Skip to main content ↑ ↓
Topic: Coach power dead when generator shuts down (Read 808 times) previous topic - next topic

Coach power dead when generator shuts down

My coach has developed an issue when dry camping without shorepower.  Autogen starts the generator when batteries have reached their lower limit.  When charge is complete and the generator shuts off all power to the coach shuts down.  No inverter or 12v power.  At this point i have put a meter on the house batteries and there is almost nothing there.  Less than 1v.  I disconnect the positive post from the battery bank and wait about 30 seconds and reconnect.  At that point I here the inverter powerup and power comes back on it the coach.  Battery voltage at the house batteries show float voltage of 13.6.  This can be replicated by simply manually starting the generator and shutting it off.  Batteries are 3 - 100ah battleborn lithium.  Any ideas would be greatly appreciated.

Re: Coach power dead when generator shuts down

Reply #1 –
Are you checking the house batteries at the batteries.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Coach power dead when generator shuts down

Reply #2 –
Yes

Re: Coach power dead when generator shuts down

Reply #3 –
Perhaps the LiFePO4 battery BMS system is shutting the batteries off for any of the reasons it would do that and that nd y disconnecting the plus cable and reconnecting it it reinitializes BMS.

This would be a good place to add high powered switches (Marinco or Blue Sea) into the neg side between the batteries and the shunt and in the positive cable between the batteries and the fuse.

Why did you disconnect the positive cable?  Generally if you want to disconnect the battery remove the negative cable first and then the positive cable.  Reconnect them positive cable first negative cable  last.

Negative cable off first and back on last.

Do you have any other charge sources? solar?  What LiFePO4 batteries?
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Coach power dead when generator shuts down

Reply #4 –
Roger,

Don't want to confuse the issue in this thread, but I noticed Steve (OP) posted a couple months ago about another electrical problem.  The first post in that thread included a rather confusing (to me) diagram of a factory "modification" to the generator charging control circuits.  I'm wondering if these two system anomalies are connected in any way?

07 Nimbus House batteries not charging on the road
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Coach power dead when generator shuts down

Reply #5 –
I agree with Roger, the BMS on the Battleborns are disconnecting the batteries.  I would watch the battery voltage to make sure it doesn't go over the shutdown voltage.  That could be caused by your charger going into equalization mode.  Or possibly your Battleborns or the internal BMS could be bad.  In that case I'd contact Battleborn and see what they say, they do have a warranty.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Coach power dead when generator shuts down

Reply #6 –
Chuck, I am not sure this is related. If the second solenoid is not engaged while the engine is running then the coach (house) batteries will not charge.  Could be the relay was wired incorrectly.  Check voltage coming into the relay.  And verify that the trigger wire that actuates the relay is getting power when it is supposed to.

Running the gen puts 120v to the inverter/charger which puts 12v to the house batteries.  This doesn't go through this part (or shouldn't)

If the voltage is low on the house batteries and the gen autostarts it could drop the LiFePO4 battery voltage low enough to trigger a BMS shutdown as well. Probably not the case.

Each battery has its own BMS.  How are they connected? Individually to a bus bar or daisy chained?
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Coach power dead when generator shuts down

Reply #7 –
Thanks all to your prompt replies. 
1. Only charge source is shore or generator.
2. The previous issue (glad you asked) was the solenoid inserted by foretravel at manufacture to deal with issues they had with 8K generator.  That solenoid had failed which caused the batteries not to charge over the road.  The solenoid replacement they sent me was the wrong one.  Got the right one and that problem was resolved.
3.  Thanks for the proper procedure for disconnecting and reconnecting batteries. I will follow that.
4.  Current situation was precipitated by failure of 2 out of the 3 battleborn batteries developing loose internal connection of the positive post on of the battery.  Those two have been removed and I'm trying to settle down the system and temporarily run on 1 battleborn until the replacements come in for the two.
5.  As a test of the BMS suggestion, which I feel might be spot on, can I remove the battleborn, and insert a lead acid 12v deep cycle from my trolling rig that is in very good condition to test this theory?

Re: Coach power dead when generator shuts down

Reply #8 –
Update.  I removed the battleborn and installed at deep cycle from my trolling setup and the generator shutdown did not affect the power to the coach.  Called Battleborn and told them this and they feel it is not their bms but want the additional batteries reinstalled after the RMA goes through and the problem will be gone they think.  Something to do with not enough resistance with only one battery being used.

Re: Coach power dead when generator shuts down

Reply #9 –
Quote from: Steve Vogel –

4.  Current situation was precipitated by failure of 2 out of the 3 battleborn batteries developing loose internal connection of the positive post on of the battery. 

So manufacturer defect of those 2 Battleborn batteries?  Are all 3 the same date/run code?  If so, I would be very suspicious of the third....
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Coach power dead when generator shuts down

Reply #10 –
Bench tested all 3 and the 1 showed no sign of loose battery post.  We tested it pretty hard.
 

Re: Coach power dead when generator shuts down

Reply #11 –
Final status of this issue.  Received 2 rma batteries from battleborn and used on to replace the one left installed that would shutoff 12v power when the generator was shutoff.  The new battery by itself did not shut down the 12v when the generator shutoff.  So the last battery is going back under an rma with a defective bms.  I think that the situation with the loose battery posts caused the bms to fail in the 3rd, non loose post, battery.