EE help please - - locating Schottky diode

Want to install Schottky diode Mouser part# 844-95SQ015 http://www.mouser.com/ds/2/427/95sq015-27345.pdf in all 3 of my battery supply lines.

Setup is spar-shelf batteries "+" side through 5 amp flat auto fuse Anderson PowerPole connectors + and - wire under seat-pan all 3 "+" through panel mounted on/off switch positive terminal block with entire input side "jumped". All 3 "-" battery leads go to negative terminal block with entire input side "jumped".

Where is the proper place to locate the diodes? Which way will the diode ring orientate?

On the negative terminal block, should there also be a ground wire run to the elevator/aileron yoke?

Thanks.

Ben

Are you saying you want to add a diode for each battery so that in an unbalanced situation(batteries not all at the same potential), you dont end up draining the one that is most full for the other 2?

Correct. Cheap insurance.

On Monday, April 29, 2013 4:13:46 PM UTC-4, wrote:
Are you saying you want to add a diode for each battery so that in an unbalanced situation(batteries not all at the same potential), you dont end up draining the one that is most full for the other 2?

On Apr 29, 1:00*pm, wrote:
Where is the proper place to locate the diodes? Which way will the diode ring orientate?

Not sure if there is a "proper" place for the diodes, but here is what
I would do.
First, route all "+" wires to the terminal block (say, terminals 1, 2,
and 3). Crimp ring lugs onto the diode leads. Connect the first diode
between terminals 1 and 4, second one between 2 and 4 and the third
one between 3 and 4. The ring on each diode case should point toward
terminal 4. Then connect terminal 4 to your on/off switch.

This, of course, assumes that you have spare terminals. Your
description suggests that you do.

Should you choose to put the diodes in line with the + wires instead,
do NOT put them anywhere where their leads would be subject to
bending. For example, right at the battery would be a *bad* place.
Behind the panel, with strain relief on both sides, would probably be
OK.

Bart

On the positive wire (probably red) from the battery, cut the wire. the ringed end should be on the end that goes on to the airplane. The Non-Ringed end should be connected to the cut end that leads back to the battery.

Important. do this splice in the wires that stay with the airplane not in the ones that stay with the battery. Otherwise you will wont be able to charge your batteries. Also if you have a way to charge the batteries in the plane (for example a solar panel,) you will need to connect these diodes between the charger and the airplane. (not between the charger and the battery.

Thanks Bart and te...understood. Out of curiosity, what is the proper way to strain relief a diode?

All good information. Great comment about not putting the diode on
the battery or it can't charge. Looks like you picked a good sized
diode (9 amps).

I'll add one highlight about the orientation of the battery which was
kind of buried within the answers above. A diode's symbol looks like
an arrow with a vertical line at the point.

I hope this "text-ture" comes through if your news reader uses a mono-
spaced font.

| /|
| / |
Cathode ----| |---- Anode
To Equip | \ | To Battery (+) terminal
| \|

This arrow "points" along the current flow. The vertical line
(cathode) is represented by the painted ring on the diode.

The current flow is from positive (+) to negative (-). That is, from
the positive terminal of the battery, through and in the direction of
the diode's "arrow", through the equipment and back to the negative
terminal of the battery (or ground). Physicists might disagree with
this description of current flow but EE's won't. Again, the arrow and
line should "point" away from the battery (+) terminal and towards the
equipment.

It is pretty simple because if you don't do it right, nothing will
work! Test with a voltmeter. If nada volts, then just turn the diode
around! So you won't be surprised, remember that you will "loose"
1/4V (Vf = 0.25v)across the diode.

My $0.02. Good luck.

- John

PS - Glad you are using Powerpoles. Great stuff that!
PPS - Full disclosure - I don't use diodes. ;-)

Hello JohnDeRosa:

Using three batteries, I have three "-" battery wires running to a negative terminal strip all "jumped on the terminal input side. Is it also best to ground the "-" terminal strip to the largest metal mass in the glider such as the elevator/aileron yoke?

Thanks all.

Ben

On Monday, April 29, 2013 5:36:46 PM UTC-4, JohnDeRosa wrote:
All good information. Great comment about not putting the diode on

the battery or it can't charge. Looks like you picked a good sized

diode (9 amps).

On Apr 29, 2:34*pm, wrote:
Thanks Bart and te...understood. Out of curiosity, what is the proper way to strain relief a diode?

I have used zip ties for this purpose. Here's an example:
https://picasaweb.google.com/lh/phot...t=d irectlink

In your case, you could connect the three diodes together at your on/
off switch, solder the + wires to each diode and the zip tie each wire
to a convenient anchor. You may want to put heat shrink on the solder
joints, but leave the diode cases exposed.

If you use self-adhesive zip tie anchors like I did, do not count on
the adhesive lasting long. It's much better to remove all the adhesive
and just use CA glue.

Bart

Thanks Bart...I'm using three independent battery on/off switches without a master switch. Think I'm good to go with the diodes.