Hi, I have recently had a GivEnergy system installed with 2 off 5.2kw batteries. I have had the circuit breaker trip out a few times when the load on the batteries is around 3.5 kw. Any one got any ideas why this would be? Thanks Graham
GY poor connection on the breaker perhaps. A common install error is not stripping the wire back properly and thus clamping part of the wires cover rather than just wire.
Could also be a faulty breaker.
Best to get your installer back.
which breaker/where? Is it MCB (load) or is it RCD (fault)?
100A is a big breaker so if it tripping on load that is quite a big load, Can the inverter actually deliver that?
SteveCook It is a big breaker but I assume the OP is talking about the DC MCB. 3500W @ 50v is around 70amps current so big breakers are required. That kind of load should be fine but as TX200 says it may not be installed correctly and there is not enough wire profile in contact/too much resistance or indeed the MCB is faulty.
killythebid
Thanks so is that the breaker on the side off the battery?
Dont GivEnergy use pre wired cables/plugs between battery and inverter, or is that just newer stuff?
GY When this happened to me I found that I could tighten up the screw terminals a bit and the problem went away.
SteveCook The 5.2kWh batteries do not have a breaker on the side. They will have a seperate DC MCB fitted between the Inverter and the batteries. The connections will be bare wire into the MCB and it is vital that a good (tightened to spec) clean connection is made as a poor one will reduce voltage and increase amps potentially tripping the MCB and could get quite hot along the way
killythebid
Thanks so proper installation and termination of cables likley cause
Thanks for your help, i will just check the terminals are tight on the cables. If it continues i will contact the installer.
GY Be careful that as the battery may well still have DC charge and the cable terminations you tighten may well be "live"
GY Hi GY, I am experiencing very similar issue with mine. I have replaced the MCB but the tripping issue still persist. I am not sure what to be done. When i was replacing the MCB i noticed one of the cable connecting the battery to MCB has become black. Do you think it has to do with the Cable? Have you got your problem solved?
UpendraGummitha Discolouration of modern cable insulation is a sign of overheating due to being underrated or arcing due to a break in the internal wire or insulation or a loose connection if it is the end that is discoloured. Insulation on domestic wiring is usually rated to max 90C but if it gets above 70C for a long time it will degrade. I would suggest you get an electrician to check urgently and replace the cable. Whilst not easy to ignite it is still a potential fire.
Windy Miller I had to do this again as my DC breaker dropped out twice whilst exporting the battery at full pelt. So it isn't just an installation error. There must be some sort of creepage as I could tighten them up again where I had done this last year.
Windy Miller So it isn't just an installation error.
It is just an installation error. There are instructions and ferrules supplied with the DC MCB.
Check that the ferrules are correctly fitted to the ends of the cables. I would recommend using a square type crimper. Here is an example (look at ALL the pictures):
https://www.amazon.co.uk/Lytool-0-08-16mm%C2%B2-Crimping-Bootlace-Self-Adjustable/dp/B0DRN4C6P7/
Then the connections must be tightened using a Torque Screwdriver to the torque given in the instructions (I think 3.5Nm). This is a torque screwdriver.
https://www.amazon.co.uk/Draper-Interchangeable-Torque-Screwdriver-Multi-Colour/dp/B00UJJ8I3I/
If it has been allowed to overheat, the correct solution is to replace the breaker and all 4 cables. You will need ferrules and ring crimps for the inverter end (and a crimper to fit those).
This seems beyond the capabilities of some installers, so GivEnergy no longer use this method of connection.