Slaaiblaar Posted September 7, 2021 Share Posted September 7, 2021 I'm building a combiner box and nee info 1. fuse only on pos incoming from PV or pos and neg? 2. Which surge protector? 3. Double pole isolator required? Quote Link to comment Share on other sites More sharing options...
De0n19 Posted September 8, 2021 Share Posted September 8, 2021 1)I would also like to know the proper placement and quantity of the fuse as normally you would place a fuse at the power source, so to me the best place is at the panels so that if a short occurs on the cable the fuse has a chance to blow and protect the cable from burning. 2) you would need to look at the voltage that your panels would produce in winter and the max voltage of your mppt. The surge protection should be between those two ratings but closer to the mppt max voltage should be best. 3) double pole isolater is a must Slaaiblaar 1 Quote Link to comment Share on other sites More sharing options...
[email protected] Posted September 9, 2021 Share Posted September 9, 2021 (edited) This is what I do, have done the PV Green Card Installation Course. This is what is recommended. A fuse on the Positive and Negative legs, a surge protector and a Double Pole Isolator switch. See drawings below. No fuses on the roof, only connectors where you can disconnect if needed. If you disconnect make sure the fuse on bottom panel are disconnected as it can cause big spark. Earth the Solar panel structure and connect to a separate earth Pin, 1.5mters so that lighting would be taken direct to ground and not to Electrical Earth. I ordered all component's from Solar Europe in Pretoria. Solar Europe - Solar Energy Brands Importer and Distributor (solar-europe.co.za) 07 Panel PV Isolation Layout.pdf 08 Panel PV Isolation Layout.pdf Edited September 9, 2021 by [email protected] Gerrie 1 Quote Link to comment Share on other sites More sharing options...
Tariq Posted September 9, 2021 Share Posted September 9, 2021 the Sunsynk inverter has a built in idolater for the two mppt's, will that suffice or do you need another one in the combiner box Quote Link to comment Share on other sites More sharing options...
Leshen Posted September 9, 2021 Share Posted September 9, 2021 9 hours ago, Tariq said: the Sunsynk inverter has a built in idolater for the two mppt's, will that suffice or do you need another one in the combiner box Hi Tariq. I use the fuses that also doubles up as an isolator. You will need some sort of isolator in a combiner box. Quote Link to comment Share on other sites More sharing options...
gooseberry Posted September 9, 2021 Share Posted September 9, 2021 2 hours ago, Leshen said: Hi Tariq. I use the fuses that also doubles up as an isolator. You will need some sort of isolator in a combiner box. Those fuses you can't disconnect under load though right? Quote Link to comment Share on other sites More sharing options...
Leshen Posted September 9, 2021 Share Posted September 9, 2021 1 minute ago, gooseberry said: Those fuses you can't disconnect under load though right? You should never disconnect any DC breaker under load hoohloc 1 Quote Link to comment Share on other sites More sharing options...
gooseberry Posted September 9, 2021 Share Posted September 9, 2021 Just now, Leshen said: You should never disconnect any DC breaker under load but that is what specialised DC breakers are made for... like the Noark ones. Of course you avoid it if you can. Quote Link to comment Share on other sites More sharing options...
Leshen Posted September 9, 2021 Share Posted September 9, 2021 9 minutes ago, gooseberry said: but that is what specialised DC breakers are made for... like the Noark ones. Of course you avoid it if you can. Yes it is however it’s poor practice to disconnect PV under load. You can cause permanent damage to some inverters. The hazard and warning labels we stick specifically state, DO NOT DISCONNECT UNDER LOAD. Yellow Measure 1 Quote Link to comment Share on other sites More sharing options...
Tariq Posted September 10, 2021 Share Posted September 10, 2021 13 hours ago, Leshen said: Hi Tariq. I use the fuses that also doubles up as an isolator. You will need some sort of isolator in a combiner box. @Leshen, yes, I do use the same quick disconnect fuses in the combiner box, also, if i have to do any panel wiring work, i first switch off the isolator on the Sunsynk and then disconnect the fuses. However my question was, is an isolator needed in the combiner box as per regulations Quote Link to comment Share on other sites More sharing options...
Leshen Posted September 10, 2021 Share Posted September 10, 2021 1 hour ago, Tariq said: @Leshen, yes, I do use the same quick disconnect fuses in the combiner box, also, if i have to do any panel wiring work, i first switch off the isolator on the Sunsynk and then disconnect the fuses. However my question was, is an isolator needed in the combiner box as per regulations Hi Tariq. Are these COCT regs? Quote Link to comment Share on other sites More sharing options...
Tariq Posted September 10, 2021 Share Posted September 10, 2021 Don't think CoCT has these kind of regulations, was asking if SANS requires an isolater Quote Link to comment Share on other sites More sharing options...
Leshen Posted September 10, 2021 Share Posted September 10, 2021 5 minutes ago, Tariq said: Don't think CoCT has these kind of regulations, was asking if SANS requires an isolater There is no legislated SANS regs on Solar PV installations. Yellow Measure 1 Quote Link to comment Share on other sites More sharing options...
shovelhead Posted September 10, 2021 Share Posted September 10, 2021 17 minutes ago, Leshen said: There is no legislated SANS regs on Solar PV installations. This is interesting as CoCT require a "DC COC" which I assume to cover PV and battery wiring. Any ideas on what this COC should cover then if there are no regs? Quote Link to comment Share on other sites More sharing options...
Leshen Posted September 10, 2021 Share Posted September 10, 2021 18 minutes ago, shovelhead said: This is interesting as CoCT require a "DC COC" which I assume to cover PV and battery wiring. Any ideas on what this COC should cover then if there are no regs? That’s the reason I asked if it’s a COCT regulation. Currently SANS 10142 doesn’t cover Solar. If someone can show me the SANS regs which covers Solar then I stand corrected. hoohloc and Yellow Measure 2 Quote Link to comment Share on other sites More sharing options...
Tariq Posted September 10, 2021 Share Posted September 10, 2021 when submitting your application to CoCT, you have to include a diagram of the solar installation which includes the integration with the main db and grid, the coc that i sent in did not have too much detail on the solar installation. Below is what I received from a forum member PV-System-Interim-Guidelines-Good-Practice-for-Solar-PV-Installations-South-Africa- (002).pdf Quote Link to comment Share on other sites More sharing options...
shovelhead Posted September 10, 2021 Share Posted September 10, 2021 12 minutes ago, Tariq said: when submitting your application to CoCT, you have to include a diagram of the solar installation which includes the integration with the main db and grid, the coc that i sent in did not have too much detail on the solar installation. Below is what I received from a forum member PV-System-Interim-Guidelines-Good-Practice-for-Solar-PV-Installations-South-Africa- (002).pdf 1.07 MB · 2 downloads @Tariq could you please share the detail of the solar installation coc that was included? I am currently stuck at this point as my installation was done in 2015 prior to all these requirements. Quote Link to comment Share on other sites More sharing options...
PowerUser Posted September 10, 2021 Share Posted September 10, 2021 @Tariq and @Leshen, if it helps to clarify, I have a copy of a draft standard from 2020 which explicitly requires a disconnector. However, I don't know, if that draft has been enforced into law by now: Quote Link to comment Share on other sites More sharing options...
Tariq Posted September 10, 2021 Share Posted September 10, 2021 @shovelhead, pm me and I’ll try to help you out Quote Link to comment Share on other sites More sharing options...
randomwalsh Posted February 4, 2023 Share Posted February 4, 2023 On 2021/09/09 at 7:53 AM, [email protected] said: This is what I do, have done the PV Green Card Installation Course. This is what is recommended. A fuse on the Positive and Negative legs, a surge protector and a Double Pole Isolator switch. See drawings below. No fuses on the roof, only connectors where you can disconnect if needed. If you disconnect make sure the fuse on bottom panel are disconnected as it can cause big spark. Earth the Solar panel structure and connect to a separate earth Pin, 1.5mters so that lighting would be taken direct to ground and not to Electrical Earth. I ordered all component's from Solar Europe in Pretoria. Solar Europe - Solar Energy Brands Importer and Distributor (solar-europe.co.za) 07 Panel PV Isolation Layout.pdf 37 kB · 60 downloads 08 Panel PV Isolation Layout.pdf 30.15 kB · 57 downloads Hey. I have question about why in your diagram you have a positive going into pole 1 on the beny isolator and then coming out on pole 6. Is that how those beny isolators work? They aren't straight channels? Quote Link to comment Share on other sites More sharing options...
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