Why does my main house consumer unit trip when the inverter switched to AC backup?

[marconi]

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Have you an Ohmmeter/multimeter? Do know how to use it to measure resistance?

 

[davesparks]

What disconnects the installation from the DNO supply when the inverter is connected?

 

[marconi]

Is this the boxed system you have or something similar?

 

[DPG]

What disconnects the installation from the DNO supply when the inverter is connected?

That was what I was asking about yesterday when I asked about relays and isolation. But I posted it in the wrong thread! Doh

 

[Tonyboy]

Is this the boxed system you have or something similar?

Hi Marconi and davesparks

Yes the cabinet is similar to the one in the picture, it is from the same people. It is connected to the mains via a side input and in the event the power goes of the soft start relay cuts off the power to the inverter. I disconnect it from the mains manually if I don't want utility power to provide any input but it can be left on and it comes in when the timer is set to use utility.
The battery will still supply power to the solar consumer unit via the inverter when it is set to in the program but it cannot go back to the main supply as this either disconnects when the power goes off, and as the output from the inverter only goes to the solar output consumer unit
In terms of it disconnecting from the main supply in normal use I think the supply side stays connected but not used and it only powers the inverter when the timer calls for ac from the ac input.
Yes I have a multi meter I used it to check the resistance of the earth cable to the rod when I installed that.
Tell me more please!
regards

Tonyboy

 

[marconi]

The switching inside the inverter box is normally done by solid state switches to ensure no-break of supply when moving between mains to output or inverter to output.

Tonyboy - where have you happened upon the term TN-S? I suspect what you have bought or set up is an off grid systemwith genie back up to the inverter mains input. This would require the inverter output to be made tn-s in order for automatic disconnection of the inverter supply to the output socket in the event of an earth fault. This would be done on the inverter output. For uk mains input in lieu of genie one cannot link the output N with Cpc/earth/pe for the reason I mentioned earlier.

 

[Tonyboy]

The switching inside the inverter box is normally done by solid state switches to ensure no-break of supply when moving between mains to output or inverter to output.

Tonyboy - where have you happened upon the term TN-S? I suspect what you have bought or set up is an off grid input with genie back up to the inverter mains input. This would require the inverter output to be made tn-s in order for automatic disconnection of the inverter supply to the output socket in the event of an earth fault. This would be done on the inverter output. For uk mains input in lieu of genie one cannot link the output N with Cpc/earth/pe for the reason I mentioned earlier.

Hi Marconi
The description of the inverter outputs says it has a TN-S arrangement and when I purchased it I was told it was suitable to connect the mains as a standby/ additional source of charging power for overnight cheap rate electric.
It is indeed an off grid solar supplied unit with either standby genie or mains power to charge the batteries overnight.
Is there a solution to the issue of the cabinet being TN-S and does it involve changing or adding anything else to the system to rectify the issue. Currently I am having an issue with the inverter showing an F12 fault so I think that it will be going back to the supplier next week, however given they are selling this unit with the specific option of direct connection to a mains supply I had really expected it to work once it was connected.
I am content to change things if it will sort the problem but I don't want to be having to alter stuff in the cabinet as it is all pre wired and supposedly plug and play.
Many thanks again

tonyboy

 

[marconi]

Please see attached electrical art. Please study and note my remarks beside the three balloons. The ohmmeter tests at A, B,C and D must be done with all sources of electrical energy ie mains, battery and pv panels isolated. With ohmmeter set to low range eg 0 to 200 measure between N and E/cpc and tell me results.

 

[Tonyboy]

Please see attached electrical art. Please study and note my remarks beside the three balloons. The ohmmeter tests at A, B,C and D must be done with all sources of electrical energy ie mains, battery and pv panels isolated. With ohmmeter set to low range eg 0 to 200 measure between N and E/cpc and tell me results.

Hi Marconi
I think this will take me some time to do, as I will need to get access to the mains in my house and I am assuming the insides of the cabinet trunking and connections. To be honest it may be more than difficult to start dismantling the internal components of the cabinet as its all concealed, I will get in the cabinet and see what I can access and hopefully get back to you soon, I am working over the next three days on odd shifts so it may not be until the weekend or Monday.
I am assuming I is the inverter and the consumer unit on the right is my solar out unit.
Thanks for taking the time to do the drawing, I am very grateful.
My fears at present are that I am going to have to do some serious alterations to the set up and that was why I got a self contained cabinet to avoid this.

Quick edit I measured the point (b and c) before and after the rcd and got 00.2 for both and the consumer unit (D) with feed unplugged and all both on and off and got no reading. The main consumer unit is in a built in cupboard over the door and will take some getting to, so it may take me a while to get reading A.

We will see.
Regards

Tonyboy

 

[marconi]

What literature do you have that you can send me or a link to? Do you have a circuit diagram for the cabinet?

If your cabinet has on one side as in the earlier video clip two c forms for mains in and inverter out then I can spell out a way to do the measurements at the socket or plug N and E pins without dismantling anything. But that will be tomorrow because I am starting to cook for visitors tonight.