Hall effect sensor

Per Dynon, all positions for a shunt or Hall effect sensor have the wire between the batter and the starter not pass through the devices. (See page 7-62 of the guide)

I understand that during start, the Amps are very high.

The GRT CS-01 says it is good for +/- 100 amps. I'm guessing that during start, we are up to 2-3 times than amount. Obviously, a shunt would not like that. But in the case of a Hall effect sensor, using induction, that would translate into a higher voltage level. But given that it outputs millivolts, it seems it wouldn't be very high. Is it really incapable of handling that? Or is that just what it is scaled for, so when the current is higher, it would only read 100 amps?

I would be hooking it to a Dynon Skyview EMS. Due to the wire routing in my plane, I can only use position "A" in this way. My other alternative is to use Position "B", and given I have a VP-X, I still get the battery values, but that puts the sensor in the engine bay, and makes the install less clean.

Am I being foolish for considering this? I really want to know, and not guess, because I would hate to mess up the EMS during my first start.

Main buss feed line.

If you don't want to pick-up the 2-300 or so Amps from starter load, you can put your pick-up of ether type on the "B" lead or main feed line going to your main buss and take your readings there for your load values of your system. Most of the EFIS let you pickup system voltage by just hooking up to it anywhere. That will tell you if you have charging voltage or not. This is what we do and only check the starter draw if we think we have a bad starter. If your Alt. is making the correct Voltage while under load you will know if it is charging.
Just how we handle this systems lay-out. Yours, R.E.A. III #80888

Great news

This is actually great news for me. I was hoping the output would not go over the 5 volts. It's not that I want to measure starter amperage, it is that there is no place for me to put it, without the starter current being in line while keeping the sensor out of the engine bay. Based on how the two of you responded, it will do exactly what I hoped for. Thanks!

Chuck,

What you may want to do is use a lower amp sensor. If you are interested in the amps into or out of the battery, once it is recharged, that number is pretty small on the order of 5 or so. Using a 100 amp sensor means you are looking for differences of just a percent or so.

I previously had a sensor on the big lead to the starter and had the bus distribute from there. I recently changed to a 10 amp sensor and have just the bus feed thru it. I think it gives more meaningful information.

Jim Butcher

Power hog

Unfortunately, she is a power hog, and will regularly draw more than 10 amps.