asked
Low voltage followed by an error 17 2x 5kw MultiPlus AGM
2x 5kw 48vMultiPlus 2x 150/85 MPPT on Can-Bus 1,000a/h AGM, BMV702. CCGX. Same scenario as seen on the other posts, low batt reported on Can bus MPPT side and then error 17. Error 17 occurring at weird times with no load, middle of night also seen. Master stopped can't invert, under codes master ok. Slave registers the error 17. Lost the master, This system is offgrid with grid connection (ignore) to use for high load and low battery only. Brand new inverters, replaced everything with new under insurance. Only one MPPT can bus type controllers replaced. Bad cabling from original install took out one charge controller, age of units ripped the lot out. Original inverters still functional . Original units ran virtual, not assistants for the grid ignore, without issue. Latest firmware in both inverters, master/slave set up. Unable to use virtual. Assistants used. BMV registered on the CAN also, with update, but unable to update BMV remote on VRM? Swapped master with slave and on power up AC in tripping. Turning off the AC out it starts up? Turning on AC in at this stage, no conflict, runs... Same error codes within 24 hours low DC and error 17. I would like to know if Can Bus is workable with this arrangement or not? Why the AC input would trip on start up? 30amp input both set to 8amps AC in. Everything we can think of and read on the other error 17's has been done, twice. Other: Stripped the battery bank 2v cells separated, to check rest voltage. 72 hours later each cell had only dropped 0.3v. Wanted to check the cell condition, this passes under load at 6kva no issue holding. Found shunt bolt stripped and repaired this. Then as above swapped master/slave arrangement around and issue occurs again. Currently on single inverter, without issue. Grabs the grid on high load, sweet. If you can add anything we have missed, we will follow. Would be good to get two back for client as it was... Cheers Rod K.
Double check the battery cables
MAKE SURE that ALL inverters have the EXACT same cable length
ie Go from batteries to a pos bus bar under the inverters and then find the longest pos run from the bus bar to inverter and make two of these the same length cables and connect.
the same applies for the Negative as well
Going back at some stage. Will critique this aspect with measuring them. They are same length with loop, will measure twice...
Can you post graphs from VRM:
-battery voltage / current
-SOC
-AC in/out
My first suspicion: battery empty and one unit stops before the other, thus giving the error.
Can you also post the assistant settings?
Could I add you to the site? Email and I will send the assistant...
I had the same, updated to the newest firmware, reinstalled asistand and redid all the settings. took my network cable first to mast from ccgx and then to slave. checked all my ribbon plugs on invertors. i also run on 2nd setting on ESS.
Its been running fine for a while now...... touch wood.
Network cables replaced, twice. Checked pins to ensure these were clamping the RJ cables...
This is my site. Rod is my distributor. Further to Rods post... who ever instalked this system used the BMV700 shunt for the negative busbar, hence the stripped bolt because he/she was too lasy to get a longer bolt. The positive has a bolt for a busbar and the only thing we havent checked is the length of the dc cables. Will do next visit. Since i broke the parallel and have run the site of one multi in standalone mode whe have had no issues. The MPPTs havent recorded low battery voltage and no erro messages. The site has grabbed the grid once in 14 days on high load (4500w for 20 sec). The battery voltage graphs are much cleaner since we reconnected after the load test. Previous they were spongey. Im wondering if there was some debries under a link bar causing the issue. Will post before and after voltage graphs tomorrow. Note the batterys dropped 0.03 of a volt over 72h when we tested them.
