Well...took the van away for a 3 night stay with some friends off grid. I hadn't been in the van for about 8 weeks, not since keeping it in storage while not plugged in to the mains. I had upgraded the house battery pack a while back from the factory 1 x 100amp AGM, to 2 x 140 amp AGM's and had used it a few times with that setup.
I had put the van on to power about 24 hours prior to leaving to get the fridge up and running...and pump a few amps back in to the batteries before heading off...all good...the fridge was cold when hooked up...and stayed that way on 12v from the tug to destination.
Anyway, got to camp late morning first day, set up, fridge and water heater fired up on gas, the 12v would only be running lights and water pump. I was not concerned about the 12v and didn't really pay a lot of attention to what the battery reading was on the panel on arrival...but pretty sure it was reading around 12.6v - 12.7v...should have been ok. That night the shower got used a couple of times, and some lights on...no great power usage. The "power left" indicator usually reads about 199 hours with the battery set up while using only a couple of LED's.
Following night at around 8pm all lights went out? The BMS must have switched off the power due to low battery...huh? That was only maybe 6 hours all up of lights usage! So I switched off the lights and also the battery 12v isolator for a bit then switched it all back on and had power to use the water pump to shower and some lights again. I turned off the battery isolator again over night to save on what ever charge was still there.
I am thinking the batteries must not have been fully charged, as there is no way it should have cut out after only a few hours usage.
So in the morning I found the fridge was off...fantastic...so it seems if you turn off the 12v supply the fridge, it will turn off even if on gas as it appears the "smart" fridge still needs a 12v feed to allow it operate on gas....well I'll be!
Next day I connected my 400w of external solar panels to the van as it was in the shade until after midday so the puny 160w panel on the roof wasn't doing much at all. I hadn't tried out my new set up,
I had attached an Anderson plug to the tool box up front and run wiring under the van back in to the battery compartment under the seats, added a 40 amp MPPT charger with Anderson plug to plug in to the batteries when utilised. All worked fine and was pumping amps back in to the batteries, the battery monitor was showing 13.2 volts in no time. But...of course as the new solar regulator was connected directly to the batteries the BMS wasn't recognising that there was charge going in to the batteries, only the charge in the batteries, so the monitor did not show any of that info, nor did the battery condition indicator reach "full"...even though it should have done.
I was aware I had to connect any additional inputs or outputs via the negative terminal on the BMS if I wanted to have correct info of power in and out showing up on the monitor, So after this little issue I have bought a Shunt from BMPro...Not cheap I might add, to connect between the negative terminal on the battery to all cabling...so the BMS should "see" the second solar regulator and give me correct readouts on the monitor. I plan to install an Inverter so that too can connect via the Shunt and should give me readouts of what is going out at any time.
Is there anything else I need to do to make this all function as expected? I am heading off grid for another 4 days in a couple of weeks so will be able to put to the test. I am aware too that the solar regulator in the BMS may be affected by the second solar regulator and vice versa and either one go in float mode earlier than it should...but have a way to fix that if it does occur...
Cheers
I had put the van on to power about 24 hours prior to leaving to get the fridge up and running...and pump a few amps back in to the batteries before heading off...all good...the fridge was cold when hooked up...and stayed that way on 12v from the tug to destination.
Anyway, got to camp late morning first day, set up, fridge and water heater fired up on gas, the 12v would only be running lights and water pump. I was not concerned about the 12v and didn't really pay a lot of attention to what the battery reading was on the panel on arrival...but pretty sure it was reading around 12.6v - 12.7v...should have been ok. That night the shower got used a couple of times, and some lights on...no great power usage. The "power left" indicator usually reads about 199 hours with the battery set up while using only a couple of LED's.
Following night at around 8pm all lights went out? The BMS must have switched off the power due to low battery...huh? That was only maybe 6 hours all up of lights usage! So I switched off the lights and also the battery 12v isolator for a bit then switched it all back on and had power to use the water pump to shower and some lights again. I turned off the battery isolator again over night to save on what ever charge was still there.
I am thinking the batteries must not have been fully charged, as there is no way it should have cut out after only a few hours usage.
So in the morning I found the fridge was off...fantastic...so it seems if you turn off the 12v supply the fridge, it will turn off even if on gas as it appears the "smart" fridge still needs a 12v feed to allow it operate on gas....well I'll be!
Next day I connected my 400w of external solar panels to the van as it was in the shade until after midday so the puny 160w panel on the roof wasn't doing much at all. I hadn't tried out my new set up,
I had attached an Anderson plug to the tool box up front and run wiring under the van back in to the battery compartment under the seats, added a 40 amp MPPT charger with Anderson plug to plug in to the batteries when utilised. All worked fine and was pumping amps back in to the batteries, the battery monitor was showing 13.2 volts in no time. But...of course as the new solar regulator was connected directly to the batteries the BMS wasn't recognising that there was charge going in to the batteries, only the charge in the batteries, so the monitor did not show any of that info, nor did the battery condition indicator reach "full"...even though it should have done.
I was aware I had to connect any additional inputs or outputs via the negative terminal on the BMS if I wanted to have correct info of power in and out showing up on the monitor, So after this little issue I have bought a Shunt from BMPro...Not cheap I might add, to connect between the negative terminal on the battery to all cabling...so the BMS should "see" the second solar regulator and give me correct readouts on the monitor. I plan to install an Inverter so that too can connect via the Shunt and should give me readouts of what is going out at any time.
Is there anything else I need to do to make this all function as expected? I am heading off grid for another 4 days in a couple of weeks so will be able to put to the test. I am aware too that the solar regulator in the BMS may be affected by the second solar regulator and vice versa and either one go in float mode earlier than it should...but have a way to fix that if it does occur...
Cheers