The Solar Combiner Box 2 String is a DC combiner box guarding two PV strings before the inverter. Across South Africa, homeowners, smallholdings and installers use it on small rooftop arrays.
It’s a solar combiner box with breakers, fuses and surge units already fitted. That means less site work and a neater DC side.
Inside The Solar Combiner Box 2 String
The box fits two DC breakers, two DC surge units, four fuse holders and four solar fuses. Separate outputs keep a fault on one string away from the other. Each breaker isolates one string for service while its partner keeps running.
- Two strings in and two protected outputs for clean routing.
- IP65 enclosure suits outdoor mounting near the array.
- MC4 connectors let installers land string cables quickly.
PV Combiner Box 2 In 2 Out
Dual MPPT Inverters
A dual MPPT inverter tracks each string on its own input. Keeping both outputs separate lets each string run at its own best point. That matters when strings face different roof sides or catch shade at different times.
Think of the solar combiner box wiring diagram as a simple line. Each string passes its fuses, breaker and surge unit before reaching its own MPPT input. Keep both string voltages inside the inverter’s MPPT window.
When One Output Works
A 2 in 1 out box joins both strings onto one input. It suits a single MPPT inverter, but both strings then need matching voltage. For a dual MPPT inverter, separate outputs make better use of each tracker.
Inverter And System Compatibility
Check your inverter first, since a PV combiner box 2 in 2 out needs two MPPT inputs. For three or four strings, step up to the 4-string DC combiner box instead. Both sit in our Combiner Box Solar range, and neither suits AC circuits or battery cables.
Best Use Cases For This Box
- Homeowners adding a second string to a hybrid inverter.
- Smallholdings needing an off grid solar combiner box.
- Installers who need string protection before a CoC.
This box suits homeowners tired of callouts from loose roof joins, and installers chasing a clean CoC. Both strings land in one sealed box, so your electrician sees every fuse at a glance. It also suits first-time home installs on a single hybrid inverter.
Warranty Compliance And Trust
SANS 10142-1 and SANS 10142-1-2: PV DC wiring and embedded generation must follow the national wiring code. You need a Certificate of Compliance (CoC) from a registered electrician for the full PV installation.
The enclosure carries an IEC 60529 IP65 rating for outdoor mounting. Grid-tied or hybrid systems must be registered with the municipality or Eskom as SSEG.
Spares include the Fuse Holder, Solar Fuse 25A 1000VDC and DC Surge Protector 500V 2P. Other DC breakers and surge devices sit in our AC and DC protection devices range. Before swapping a fuse, compare the fitted rating with your panels’ maximum series fuse rating. Earth the surge units with the Earth Spike M12 x 12mm 1.2m.
Our solar design and installation team can size the full system for you. Free quotes and site visits are part of that service. Payment is by secure EFT or Visa card.
What Is Included
- Pair of DC breakers.
- Twin DC surge units.
- Four fuse holders with four solar fuses.
- MC4 connectors for both string cables.
Delivery runs nationwide in 2 to 5 working days, with collection points across South Africa. Order the Solar Combiner Box 2 String today and protect both strings properly.
Last Updated: October 2026
