Max number of sensors on TPS 5v ref

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DHH
Helpful MS/Extra'er
Posts: 76
Joined: Mon Feb 27, 2017 12:19 am

Max number of sensors on TPS 5v ref

Post by DHH »

I know this has been asked before, but I can't seem to find it.

I have 6 sensors that need 5v reference. Can I tie them all to the TPS 5v reference or should I run another wire to the proto 5v?

I have the following sensors that need a 5v ref:
TPS, Cam, Crank, Oil pressure, Fuel pressure, External MAP
6.2L LS3, Procharged, MS3X V3.0
22' Donzi Classic
Not yet running...
http://www.donzi.net/forums/showthread. ... 502-to-LS3 (Disclaimer: Contains naive info :D )
billr
Super MS/Extra'er
Posts: 6828
Joined: Sun May 15, 2011 11:41 am
Location: Walnut Creek, Calif. USA

Re: Max number of sensors on TPS 5v ref

Post by billr »

Should be no problem, connect them all to that 5V ref pin.
DHH
Helpful MS/Extra'er
Posts: 76
Joined: Mon Feb 27, 2017 12:19 am

Re: Max number of sensors on TPS 5v ref

Post by DHH »

Thanks. I know the draw per sensor is minute. Just wasn't sure if the cumulative amount was too high.
6.2L LS3, Procharged, MS3X V3.0
22' Donzi Classic
Not yet running...
http://www.donzi.net/forums/showthread. ... 502-to-LS3 (Disclaimer: Contains naive info :D )
billr
Super MS/Extra'er
Posts: 6828
Joined: Sun May 15, 2011 11:41 am
Location: Walnut Creek, Calif. USA

Re: Max number of sensors on TPS 5v ref

Post by billr »

Note that there are two considerations in you first post.

First, how much the 5V regulator can supply, and I believe that is 500 mA. If you figure to reserve 100 mA for the MS circuits and basic sensors (MAP, TPS, CLT, and MAT) that still leaves 400 mA for extra sensors. Figuring maybe as much as 20 mA for each extra sensors, that's 20 more sensors.

Second, is how much current the one TPS 5V pin can handle. That is still plenty, well over 1A, and running a separate wire back to the proto area would only relieve loading at that pin; it would still be drawing from the same 5V regulator. Got it? Running a separate wire back to the proto area gains you nothing.
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