Hello all
I have bought 2 din rail consumer boards for my motorhome. One for mains and one for dc.
The mains one has 2 rcd’s and a change over switch to switch between shore mains and inverter mains. Live and neutral are both switched.
One rcd is for inverter power, one rcd is for shore power. The change over switch is after the two rcd’s.
The battery charger for the leisure batteries has its own trip and is connected permanently to the shore power. This does not change over. This is why I bought 2 rcd’s as there is potentially a circumstance where 2 are needed.
All the other provisions do change over.
My question is about safety and the functioning of the rcd(s).
On shore power it’s easy, I leave earth, live and neutral as is. Maybe make my own earth in the ground with a rod.
However, the inverter power is more difficult.
For the earth when I am on inverter power should I just leave as is from the inverter live, neutral and earth, or permanently tie the earth to the neutral on the inverter, or should I copy what I saw someone else had done and use a relay to connect earth to neutral just when on inverter power?
I will be using an earthed microwave oven (not double insulated) and a coffee machine that requires earth.
I am unsure what will happen if I connect the mains earth to the vehicle chassis also which I would like to do as the vehicle chassis is negative battery terminal and I have a non isolated controller to charge the leisure batteries from the alternator.
I would like to use the inverter while I am driving to get mains for my sound bar under the tv, charge laptops, use high power usb c pd charges etc.
The only thing I am sure I shouldn’t do is connect shore earth to shore neutral as if the external supply has an rcd this could trip it.
I suspect you are all going to ask me about the specifications of my inverter, which is not a top brand but I dont want to replace it yet as I might dump the whole 12v high current solar system and go for a 24v or 48v system with additional kit to charge from the vehicle 12v system alternator. Essentially a buck (24v or 48v for 12v pumps and lights) and a boost to use alternator to charge 24v/48v batteries.
What I would like is one of those plug-in mains testers with a small load to test tripping an rcd to behave the same as in a normal domestic installation. So all the lights on the tester behave in the right way. And it trips when it should.
That is for both inverter power and shore power.
What do you all think?
You can start with marks out of 10 for understanding/not understanding the relevant concepts if you like!
I am aware your all likely to tell me to put my inverter on a bench and test it first. And watch out for grey smoke.
I have bought 2 din rail consumer boards for my motorhome. One for mains and one for dc.
The mains one has 2 rcd’s and a change over switch to switch between shore mains and inverter mains. Live and neutral are both switched.
One rcd is for inverter power, one rcd is for shore power. The change over switch is after the two rcd’s.
The battery charger for the leisure batteries has its own trip and is connected permanently to the shore power. This does not change over. This is why I bought 2 rcd’s as there is potentially a circumstance where 2 are needed.
All the other provisions do change over.
My question is about safety and the functioning of the rcd(s).
On shore power it’s easy, I leave earth, live and neutral as is. Maybe make my own earth in the ground with a rod.
However, the inverter power is more difficult.
For the earth when I am on inverter power should I just leave as is from the inverter live, neutral and earth, or permanently tie the earth to the neutral on the inverter, or should I copy what I saw someone else had done and use a relay to connect earth to neutral just when on inverter power?
I will be using an earthed microwave oven (not double insulated) and a coffee machine that requires earth.
I am unsure what will happen if I connect the mains earth to the vehicle chassis also which I would like to do as the vehicle chassis is negative battery terminal and I have a non isolated controller to charge the leisure batteries from the alternator.
I would like to use the inverter while I am driving to get mains for my sound bar under the tv, charge laptops, use high power usb c pd charges etc.
The only thing I am sure I shouldn’t do is connect shore earth to shore neutral as if the external supply has an rcd this could trip it.
I suspect you are all going to ask me about the specifications of my inverter, which is not a top brand but I dont want to replace it yet as I might dump the whole 12v high current solar system and go for a 24v or 48v system with additional kit to charge from the vehicle 12v system alternator. Essentially a buck (24v or 48v for 12v pumps and lights) and a boost to use alternator to charge 24v/48v batteries.
What I would like is one of those plug-in mains testers with a small load to test tripping an rcd to behave the same as in a normal domestic installation. So all the lights on the tester behave in the right way. And it trips when it should.
That is for both inverter power and shore power.
What do you all think?
You can start with marks out of 10 for understanding/not understanding the relevant concepts if you like!
I am aware your all likely to tell me to put my inverter on a bench and test it first. And watch out for grey smoke.
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