question

jokani avatar image
jokani asked

Dual DC Bus System for Lithium + Multiplus

With both a charge and load bus, am I Ok to connect the Multiplus to the charge side, then if the load contactor trips, the Multiplus will be disconnected, I'll lose 240v inverter power, but the 12v loads will remain?

MultiPlus Quattro Inverter Charger
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

3 Answers
Mike Dorsett avatar image
Mike Dorsett answered ·

Hi Jokani,

The only reason why not to do this would be that the multi could operate in invert mode and discharge the battery whilst the REC has the load contactor switched off (i.e. low SOC). The BCP220 is also redundant in the load distribution as the REC will turn off the loads also - covering the BCP's function. I would also wire the "always on" loads (i.e. emergency LED lights only) direct to the battery, via their own fuse, so even at low soc you are not plunged into darkness when the load contactor opens. You might want to use the BCP in the main load distribution to achieve a 2 stage load shed, i.e. cutting off heavy consumers such as Fridge freezer radar, but NOT auto pilot and nav systems. It could also be possible to add an alarm relay to this to warn of impending low SOC event. This could also be wired into the multi to stop it from inverterting, and put it in charger only mode. Mike.

1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

jokani avatar image jokani commented ·
Wow, that is some really good advice, much appreciated, thank you.
0 Likes 0 ·
Mike Dorsett avatar image
Mike Dorsett answered ·

Hi Jokani, Your question is not realy clear. Is it possible for you to draw a schematic. Are the load and charge buses AC or DC? How are they connected to the battery if DC?

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

jokani avatar image
jokani answered ·

Hi Mike, this is still work in progress, all DC:

work-in-progress.jpg


work-in-progress.jpg (179.4 KiB)
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.