RELIABILITY BEGINSWITH ENGINEERING.
A junction box spends twenty-five years or more on a module roof, through heat, ultraviolet light, rain, frost and continuous electrical stress. Our engineering is organised around the six areas that decide whether it lasts.
Every joint and conductor in the current path adds resistance and heat. We select diodes, terminal metals and cable for low losses at each variant's rated current.
- Diode forward voltage and current rating
- Conductor cross-sections sized for continuous current
- Stable, low-resistance joints
A bypassing diode dissipates heat continuously inside a sealed box on a hot module. Our split design places one diode in each of three boxes, and terminal design spreads heat away from each junction.
- Junction temperature limits at worst-case ambient
- Derating against module short-circuit current
- Heat spreading through terminals and potting
The box must keep water out for decades through rain, condensation and thermal cycling. Each split box is sealed to IP68 with a cover gasket, potting and sealed cable entries.
- Gasket and lid retention under thermal cycling
- Sealing at every cable entry
- Potting coverage of live parts
Housing, insulation and potting materials must hold their electrical and mechanical properties after long exposure to UV, heat and humidity at 1500 V.
- UV and thermal ageing resistance
- Tracking resistance and flammability
- Adhesion to the module surface
The product and its assembly process are designed together, so that every unit is built the same way and inspected at each step.
- Design for fixtured, repeatable assembly
- Error-proofing of polarity and orientation
- Traceability from component lot to finished set
Our junction boxes are built to IEC/EN 62790, with quality checks designed into production and electrical testing at the end of the line.
- Testing aligned to IEC/EN 62790 categories
- End-of-line electrical testing on every unit
- Production quality checks and batch sampling
Electrical performance and component selection
Shade one substring.Keep the rest working.
Crystalline modules are usually wired as three substrings, each protected by its own bypass diode. In a 3-split junction box, each diode sits in its own box. The diagram shows what happens when one substring is shaded.
Three-substring module with a 3-split junction box
Current flows through every cell
In full sun all three substrings generate, and current passes through them in series. Each bypass diode is reverse-biased and carries almost no current.
Switch to a shaded condition to see what the junction box does when part of the module stops producing.
ENGINEERED FROMTHE INSIDE OUT.
Inspect each component of the 3-split box and the engineering behind it.
Talk to us about your module's requirements
Tell us your module format, current and volumes. We will reply with pricing, lead times and the right configuration for your line.