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Technical => Electronics & Car Audio Forum => Topic started by: s3racing on August 13, 2015, 07:51:33 AM

Title: Switching between two senders for one gauge
Post by: s3racing on August 13, 2015, 07:51:33 AM
Has any one tried doing this before? Using one gauge for two senders. I want to have two temp and two pressure senders each pair wired to one gauge over a switch. So that I can switch between before cooler signal and after cooler signal. Could that work or would I have accuracy problems because they are resistance based signals?? Any ideas

Thanks for any pointers or help

René
Title: Re: Switching between two senders for one gauge
Post by: jim martin on August 13, 2015, 07:59:16 AM
did it with a autometer head temp gauge the switch i used had very little resistance and made no visable difference on reading .
all you can do is try it
Title: Re: Switching between two senders for one gauge
Post by: s3racing on August 13, 2015, 10:47:04 AM
Thanks Jim
I guess I'm just going to have to give it a go. I don't want whole dad covered in gauges but also want to check the effectiveness of my cooler and the pressure changes etc. thanks
Title: Re: Switching between two senders for one gauge
Post by: owdlvr on August 13, 2015, 02:39:56 PM
(https://airspeedparts.com/forums/proxy.php?request=http%3A%2F%2Ffarm8.staticflickr.com%2F7432%2F12671286935_9aff23e2f2_z.jpg&hash=af54fbd9ae419e4514389ed18ed6103bf6887ddc)

Oil temp gauge in the rally bug is actually reading three different senders. The rotary switch to the right of the gauge controls whether I'm reading of the 'E'ngine, 'T'ank, or 'F'eed (post oil cooler) sensor. The wiring for this is relatively simple, and could easily be done with a pressure gauge with no trouble. You will need to test each of the senders to correlate their accuracy both to the temp/pres you're measuring and to each other. My three oil temp senders, for instance, are off by a total of 10deg from each other when measured in boiling water. Once i figured that out, it explained why the temps "in-car" weren't matching up to what I expected.

-Dave
Title: Re: Switching between two senders for one gauge
Post by: s3racing on August 13, 2015, 09:23:34 PM
Thanks Dave that will definitively help to keep the dash clutter to a minimum. :-)

Rene