Be careful with a flat battery and a Voltage Sensing Relay..

[wipe_out]

We have a VSR between the engine and domestic batteries (and another from domestic to bow thruster).. An issue we has the other day was that something had been left on and it flattened the domestic battery to 8.2v.. The VSR has a lockout at 9.5v (which I just discovered) so even with the engine running and charging at 14.2v the relay never closed and so the battery would not charge.. This meant the plotter would not run, nor would anything else on the domestic side..

The solution was to use a piece of wire and bridge the engine and domestic positive terminals.. Doing this for about 30sec caused the relay to see a high enough voltage and so close and from there on the battery charged up and all was good..

So going forward I am planing on adding a method of bridging the positives without having to empty the storage to gain access to the back of the battery isolator switches in case this ever happens again..

Just thought I would post for anyone else who uses VSR's to charge multiple battery banks..

 

[aquapower]

We have a VSR between the engine and domestic batteries (and another from domestic to bow thruster).. An issue we has the other day was that something had been left on and it flattened the domestic battery to 8.2v.. The VSR has a lockout at 9.5v (which I just discovered) so even with the engine running and charging at 14.2v the relay never closed and so the battery would not charge.. This meant the plotter would not run, nor would anything else on the domestic side..

The solution was to use a piece of wire and bridge the engine and domestic positive terminals.. Doing this for about 30sec caused the relay to see a high enough voltage and so close and from there on the battery charged up and all was good..

So going forward I am planing on adding a method of bridging the positives without having to empty the storage to gain access to the back of the battery isolator switches in case this ever happens again..

Just thought I would post for anyone else who uses VSR's to charge multiple battery banks..

Which make of VSR do you have ? My boat has Victron Cyrix i with option to link but I have not connected that up.

www.victronenergy.com/upload/documents/Manual-ENNL-Cyrix 100.pdf

 

[wipe_out]

Which make of VSR do you have ? My boat has Victron Cyrix i with option to link but I have not connected that up.

www.victronenergy.com/upload/documents/Manual-ENNL-Cyrix 100.pdf

I have the Blue Sea SI series, has the option to force the relay open but not an option to close it..
https://www.bluesea.com/products/7610/SI-ACR_Automatic_Charging_Relay_-_12_24V_DC_120A

 

[aquapower]

I have the Blue Sea SI series, has the option to force the relay open but not an option to close it..
https://www.bluesea.com/products/7610/SI-ACR_Automatic_Charging_Relay_-_12_24V_DC_120A

Thanks, I have used them as well and found to be reliable.

 

[Paul_S123]

I have the Blue Sea set up too. This happened to me with my house batteries too. Not sure if you have a way to combine batteries for an all battery start on your set up, but all I did was to turn my Blue Sea battery switch to combine, for a few seconds and that allowed them all to charge. I was then able to put the main switch back to it's normal position and the VSR kicked in as normal.

 

[guyd]

I've had odd issues with a bep 24v marine vsr in my camper van, trashing 4 X 180ah batteries..... :^)