OAT on LX-7000

[C-FFKQ (42)]

Probably a dumb question... and I think I know the answer... but...
May I cut the OAT wires and insert a two-pin connector so that I may place the OAT sensor in a good location in my ship and still easily remove the panel?
Looking at the schematics, it's just 2 wires leading to the sensor, so I would think it's okay, but my knowledge of electronics is rather limited (and I'm rather ham-fisted).

TIA,
John

[Paul Remde]

Hi John,

If I remember my engineering courses correctly, cutting and reconnecting the
leads of a temperature probe is not recommended. The temperature sensing
depends on the slight difference in the metals in the 2 wires and cutting
and especially soldering them together again, or connecting them with metal
connectors will change how well they work and will give them an offset. I
imagine the LX7000 was calibrated to the sensor at the factory. It would
need to be recalibrated if you cut it and solder it together or use
connectors.

That said, at least one soaring instrument manufacturer is convinced that
the temperature sensor is not necessary. They are often installed in
locations that lead to very inaccurate readings - such as in the air vent.
Those inaccuracies lead to worse information then you would get without a
temperature sensor at all.

Best Regards,

Paul Remde
__________________________

"C-FFKQ (42)" wrote in message
...

Probably a dumb question... and I think I know the answer... but...
May I cut the OAT wires and insert a two-pin connector so that I may place
the OAT sensor in a good location in my ship and still easily remove the
panel?
Looking at the schematics, it's just 2 wires leading to the sensor, so I
would think it's okay, but my knowledge of electronics is rather limited
(and I'm rather ham-fisted).

TIA,
John

[Eric Greenwell[_4_]]

It's very unlikely any instrument is using thermocouples for temperature
sensing; instead, they use standard devices that connect with plain old
wire.

So, cut the cable, put in the connector, and you are good to go. Be sure
the each sensor wire is connected to the same wire from the instrument
it was connected to previously.


On 5/7/2013 5:44 AM, Paul Remde wrote:
> Hi John,
>
> If I remember my engineering courses correctly, cutting and reconnecting
> the leads of a temperature probe is not recommended. The temperature
> sensing depends on the slight difference in the metals in the 2 wires
> and cutting and especially soldering them together again, or connecting
> them with metal connectors will change how well they work and will give
> them an offset. I imagine the LX7000 was calibrated to the sensor at
> the factory. It would need to be recalibrated if you cut it and solder
> it together or use connectors.
>
> That said, at least one soaring instrument manufacturer is convinced
> that the temperature sensor is not necessary. They are often installed
> in locations that lead to very inaccurate readings - such as in the air
> vent. Those inaccuracies lead to worse information then you would get
> without a temperature sensor at all.
>
> Best Regards,
>
> Paul Remde
> __________________________
>
> "C-FFKQ (42)" wrote in message
> ...
>
> Probably a dumb question... and I think I know the answer... but...
> May I cut the OAT wires and insert a two-pin connector so that I may
> place the OAT sensor in a good location in my ship and still easily
> remove the panel?
> Looking at the schematics, it's just 2 wires leading to the sensor, so I
> would think it's okay, but my knowledge of electronics is rather limited
> (and I'm rather ham-fisted).
>
> TIA,
> John


--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
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