Inverter Numbers?

Howdy guys, your local rookie here. I just finished training and am working on getting a truck assignment, but having a bit of a hickup in using the outlets/heat. When the truck is running, the little inverter label in the sleeper reads 14.0, but almost instantly when I turn it off, the reading goes down to 11.1-11.4 and an alarm starts going off that reads "EOS", so I can't use my fridge or microwave, or hell even plug in my phone without the alarm going so I just turn it off. The heater in the sleeper even turned off last night about 2 am in Indianapolis (rather chilly wake up call), reading low voltage. My trainer said the batteries just needed to be charged, nothing to worry about, so I've idled it approx 45 minutes, and the same issue. I have no idea what I'm doing, and I'm not sure if it's a me problem, or if this already needs to be in the shop. If you can help me out, or even just let me know the numbers that yours shows, that would be great thanks everybody.

It is Cooper bussmann model 12-110-1800 if that is of any help

Sounds like bad batteries or the apu isn't keeping them charged.

APU:

Auxiliary Power Unit

On tractor trailers, and APU is a small diesel engine that powers a heat and air conditioning unit while charging the truck's main batteries at the same time. This allows the driver to remain comfortable in the cab and have access to electric power without running the main truck engine.

Having an APU helps save money in fuel costs and saves wear and tear on the main engine, though they tend to be expensive to install and maintain. Therefore only a very small percentage of the trucks on the road today come equipped with an APU.

Sounds like bad batteries or the apu isn't keeping them charged.

I agree, your batteries are bad. It reads 14.0 while the truck is running because that is what your alternator is producing, like it should. When the truck is turned off it should continue to read in the 12.8ish range until it starts dropping due to load. I can watch a 22 inch tv, have an LED light strip on, bunk heater and my 40qt cooler plugged all while the truck is off and wont need to restart till about the 12.1volt reading on my inverter which shows about 11.7-12.0 on tit's cold. That is after a couple of 2-4 hours of usage. I unplug the cooler at night. What does the trucks volt meter show on the instrument panel? It should be pretty accurate. However if you are showing the EOS code and stuff is shutting off it is because your batteries are too low and the truck is designed to shut off different items to maintain some charge. If you don't get the batteries changed you will end up cold as hell once the heater shuts off and the batteries are too low to start the truck. Waiting a few hours for a jump start sucks when its cold.

OWI:

Operating While Intoxicated

APU:

Auxiliary Power Unit

On tractor trailers, and APU is a small diesel engine that powers a heat and air conditioning unit while charging the truck's main batteries at the same time. This allows the driver to remain comfortable in the cab and have access to electric power without running the main truck engine.

Having an APU helps save money in fuel costs and saves wear and tear on the main engine, though they tend to be expensive to install and maintain. Therefore only a very small percentage of the trucks on the road today come equipped with an APU.

Thank you guys, sounds like she's off to the shop already

Is 2-4 hours pretty normal before needing to idle the truck? I guess I just assumed you could leave stuff plugged in 24/7 and driving during the day charged it up enough

Thank you guys, sounds like she's off to the shop already

Is 2-4 hours pretty normal before needing to idle the truck? I guess I just assumed you could leave stuff plugged in 24/7 and driving during the day charged it up enough

Depends on what you have on and if your truck has an APU or opti-idle, mine does not so starting the truck is the only way I have to recharge them. The coolers especially pull a fair amount of current. I try to start it when my inverter shows about 12.1-12.2, that's usually about 11.8 on the dash. If it gets around 11.6 or below on the dash you run the risk of not starting. If you are not running extras you dont need to worry about it running the batteries down. But always keep an eye on it. 2-4 hours is about normal for me, you will have to keep an eye on your truck to find out what's normal for you. I have new batteries also. I do recommend you unplug the cooler before bed if you are using an iceless cooler, if you have a built in fridge don't worry about it.

Something important, don't run the microwave without the truck running. It pulls way too much current and will ruin the batteries.

APU:

Auxiliary Power Unit

On tractor trailers, and APU is a small diesel engine that powers a heat and air conditioning unit while charging the truck's main batteries at the same time. This allows the driver to remain comfortable in the cab and have access to electric power without running the main truck engine.

Having an APU helps save money in fuel costs and saves wear and tear on the main engine, though they tend to be expensive to install and maintain. Therefore only a very small percentage of the trucks on the road today come equipped with an APU.