June 5, 20233 yr 1) If input is at the top, and output at the bottom, then the fuses are in the wrong place. If not, then the breaker is wired backwards and likely to be a fire hazard. 2) Both positive and negative leads need to an isolator (or at least something rated as an isolator). 3) Neither fuse not breaker is marked as being suitable for disconnect under load. The breaker almost certainly is, but without IEC markings, the electrician will probably want to see a datasheet before issuing a CoC.
June 5, 20233 yr Author @Superfly @JustinSchoeman So the PV string positive and negative are coming in to the surge arrestor from the top (from the panels both positive and negative are black cables, this was the first installers work) the top left red cable is the positive going to the invertor. The negative is just joined on the surge arrestor to invertor. The earth wire goes to the panels Edited June 5, 20233 yr by roadkill
June 5, 20233 yr Author @PowerUser Lux sna5000, Max voc on that invertor mppt 480. Voltage range 115-385 or something close to that Edited June 5, 20233 yr by roadkill
June 5, 20233 yr Author @Modina Solar voltage is about 400V, 9x ja 455w panels Edited June 5, 20233 yr by roadkill
June 5, 20233 yr Author @Superflyhow should this have been wired? Where is the spd earth supposed to connect to? He took out my beny 600v dc double pole breaker and put that single five-star in because he said the beny was an AC breaker, I didn't know any better but googled the part and it is a DC breaker. They told me the panels needed an earth wire to the dB board and ran one
June 5, 20233 yr Author @Superfly I wasn't quite happy with the install, so trying to figure out everything that is not complaint so I can take it up with them
June 5, 20233 yr Author @Superfly he removed this breaker because he said it was an AC breaker not a DC
June 5, 20233 yr Author @Superfly Ah thanks that makes sense, so my PV is single string so about 9.45 imp and 10.85 isc, these fuses in the db are 32a but not sure if they are the right fuses? So DC breaker of about 15-20a be fine with 600v rating? Depending on what comes in those sizes I need to check what's available, that way it trips before fuses pop Something like this:? https://www.solar-europe.co.za/product/etek-dc-2p-mini-circuit-breaker-20a-6ka-500vdc-ekm1-63dc-220/ Edited June 5, 20233 yr by roadkill
June 6, 20233 yr 10 hours ago, roadkill said: he removed this breaker because he said it was an AC breaker not a DC Find a decent electrician before this one kills you. That Beny was fine - what he installed is a fire waiting to happen.
June 6, 20233 yr 11 hours ago, Superfly said: OK Cool - keep in touch... Yep you have a 63A DC breaker... not ideal for lower PV amps but does a job as an isolator (I would prefer an MCB rated at the fuse level that would trip before the fuse blows but that's just redundancy) ... anyway.. all the best Why would you install a fuse and MCB breaker rated similar? There is no such requirement. And it’s a waste of money. You have to install either one or the other. Edited June 6, 20233 yr by PowerUser
June 6, 20233 yr 1 hour ago, PowerUser said: Why would you install a fuse and MCB breaker rated similar? There is no such requirement. And it’s a waste of money. You have to install either one or the other. Well, the fuse holder is not rated for disconnect under load, and the breaker has too high a current rating for the wire. So there is some sort of logic to it... But really - one correctly rated 2 pole breaker is what you want. (Or one 2 pole fuse holder, which is rated for disconnect under load.)
June 6, 20233 yr Just now, JustinSchoeman said: Well, the fuse holder is not rated for disconnect under load, and the breaker has too high a current rating for the wire. So there is some sort of logic to it... But really - one correctly rated 2 pole breaker is what you want. (Or one 2 pole fuse holder, which is rated for disconnect under load.) That's why you have an isolator, which is rated to be disconnected under load.
June 6, 20233 yr 13 hours ago, roadkill said: @Superfly they coming to drop off the coc for this job this week That is the problem right there after completion of the installation the COC should be issued after all tests have been concluded. The COC should be accompanied by a test report. When was this install completed? What if there was a fire or somebody electrocuted and you where not in possession of a valid COC before it is dropped off. Wrong and suspect. When they drop of the COC insist you want a copy of the test report.
June 6, 20233 yr Author @TaliaB they dropped off the coc today, I also organised for an electrician to come around to check for me but he didn't pitch. The install was gone 2.5 weeks ago. Ideally just 1 correctly rated breaker would be better for me as I plan to put 3 strings in that dB box and with fused as well as SPD it won't all fit
June 12, 20233 yr Can I jump in and ask a 'similar type of question' ? I recently had an electrician come and finish my solar job (previous electrician vanished when it came to delivering the CoC). The new electrician modified and installed a few extra bits, one of which was this SPD on the DC (solar) side - BY7-18/1+1_ONESTO A few days in to it, my inverter started making some strange noises with the PV voltages jumping all over the place, then eventually, the MPPT 'died', and I noticed the 'green' indicator on the SPD was now red (so assuming the SPD went pop). Is this the correct type SPD? Is it even DC as I have my doubts (as they installed the same one on my AC DB). My solar panels 'used to' supply between 180V - 200V DC and the inverter can handle MPPT Range @ Operating Voltage 120VDC~430VDC (Maximum PV Array Open Circuit Voltage 500VDC) Feedback from some experts really appreciated!
June 12, 20233 yr 1 hour ago, eHunterADJ said: Is this the correct type SPD? Is it even DC as I have my doubts (as they installed the same one on my AC DB). It is not DC rated, but most AC SPDs are safe to run on DC (should have a trip voltage of around 400V DC). Given that it failed, there is a fair chance that this one is not suitable for DC use though. Also, those fuse holders are not rated to disconnect under load, so you should technically have an isolator switch in there too. EDIT: To add - even though many AC SPDs are actually DC capable, it is never a good idea to use one on DC unless it is explicitly DC rated. Edited June 12, 20233 yr by JustinSchoeman
June 12, 20233 yr 1 hour ago, eHunterADJ said: Is this the correct type SPD? If you have the CoC then the best SPD is no SPD. Put a new one in the place of the one that failed but disconnect it.
June 12, 20233 yr 19 minutes ago, frivan said: If you have the CoC then the best SPD is no SPD. Put a new one in the place of the one that failed but disconnect it. They are actually there for a reason not for window dressing @frivan Use DC rated spd's and replace the blown one with dc rated spd see specs below. Edited June 12, 20233 yr by TaliaB
June 12, 20233 yr 2 hours ago, eHunterADJ said: Can I jump in and ask a 'similar type of question' ? I recently had an electrician come and finish my solar job (previous electrician vanished when it came to delivering the CoC). The new electrician modified and installed a few extra bits, one of which was this SPD on the DC (solar) side - BY7-18/1+1_ONESTO A few days in to it, my inverter started making some strange noises with the PV voltages jumping all over the place, then eventually, the MPPT 'died', and I noticed the 'green' indicator on the SPD was now red (so assuming the SPD went pop). Is this the correct type SPD? Is it even DC as I have my doubts (as they installed the same one on my AC DB). My solar panels 'used to' supply between 180V - 200V DC and the inverter can handle MPPT Range @ Operating Voltage 120VDC~430VDC (Maximum PV Array Open Circuit Voltage 500VDC) Feedback from some experts really appreciated!
June 12, 20233 yr 2 hours ago, eHunterADJ said: Can I jump in and ask a 'similar type of question' ? I recently had an electrician come and finish my solar job (previous electrician vanished when it came to delivering the CoC). The new electrician modified and installed a few extra bits, one of which was this SPD on the DC (solar) side - BY7-18/1+1_ONESTO A few days in to it, my inverter started making some strange noises with the PV voltages jumping all over the place, then eventually, the MPPT 'died', and I noticed the 'green' indicator on the SPD was now red (so assuming the SPD went pop). Is this the correct type SPD? Is it even DC as I have my doubts (as they installed the same one on my AC DB). My solar panels 'used to' supply between 180V - 200V DC and the inverter can handle MPPT Range @ Operating Voltage 120VDC~430VDC (Maximum PV Array Open Circuit Voltage 500VDC) Feedback from some experts really appreciated! Your SPD were AC. A DC unit will clearly show the voltage as per this pic.
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