Wiring two Classic 200's

[charlespyoung]

I am preparing to upgrade an array in Haiti. The current system is a 12 module 3kW array into a Classic 200 feeding 2 strings of Rolls S-550's at 48V. I am doubling the array to a 24 module 6kW array and adding a second Classic 200 . My question is in the best way to wire the two CC's. Should I split the array output into two separate PV output circuits from the combiner box to the two CC's?

[Vic]

Hi Charles,

Yes,  each CC MUST have its own,  separate PV array.

Some of the larger Combiners have easily-separated output busbars,  like the MNPV12,  IIRC  --  it uses two separate busbars that are bolted together for use with single CCs,  or unbolted,  with the bus trimmed a bit,  will feed two separate CCs.

Of course,  CC needs a separate cable from the positive output busbar to the CC.   Some Combiners do not have two negative busbars,  for the PV minus connection.  If this is the case with the Combiner in this system,  then an additional negative PV busbar would need to be added.

Here is some info on the MidNite MNPV12:
http://www.midnitesolar.com/productPhoto.php?product_ID=144&productCatName=Combiners&productCat_ID=9&sortOrder=7&act=p

Since this an addition to an existing system,  the MNPV12 may not have been used,  originally.   But the photo shows a good way of using two separate arrays for two CCs.

Do you know the make and model number of the Combiner on the system?

Vic

[charlespyoung]

Not positive but I think it is a MNPV6.

[Vic]

Hi Charles,

Thanks.   So,  guess that you had planned to add an additional MNPV6,  with its own separate PV positive,  negative,  plus appropriate grounding/bonding cables for the added CC (?).

That should be fine.   Vic

[charlespyoung]

Thanks Vic for your quick responses and great help!!