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Discuss Solar panel circuit MCB size? in the Solar PV Forum | Solar Panels Forum area at ElectriciansForums.net
i thought some of the fronius inverters came with a 15 year guarantee?same as isis solar and home sun apart from a lot of these were fitted with fronius inverters.
I know, but the rate of cooling is directly proportional to the ambient air temperature.dont forget that is internal temperature and the internals will hit 30oC quite easily inside the inverter so i doubt it would make a huge difference, throw as many charts at me as you like
i thought some of the fronius inverters came with a 15 year guarantee?
i thought some of the fronius inverters came with a 15 year guarantee?
Fronius offers a 5-year manufacturer warranty on all inverters as standard. You also have the option of extending the warranty period to 10, 15 or 20 years. If a claim is made, Fronius bears the costs for original replacement parts, transportation and work undertaken. The extended warranty therefore protects against any fluctuations in price for the entire warranty period. In addition, free support is on hand from our competent and easy to reach hotline team for the entire duration of the warranty period.
dont forget that is internal temperature and the internals will hit 30oC quite easily inside the inverter so i doubt it would make a huge difference, throw as many charts at me as you like
what are you talking about?i understand your point on mechanical protection. but you keep banging on about start up insulation tests etc,this is irrelevant as the dc cables will still be live before, during and after regardless if the inverter starts up or not due to the insulation resistance test carried out by the inverter
what are you talking about?
the panels themselfs are always generating electricity the inverter only checks for supply on ac and switches dc accordingly
ah i didnt see a quoteim quoting Gavin A
ah i didnt see a quote
not irrelevant as if the inverter doesn't start up, or cuts out, then even on a TL inverter the circuit stays / becomes an electrically separated circuit with no potential to earth, so even if the cables did somehow get damaged and exposed despite the mechanical protection it would only be dangerous if someone actually grabbed hold of both + and - exposed cables at the same time, and only life threatening if they were holding one bare wire in each hand. ie they could touch the positive or negative cable while also touching an earth bonded radiator and feel absolutely nothing.i understand your point on mechanical protection. but you keep banging on about start up insulation tests etc,this is irrelevant as the dc cables will still be live before, during and after regardless if the inverter starts up or not due to the insulation resistance test carried out by the inverter
no it doesn't require an RCD.Yes solar PV should be protected by an RCD. Some manufacturers state 30Ma some state 100Ma. The solar array is outside, usually roof mounted so it requires RCD protection. I always install a new 2 way RCD board separate from the domestic CU to avoid nuisance tripping. The PV installation can have quite a lot of earth leakage and if it's connected to the same RCD as the house it can cause problems. Separating the two installations can make life a lot easier with regard to nuisance tripping.
Thanks Gavin, To comply with BS7671 though, if the solar panel circuit is wired pvc t+e cable and buried within the plasterwork (less than 50mm) it must be protected by a 30Ma RCD. As far as I can see, no choice in the matter. Are ALL your LV circuits wired on the surface? Thanksno it doesn't require an RCD.
The inverter manufacturers give specifications for RCD fitting where required by local regulations - ie where required by BS7671, so an RCD is only needed where it's required under BS7671.
All you're doing is adding a source of nuisance tripping to the system by adding an RCD where it's not needed.
Thanks Rico, what I was planning was that the Solar panel circuit be wired on its own RCBO circuit, which is basically what you have been doing. I'm not into solar panel wiring, this is just a one off. Why do you install a 2 way unit? ThanksYes solar PV should be protected by an RCD. Some manufacturers state 30Ma some state 100Ma. The solar array is outside, usually roof mounted so it requires RCD protection. I always install a new 2 way RCD board separate from the domestic CU to avoid nuisance tripping. The PV installation can have quite a lot of earth leakage and if it's connected to the same RCD as the house it can cause problems. Separating the two installations can make life a lot easier with regard to nuisance tripping.
Yes, I understand your thinking hence I've gone separate RCBO's for each circuit. Just wondering why you put a 2 way unit in. Do you mean that the RCD + MCB takes the 2 ways up? Or you require 2 x circuits for your systems?I install a 2 way board for the PV so the combined earth leakage from the house and PV doesn't cause problems. I cut the tails and put Henley blocks on them. This way my house CU and PV CU are separate. So the earth leakage from the house and PV doesn't combine to trip RCD's. The PV earth leakage can be quite high so i tend to put that on its own RCD as recommended in the manufactures instructions. I have been called out to lots of installations that are tripping because they have not been installed this way. I change it to this method and all is solved. Easier for testing too.
I think you'll find that the outside bit is DC, and your RCD has nothing to do with that side of the inverter - the RCD wouldn't trip if there were a fault on the DC circuit, how could it?I think you will find outside is a special location that requires RCD protection. All manufactures instructions on systems I have fitted have stated it requires RCD protection. Also I said I install a seperate board for PV with its own RCD, to prevent nuisance tripping on the domestic circuits. The MCS guy also confirmed that a RCD is a requirement on my annual inspections
or use earthed metal capping, but yes an RCD would be one way of protecting the circuit in that situation.Thanks Gavin, To comply with BS7671 though, if the solar panel circuit is wired pvc t+e cable and buried within the plasterwork (less than 50mm) it must be protected by a 30Ma RCD. As far as I can see, no choice in the matter. Are ALL your LV circuits wired on the surface? Thanks
I think you will find outside is a special location that requires RCD protection.
yup, ive seen 700v on some strings on bigger solar panel jobs.I think you'll find that the outside bit is DC, and your RCD has nothing to do with that side of the inverter - the RCD wouldn't trip if there were a fault on the DC circuit, how could it?
The inverters are either galvanically isolated, or transformerless with an integral RCMU unit to protect them.
what the MCS guy said says more about the substandard nature of the MCS inspection system than it does the reality of what's required.
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