When I'm wiring the panels in multiple strings do I just move the wires to the correct terminals to get the series connections. Also do I connect them into a main home run wire to the combiner box or does the positive and negative from each string go to the combiner box? Thanks for the help with this.

Comments

This question refers to the building of a parallel module string, from series string designed modules. In the past, battery based system were designed around the 12v battery and the 12v PV module. The charge controller could accomplish its task simply by modulating voltage fairly tightly around the 12v mark.  Now, there is a huge selection of PV modules in voltages ranging to 100v per module. System designers are also realizing the benefits of transporting power from the array to the controller at a relatively high value to decrease amperage and wire size.

Most modules above a nominal 24v come with some kind of factory installed locking, weathertight connector, commonly called an MC connector after the company named Multi-Contact, which popularized them. The connectors are a male/female pair which allow them to be connected to adjacent modules only as a series string - the integral input to a grid-tied inverter of 96% efficiency being a DC voltage above 200v.

Many new MPPT battery charge controllers are capable of accepting input voltages of up to 150vdc. But it's still common to use 24v modules in parallel for the 24v-48v max input controllers. So, how to wire them?

Cutting the ends off the module leads may or may not void the warrantee of the module.

The options are:

1. Buy Parallel Y Adapters in the correct configuration

Our part listing: https://www.greentechrenewables.com/product/multi-contact-mc-13?qty=1

2. Make or buy extension wires to run to the nearest combiner box. By fabricating your own, or buy one that's twice the length, and cut it in half, using the cut end in the combiner box.

Our part listing:https://www.greentechrenewables.com/product/multi-contact-mc-6

File Attachment(s)
View
35.jpeg2.43 KB
View
37.jpeg4.29 KB
Submitted
14 years 3 months ago
Asked by
Michael Goldberg