This is guess work atthis point becasue I dont have the manual in front of me. and it doesnt have a circuit diagram.Quote:
Originally Posted by d2dave
The earth wire needs to be at least the same size as the power wire as in the event of a fault to earth it needs to carry the full current of the power supply. in the setup that Im guessing this system provides its protection by relying on an active to earth fault shorting out the inverter.
the second image shows this. The loop wire that runs from neutral back to earth (which is the wire that you want to know what to do with) and what you do with that is tie it to the main earth point for the mains power of the van.
This is where my concern about how the van is earthed comes in. If the DC earth goes to the chassis AND the main earth ties to the chassis you can wind up with some interesting and, in the devils advocate worst case scenario scene, potentially fatal results if the inverter is not designed to operate with the DC and mains output Earth tied together.In most cases it simply results in the inverter faulting and requiring the fault to be rectified, sometimes fuses replaced but in some cases the inverter will just let its smoke out.
The reason they dont put the link in internally is because it provides part of the protection of the system and depending on how you install it you may not need it (for example if you patch it in correctly using an external RCD). The diagram setup shows the simplest and cheapest method that should work reliably if you build it up correctly.
Old school earth wiring required that the earth wire be able to carry the full current as it works as this inverter is configured to work, any fault from the active to the protective earth carried the current back to the MEN point effectively dead shorting the fuse and blowing it. This had issues because if you had a broken earth wire in an appliance that had a short to its body, were touching that appliance and then touched another that would then cause your body to carry the full current available till the fuse blew.
with the new system the RCD detects a much much lower fault current by means of white man magic, as the current rate is lower the cable can be smaller but it needs to have a lower resistance.
IF you were to wire up this inverter via an RCD and it had the internal link you would effectively be bypassing the RCD.
for the earth wiring to a 3 pin socket Im guessing that it wants you to run the earth from your chassis ground to the socket
IMHO
the quality of the manual should be the first indicator that perhaps you might not want to buy this inverter..... but that said.
I know how I would wire up that inverter but as I'm not certified to do install work I cant legally tell you. Im still going to stand by my previous advise of getting an inverter that has an AUS socket on it and run directly off of that without patching into the mains OR by running a lead to the van power inlet, but I'll up the ante if all your wanting it for is to charge a laptop and run some lights.
Convert all your lights to 12v DC stuff and run them off the batteries, put a charger in with the batteries and wire that to the mains inside the van get really clever and have the AC input drive a contactor that then completes the chargers circuit to the battery. For the laptop purchase a straight DC-DC charger and install a socket to suit. It will be more effecient and Id bet that if you were charging your laptop and operating it at the same time you'll be drawing more than the 1.2A@240v that that inverter would happily deliver.
