Friday, November 27, 2020 at 11:01:36 AM UTC-5, Mark Mocho wrote:
>> I've rewired and/or replumbed my panel three or four times over the years as new equipment is added and old things are removed. Upgrading flight computers, displays, radios, transponders and the like have greatly enhanced the cockpit environment. One thing I have found invaluable is John DeRosa's series of helpful tips on glider maintenance. (http://aviation.derosaweb.net/presentations/) The "Aviation Electrical Best Practices" presentation shows the "right" way to go about wiring a cockpit. If you have any electrical skills, whether in industrial or home wiring, you will find the particular requirements for aviation are different. This guide steers you in the right direction. Thanks to "OHM" for these guides.
>>> As to "rewire the rat's nest": I have never purchased a "new" glider, only a "used" one. In every case, there have been tubing and wiring issues and in each case I undertook to re-wire and re-tube everything I could get at. In every case, I have discovered something that was at least puzzling if not down-right scary. You don't have to be a wizard to discover problems and correct them. Just take it one thing at a time, get everything neat, and you will have a lot more fun come spring than if you don't.
>
> Yes, I have been using his advice for a while now. Good stuff. I have 9 AH LA batteries and have always tested them this time of year by putting a 10 ohm 25 watt resistor across the output and taken voltage readings each hour down to 9 VDC or so. If the battery doesn't go 4-5 hours, I replace it. So how does one "check" a LiPo? Anyone done it?
>
> As a side note, I was informed in the owner's literature never to put two of their LiPo's in parallel, as you can with the LA type. Read the manual if you have any parallel circuits in your ship before deploying in this manner.
>
SLA battery capacity at low to moderate currents (like you are doing) is usually measured down
to 11.0 volts for a "100% discharge". Going lower than that causes unnecessary damage that
shortens the life of the batter.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1

[2G]

On Saturday, November 28, 2020 at 8:30:05 PM UTC-8, Ian Molesworth wrote:
> At 16:59 26 November 2020, AS wrote:
> >On Thursday, November 26, 2020 at 11:19:57 AM UTC-5,
>
> >w=
> >rote:
> >> I have used such a battery since July. Works just fine for me in
> my ASG
> >3=
> >2 Mi with lots of electronic stuff.=20
> >>=20
> >> /Robert
> >
> >So there is already some operational experience with this type of
> >batteries=
> >, which is good to hear. The warnings about the initially high
> voltage of
> >1=
> >6+V is well taken. I checked the spec's of the stuff I have on and
> behind
> >m=
> >y panel and most of it is limited to only 15V.=20
> >That would lead me to more follow-up questions for the experts:
> >- what would happen if this battery was charged with only 15V?
> =20
> >- if the above is not advisable, would the use of an electronic
> voltage
> >reg=
> >ulator like this one be an option?
> >https://vetco.net/products/dc-dc-adjustable-step-down-voltage-
> regulator-mod=
> >ule-with-volt-meter-d92?
> gclid=3DCj0KCQiAwf39BRCCARIsALXWETz1ec6W-C6QcqB57EE=
> >nZ5_ejcqc_VjaXarrYW8J-9hJiGyYLnUmczkaAnEdEALw_wcB
> >- I am not familiar with this type of electronics but reading the
> >specifica=
> >tions of it, I see a 'Ripple Frequency' of 150kHz on the output.
> Could
> >that=
> > mess up the electronics?
> >
> >Thanks for any constructive replies.
> >
> >Uli
> >'AS'
> >
> >
> If you are going to put a 'power limiter' in the supply line then use
> something linear not switching. Linear supplies dump extra power in
> the form of heat. Switching power supplies make electrical noise
> unless they are properly constructed and shielded ( ie expensive )
> Knocking up a power regulator for this type of applicaion is barely
> worth the effort.
>
> One or even two simple diodes placed in series with the main
> positive feed to those instruments rated at a lower maximum
> voltage provides a safe and secure way to simply drop the voltage
> into that device. As a side effect, you get additional reverse polarity
> protection to your instruments!
>
> for most instruments, a 1N4007 1 Amp diode would suffice. it drops
> about 0.7v at very small currents and 1v at its maximum rating of 1
> Amp.
>
> A glass screen device might need a diode rated a little higher at say
> 2 or 3 Amps.
>
> It might just be simpler to put a big diode rated at 20 amps or so in
> line with the battery. A STTH20R04 will easily handle that sort of
> current and give you an overall 0.6v minimum drop up to 1.5 drop
> at 20 Amps.
>
> These things are pennies even in single quantities.

Any passive device that drops voltage will be inefficient and do it by converting the power into heat. Low noise switching regulators do not need to be expensive. Here is but one example:
https://www.analog.com/en/products/power-management/switching-regulators/ultralow-noise-regulators.html#
https://www.analog.com/en/parametricsearch/11001#/d=5351|5573|5574|5349|5358|5345|5575|5362|5589|s3| s5
These devices also provide current limiting as a bonus

Tom