Community Forums

twinglides · 03-16-2016, 08:15 PM

Changing my battery's out on my coach from wet cell to agm's and there was a small gray insulated wire wth 4 wires in it that are red, black, green, and yellow which are very small wires, the yellow and green where tied together with what looked like a small diode. The wire was connected to the negative post and when I took off the cable the wire came out of the connector, any thoughts on what it might be for.
Thanks Twin

PDR John · 03-16-2016, 08:22 PM

Temp prob for the charger portion of the inverter.

Scottybdivin · 03-16-2016, 08:28 PM

Quote:

Originally Posted by twinglides

Changing my battery's out on my coach from wet cell to agm's and there was a small gray insulated wire wth 4 wires in it that are red, black, green, and yellow which are very small wires, the yellow and green where tied together with what looked like a small diode. The wire was connected to the negative post and when I took off the cable the wire came out of the connector, any thoughts on what it might be for.
Thanks Twin

PDR John is right. I ran into the exact same scenario when I upgraded my batteries. The new ME-BTS has a shield and looks different. I replaced mine but probably could have spliced the wires with a telephone jack. I decided to run the new cable, since I had to run another one for my new ME-BMK battery monitor anyway.

twinglides · 03-16-2016, 08:29 PM

Thanks John. So is it real crucial to have it attached ? It seems that the red and black wire are not hooked to anything.

2 Stroker · 03-16-2016, 08:30 PM

X2 follow the wire, bet it goes to the inverter.
2 stroker

twinglides · 03-16-2016, 08:32 PM

Thanks Scotty looks like might be in store for a new cord.

2 Stroker · 03-16-2016, 08:34 PM

Quote:

Originally Posted by twinglides

Thanks John. So is it real crucial to have it attached ? It seems that the red and black wire are not hooked to anything.

How are you getting any power, they have to be hooked up. Yes it needs to be hooked up.
2 stroker

BrianGlenn · 03-16-2016, 08:44 PM

Battery temperature devices for inverters is probably Thermistor technology; only two wires are required with a resistor in series. The function of the resistor vs temperature is very accurate and they are low cost. Sounds like the circuit only uses the green/yellow. The inverter will have an algorithm to monitor send/receive signals and determine battery temperature via resistance in the thermistor.

Maybe more info than you were looking for,....... Sorry, the engineer in me is showing.....

Brian

Scottybdivin · 03-16-2016, 08:46 PM

Quote:

Originally Posted by twinglides

Thanks John. So is it real crucial to have it attached ? It seems that the red and black wire are not hooked to anything.

You don't have to have it connected for the charger to work. When mine came apart and I left it plugged in, the open circuit caused the inverter to think it was boiling the batteries. It wouldn't charge them higher than 12.7V. As soon as I unplugged it, it began charging normally. I left it like that for about a month until I could replace the BTS. W/o the BTS, it defaults to 72 degrees ambient temperature. The BTS is important during extreme hot or cold temperatures. That's when the charge voltage is adjusted accordingly. This information all came from Magnum customer service.

twinglides · 03-18-2016, 10:35 AM

this site is unbelievable on how fast and correct things get solved or fixed. I did order a new cable with sensor equipped and i hoping that i can splice the wire so i do not have to route it through the frame. Once again thanks for all the input.
Twin

noserider · 03-18-2016, 03:38 PM

Quote:

Originally Posted by twinglides

this site is unbelievable on how fast and correct things get solved or fixed. I did order a new cable with sensor equipped and i hoping that i can splice the wire so i do not have to route it through the frame. Once again thanks for all the input.
Twin

Yep. There is a lot of talent and experience on this board.