how do you monitor trailer battery voltage?

I used the Trimetric 2025 battery monitor. Costly $$$$, but more information than I could possible use. I installed this when i put my solar on to monitor how well it was working.

johnm1 wrote:
I really like that setup, what is it and where did you get it? In other words more info ... please and thank you.

It is from Martel Meters, quick mount series. You may find a lower cost solution on ebay.

http://www.martelmeters.com/products.php?cat=1

data sheet

smkettner wrote:

I really like that setup, what is it and where did you get it? In other words more info ... please and thank you.

Just inside the entrance door, I put in a 12v outlet with a plug in DC voltmeter. Under that is a 120v outlet with an AC voltmeter, then an indoor/outdoor thermometer, the thermostat and the tank/battery monitor. Everything can be checked at a glance. The only thing missing is the solar charge controller which I'll move at some point.

shawnzy wrote:
I had the battery run out from putting the slide out 3 times other day

Three times?

I installed my three meter DC MONITORING PANEL when we first got into taking the OFF-ROAD POPUP camper off the power grid. It is very important to us to monitor the batteries.

My three panel meter group consists of two digital DC VOLTMETERs which is direct connected right at my battery bank source and one digital +/- 75AMP DC Current meter which measures both input and output DC currents for my battery bank.

My meters was purchased from SURE ELECTRONICS ebay/china back in 2009 and now they don't have the HALL EFFECT DC Current meter anymore. Wish I had purchased a couple of them back then. They are installed in a standard PVC three switch electrical box (LOWES). All cabling is using PVC flexible conduit to the battery bank main Blue sea 4-position battery switch.



My MONITOR PANEL is installed on the side of a cabinet just as you come into my trailer. Easy view both from the inside and outside standing next to the opened door.

My MONITOR PANEL is installed in a PVC 3-gang SWITCH BOX (LOWES) with the meter units glued to one of those SPECIALTY THREE-GANG SWITCH COVER. All of this is installed in a PVC Electrical BOX made for the three gang switches. I used PVC flexible conduit to route all the required cabling. My cables extend from the main BLUE SEA 4-position Battery switch just mounted very close the the installed battery bank. All lines feeding the DC MONITOR panel are fused.

This is my wiring diagram...


The only thing I really miss with this installation is an alarm when my Battery Voltage drops below a pre-set value. The TRIMETRIC RV-2025 has this feature.

Knowing the approximate charge status of my BATTERIES has been very helpful for our camping off the power grid. I want to follow the 50% to 90% charge status modes as best I can to keep my batteries in their best performance modes.

Roy Ken

Bull Rider wrote:
I bought a hand held meter, and cut the probes off of the ends of the test leads and then wired it into the 12 volt feed to the AM/FM radio. Velcroed the meter to the inside of the cabinet door next to the radio. Open the door, flip the meter to DC, and I get a readout to two decimal places.

Total cost was about ten bucks. Works for me.

Did similar except used a digital VOM that Harbor Freight gives away for free. Only cost was a little Velcro that I already had on hand.

Since I monitor what is coming out of our solar panel I use the Morningstar RM1 meter and to keep track of state of charge (SOC) use the Victron battery monitor, which will also tell you voltage...
Voltage tells you very little as it is a poor judge of SOC, unless taken some hours after no input or output for some hours. The only thing it tells you is what your converter or solar controller is doing.

I use Blue Sea Systems volt and ammeters.

I use Blue Sea Systems volt and ammeters.