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Old 07-18-2011, 07:12 AM   #11
Bill
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Originally Posted by brulaz View Post
Has anybody seen a mod that constantly monitors the trailer brake current? Perhaps a very low resistance shunt in series and small voltage drop readout?
For most people, that is exactly the way to do it. For about $5 including shipping, you can buy on eBay a small digital voltmeter panel that measures 0-200 mV. For this voltage range, the readout can be set to read 0-to-2, 0-to-20, or 0-to-200. You would choose 0-to-20, to represent 0-to-20 amps. For 20 amps to produce 200 mV, you need a shunt of 0.01 ohm (10 milli-ohm) resistance, also easily available.

A pair of Dexter electric brakes will draw a maximum of 6 amps. With 6 amps through it, the shunt will produce 60 mV, and the voltmeter panel will read "6", meaning 6 amps. Just what you want. And the 60 mV of drop in the brake voltage is insignificant.

Have I done the math right?

I have intended to do this for years, but kept hoping that Tekonsha would respond. No such luck.

Bill
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