VanDweller Community Forums

Full Version: Inexpensive amp hour counter
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
A Trimetric or Victron battery monitor runs about 220$ and that is usually without the required shunt

The following link is about 36$ and is a very basic/bare bones version of a Trimetric or Victron.

I post the 500 amp version for those that want to monitor alternator current.  While the alternator could never create this much current, the starter could possibly draw that much current, and for the unit to monitor alternator current, the shunt must be wired in between the batteries and vehicle grounds and will thus pass starter current too.

 http://www.ebay.com/itm/DC-120V-500A-Volt-Amp-Combo-Meter-Battery-Charge-Discharge-Indicator-Camper-CAR-/170901504188?pt=LH_DefaultDomain_0&hash=item27ca8600bc.

If one is( foolishly) not using the alternator to recharge, then the 200 amp version can be utilized and is also a smidge cheaper too:

http://www.ebay.com/itm/DC-120V-200A-Volt-Amp-Combo-Meter-Battery-Charge-Discharge-Indicator-With-Shunt-/170901497030?pt=LH_DefaultDomain_0&hash=item27ca85e4c6

I've no idea how well these are made, nor how accurate they are.  
I post because many want a Trimetric or similar but then balk at their price.

Well China to the rescue, again, with all that wonderful quality control one comes to expect from low$ items

Wiring of the shunt is confusing to many.  Basically there is a Load/source side of the shunt and a battery side of the Shunt. All grounds go to the load side of the shunt.  From the battery side of the shunt, only one cable goes from Shunt to battery (-) post.  No other cable can goto battery (-), or the current carried by that wire will not be measured or counted.

Even a well programmed trimetric is only ~90% accurate as to actual battery state of charge.
I've requested a user manual from them. Will post info if I get a hold of it. 
Bought one just to see how well they work.
I was almost tempted to buy one for the same reason.

But I already have a battery monitor. And, they are enlightening tools.

I like seeing the Amp hour from full screen, and comparing that to battery voltage, and the load the battery is under at that time.

One can see a battery age, and when it needs an EQ cycle, and estimate how much more life to expect from the battery.

I'll be searching for a new battery in about 100 to 150 more deep cycles. I'll see if I can acquire a Trojan group 31.
(01-29-2015, 12:53 AM)SternWake Wrote: [ -> ]I was almost tempted to buy one for the same reason.

But I already have a battery monitor.  And, they are enlightening tools.

I like seeing the Amp hour from full screen, and comparing that to battery voltage, and the load the battery is under at that time.

One can see a battery age, and when it needs an EQ cycle, and estimate how much more life to expect from the battery.

I'll be searching for a new battery in about 100 to 150 more deep cycles.  I'll see if I can acquire a Trojan group 31.

It appears about 5 or 6 more posts after this one have been deleted.  

Is there any particular reason?
(01-29-2015, 10:51 PM)SternWake Wrote: [ -> ]It appears about 5 or 6 more posts after this one have been deleted.  

Is there any particular reason?

We lost that in the crash that happened today.
I know there was a forum crash earlier and posts were lost. maybe that's why. btw thanks for the link stern. highdesertranger
Repost, I put up the user manual earlier. Here it is again.

[attachment=2524]
We have automatic backups so when we recovered from the crash we reverted to the last back up so about 2-4 hours of posts were lost.
Bob
Ahh, was not aware of the crash.