826v DC Isolator??

[Mark Davey]

I am completing a 9.87kWp install using 42 235W modules and a PowerOne 10.0-OUTD 3phase inverter, the PowerOne design tool recommended 2 strings of 21 modules however the string voltage is 826v and I cannot seem to find a DC isolator capable of greater than 800v.

Any recommendations or advise would be much appreciated?

 

[moggy1968]

Why not come off the panels as 4 strings, then use MC4 combiners to put them into 2 strings (by connecting in parallel). That will reduce your voltage to 413v and double your current

 

[SibertSolar]

1000VDC rated DC isolator isn't a problem, pm me your number if you want and I'll call you to discuss options

 

[daytona600]

1000vdc v isolators are very common biggest are 800kvdc

 

[mr murdock]

true "SNAP ACTION" 1000V DC isolators are not that common, I can only think of two true 1000V DC Isolator brands in the UK - this is one of them - I have seen the spec sheets for many brands that claim to be suitable for DC application, most (even big well known names) are not suitable for DC application at 1000V 16A but have still been installed all over the country... I have often wondered how many of the AC isolators that were used for DC application during the PV installation boom will need to be replaced and weather some one will have to die before this issue is addressed...

 

[Glen Powell]

Most small enclosure true DC isolators are max 800v at 16 amps may be worth going 600v at 32amps and change config of panels.

but this is an old post and probably flogged to death.

 

[SibertSolar]

Completely agree with your sentiment but, with all due respect, that Europa unit has a benedikt contact block inside it, as do the IMO units. Excellent products both because of that fact alone. 1000vdc ratings at the full contact current rating (16, 25 & 32A) is achievable by using the linking bars as per the tech specs although you do then "lose" a pair of poles in the 4-pole version. Santon have an equally high quality design, although they do offer a 4-pole switch that can disconnect 2 strings at 1000vdc (16 or 25A) each.

Some, inferior, "multi-pole" switches struggle to achieve 650vdc ratings even after series linking poles together....

As for how many "false" DC disconnectors are out there already, thousands upon thousands....but then I'm guilty of banging a drum about this for some time (although I do accept that it is a complex subject that has to be looked at from more than one angle)