I have used some Victron product in the past for small Solar applications but I’m not very familiar with the Orion line of DC to DC Chargers. I recently decided to upgrade my single Lead Acid House battery to 2 100AH Lithium batteries in parallel, after a bit of research I found out that the common Automatic Charge Relays are not a good idea with lithium so I found the Orion XS seems like the right part for the job, however I’m not certain which led me here. I created 2 drawings, the first is my current config in operation on the boat, the second drawing is what I think will work using the new lithiums and the Orion chargers. I tried to keep the drawing simple so I didn’t clutter it up with things like fuses, breakers, etc. that are obvious.
I would like to get the community’s opinion on the design? Anything that jumps out as wrong, a bad idea, could use improvement or suggestions of alternative products would be greatly appreciated!
I think that the system as drawn will work OK. You have your Orions connected up correctly, you have the shunt connected up correctly. The emergency switch could result in a high current flow from lithiums if the start batteries were dead. Also, if left closed with engines running the alternators voltage could cause a high voltage shutdown on the lithium BMS so care is needed in use.
I realize the emergency switch when in the 1 + 2 position could cause problems, the idea is if needed it would be used just to start the engines then quickly disconnected. I guess as an alternative to the switch I could use a relay triggered by a momentary switch at the helm, that way the button could be held long enough to start the engines then released. Do you know of a victron product that would be a better solution to the emergency switch function?
You said “I think that the system as drawn will work OK”, is there anything you would do differently? I really appreciate your expert opinion.
Just hedging my response, I have not dealt with twin engine boats before, so just cautious just in case I am missing domething esoteric, I don’t think do, it all looks good.
To address the issue with the emergency switch being accidentally left on the 1 + 2 position, I think I will use a Smart Battery Protect in switch mode and mount a momentary switch at the helm close to the key switch.
The manual does not say anything about a delay when the switch is closed or opened, do you know if there is any delay like when using a switch on the H input?
You can not do this because the Battery Protect only functions in one direction and on your emergency cross connect you could have current flow in either direction once the engine(s) are running. From the manual
Pay attention to the correct orientation. The BP is designed to allow current to flow from IN (battery) to OUT (load) terminals only. Reverse currents from OUT to IN terminals are strictly forbidden and will damage the device.
I understood the BP only works in one direction but I did not realize current coming in on the out would cause damage, I guess I assumed it was diode protected.
Ok, so instead I could use a generic 100A relay instead.
