Hi Victron Community
First, system details, this is a North American 120V/12V system:
- Lynx BMS - NG with Lynx Power IN and Distributor
- qty 4, 300AHr Victron batteries
- Quattro 3000 2x120 (only leg 1 being used at 120V). Both the generator and shore power connect directly to the Quattro, with Quattro output then running into the shore power side of the existing transfer switch
- Cerbo GX w/GX50 GUI
- SmartSolar 100/30, Orion XS (not connected to Cerbo, long story…)
- All the appropriate Victron Battery Protects, and correctly sized Ancor marine wire (4/0 from battery bank to Lynx to Quattro, less than 6’ total wire length per polarity, 12’ or so total round trip), lugs, etc. I use only high quality ancillary components
- All Firmware updated to latest (558 for Quattro, came from my distributor with 558 loaded, although VC only has 556 available??)
- Installed in an 2020 Airstream Interstate w/Mercedes chassis, with a number of other devices including a Precision Circuits EMS system and Firefly control system, PC-EMS currently disconnected from the system and the Firefly appears to be running fine, with no anomalies or alarms.
I’ve encountered a problem on my latest build that I can’t seem to resolve. When testing the system with moderate 12 and 120V loads, all appears normal. However, when testing the system with it’s largest expected load, the Air Conditioner, the system resets itself within a few moments, with the Lynx BMS opening the solenoid, then resetting. I have been able to get Air Conditioner to fire up with 15A shore power connected (15A input limit, only used 8.5 amps and assisted… seemed a bit odd), then removing shore power and it’ll run off inverted power and the full load was on the order of 1300W. Well within the Quattro’s capability, even considering inrush. Even if inrush overloaded the Quattro, this shouldn’t reset the system. When this occurs I see error W-B10: VE Can disconnected. I’ve inspected the female connections (they look fine and have no debris inside, no bent pins), am using Victron cables and have swapped out cables and terminators to rule out a bad cable. I even tried running a new cable far away from any other wires, to rule out interference. Any ideas of what else I can check or tests I can run to determine root cause? Could I have a bad Lynx BMS?
Update and issue closed! The VE Can error was occurring because the BMS was momentarily cutting power and resetting the Cerbo, which momentarily cut VE Can coms. I ended up bypassing the OEM transfer switch, that had some sort of relay attached to it. The schematic shows the device, but doesn’t detail why it’s there, what it does or what triggers it. It references another Eng print that’s not in the AS package. Airstream wouldn’t tell me what it did, and simply said “if you’re modifying the system all we can give you is the schematic”. Frustrating, but I get it. Now everything works just fine.