RooiWillie Posted January 28, 2016 Share Posted January 28, 2016 Hi Guys, I got myself a Proline Energy 3kVA inverter as a backup power source - in case of load shedding or whatever. I used to use a Mecer 1200VA inverter, and it was working well, bar being modified sine. The main use for my setup, is my office, I work from home and cannot afford to sit in the dark. So the idea was simple, replace the Mecer with the Proline, in a temporary install. Reason for this is that we rent our place, and I'm for sure not one to invest in a backup system, just to leave it here when we move. So I build a trolley that hosts both the inverter and has space for 6 batteries. All looked well and I connected the wiring, just to have it trip the earth leakage in my office. My office is actually one of the out buildings, so its fed from the main DB in house, to a smaller DB in the office, with an earth leakage and 2 breakers - each for a plug in the office. One of these plugs feeds the inverter: Here is the problem, if the inverter is plugged in and off, it charges the batteries until full, at which time the fans stop running and all seems to be in standby. As soon as I switch the inverter on, it trips the earth leakage in my office. Note, there is no load (i.e. nothing plugged in). Any ideas why? Quote Link to comment Share on other sites More sharing options...
Guest Posted January 28, 2016 Share Posted January 28, 2016 Welcome Rooi Willie. Off the top of my head: - I presume the wires are correctly connected?- And the output of the inverter, is connected to your equipment? Quote Link to comment Share on other sites More sharing options...
viper_za Posted January 28, 2016 Share Posted January 28, 2016 Welcome to the forum RooiWillie It sounds to me like you are feeding the inverter from behind your earth leakage. The AC input needs to be supplied before your earth leakage. Then your earth leakage should be on the AC output of the inverter. Thys SOLARWIND 1 Quote Link to comment Share on other sites More sharing options...
RooiWillie Posted January 28, 2016 Author Share Posted January 28, 2016 Thank you for the welcoming guys! Welcome to the forum RooiWillie It sounds to me like you are feeding the inverter from behind your earth leakage. The AC input needs to be supplied before your earth leakage. Then your earth leakage should be on the AC output of the inverter. Thys That is indeed correct. How should I go about it then, add a separate earth leakage between the inverter and equipment? And then not connect the earth of the inverter? Welcome Rooi Willie. Off the top of my head: - I presume the wires are correctly connected?- And the output of the inverter, is connected to your equipment? 1. Checked those many times, up to the point where only the inverter was connected via plug to the mains. 2. Supposed to, but not yet - I just wanted to check if the inverter powered up and charged the batteries. Quote Link to comment Share on other sites More sharing options...
superdiy Posted January 28, 2016 Share Posted January 28, 2016 Hi Rooiwillie Who did the connections on the inverter? If the Neutral and Earth on the inverter output is bonded (connected together) it will cause the ELR to trip when the inverter runs in bypass mode - ESKOM supplies the load. The safest way to do this trolley installation, is to feed the inverter from a circuit connected before the current ELR (in the DB) and then to bond Neutral and Earth on the inverter output and feed the inverter output through another ELR to the load. The less safe option is to ensure that there is no Neutral - Earth bond on the inverter output - that should not cause the ELR to trip, unless something is wrong somewhere, either inside the inverter, or with a connection somewhere. Quote Link to comment Share on other sites More sharing options...
Guest Posted January 28, 2016 Share Posted January 28, 2016 SuperDIY, are these inverters not supposed to be plug an play, when not wired into the DB board? Quote Link to comment Share on other sites More sharing options...
RooiWillie Posted January 28, 2016 Author Share Posted January 28, 2016 Hi Rooiwillie Who did the connections on the inverter? If the Neutral and Earth on the inverter output is bonded (connected together) it will cause the ELR to trip when the inverter runs in bypass mode - ESKOM supplies the load. The safest way to do this trolley installation, is to feed the inverter from a circuit connected before the current ELR (in the DB) and then to bond Neutral and Earth on the inverter output and feed the inverter output through another ELR to the load. The less safe option is to ensure that there is no Neutral - Earth bond on the inverter output - that should not cause the ELR to trip, unless something is wrong somewhere, either inside the inverter, or with a connection somewhere. I did these connections. Sadly, there is no way to add it before the ELR, unless I plan on leaving the unit installed in the rent house - and that is not an option. Adding an ELR in after the inverter is no problem though. Quote Link to comment Share on other sites More sharing options...
RooiWillie Posted January 28, 2016 Author Share Posted January 28, 2016 How about this, inverter chassis earthed via plug (as if its an appliance), and then bonded earth and neutral to ELR to downstream connections form inverter? Quote Link to comment Share on other sites More sharing options...
___ Posted January 28, 2016 Share Posted January 28, 2016 How about this, inverter chassis earthed via plug (as if its an appliance), and then bonded earth and neutral to ELR to downstream connections form inverter?You're going to have the same problem. Any connection between neutral and earth is going to cause an upstream rcb to trip.The only inverter I know with a workaround for this is the Victron Multiplus/Quattro. It has a bonding relay that opens while in bypass, and closes in invert mode. So it works downstream from another RCB, in fact mine is set up like that. Sent from my GT-I9195 using Tapatalk Quote Link to comment Share on other sites More sharing options...
Eugene Posted January 29, 2016 Share Posted January 29, 2016 Your best solution is a dedicated plug (red) circuit feeding the inverter (UPS) with dedicated plugs feeding your equipment. No Earth Leakage required. SOLARWIND 1 Quote Link to comment Share on other sites More sharing options...
___ Posted January 29, 2016 Share Posted January 29, 2016 I remember many many years ago when the SANDF was pulling out of Namibia and they sold all that old equipment on auction, a nearby farmer bought an old 3-phase generator on a trailer. He also had a second single-phase generator that would power only one of the phases. He wanted both alternators to charge the batteries though -- both of them had DC generators as well (those lovely old Hoffbergs). So an electrician wired up the 4-wire 3-phase to his circuits, and then I (barely out of high school) got called in to wire up the battery charging. The problem was that with both chargers hooked up (not running, just hooked up), the one breaker would just trip all the time. We eventually tracked it down to the negative side of the generators both being grounded to the negative of the battery bank, and also to the neutral, and back then we fixed it by just removing this and leaving the generator negative floating on the one side...To this day I'm not sure what the problem was there. On the three-phase side the center of the star makes up the neutral on all the phases, and will be grounded, and therefore tied to battery negative. On the other side, the neutral of that alternator would be grounded in the same manner. Somehow... there was enough of a problem to trip a breaker. Anyway, this is off topic, I just though to of it again. Quote Link to comment Share on other sites More sharing options...
superdiy Posted January 29, 2016 Share Posted January 29, 2016 SuperDIY, are these inverters not supposed to be plug an play, when not wired into the DB board? Yes, it is a pretty straight forward connection. If no N-E bonding is in place, you should not have any ELR tripping, unless the inverter is damaged. SOLARWIND 1 Quote Link to comment Share on other sites More sharing options...
Arandoza Posted January 30, 2016 Share Posted January 30, 2016 Hi, Just to add my two cents worth I managed to swap the live and neutral feeding my inverter from Eskom. I initially put a 15a plug on the input and plugged it into an existing wall socket to charge the batteries. Had no problems with tripping, but then started to connect the inverter to its own db board and add lighting first without problem. However as soon as I connected my first plug circuit to the second db and connected something into one of the plugs, it would trip the earth leakage on the first Eskom db and give a nasty flash from the one breaker on the first db. It was all caused by the source power to the inverter having the live and neutral reversed in the 15a plug going into the inverter. As your setup is a mobile setup Maybe check you have not got the same issue? Mine worked ok, with reversed live and neutral. For my lights, Only once I put the a plug circuit did the problem become apparent. Good luck. Quote Link to comment Share on other sites More sharing options...
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