Electric gauge senders

[Grand_Wag_85]

I'm installing a digital automotive water temp gauge to read the operating temp of an outdoor furnace. The sender probe will be 50-100FT away from the gauge.

My main concern is inaccuracy due to the long run of wire. You guys think it will register high or low? Once I get it figured out and determine what the difference in resistance is at the sender and gauge what do I wire in to compensate accordingly?

Thanks!

[BGW]

Depends on which way it's designed. On most, the added resistance will make it read cold, but on some, it will make it read high. You can't compensate by wiring in a resistor, the best you can do is use heavy gauge wire for the run and make very clean connections.

[Grand_Wag_85]

Looks like it's definitely off a bit I did use heavy gauge wire. At the ambient outdoor air temp (75*F) the gauge read 74 whereas the actual water temp was 75*F. Fired it up and it reads 10*F low at max temp.