Weidmüller, a German company that specializes in electrical connectivity solutions, promoted its latest compact PV combiner box, PV Inline, at Intersolar Europe 2025. Designed to protect small rooftop PV installations in Europe from external overvoltages, the company briefly spoke about this innovative surge protection device to the TaiyangNews team at its booth.
This product series consists of 2 different models – PVI DC 1I 1O 1MPP SPD1 MC4 10 and PVI DC 1I 1O 2MPP SPD1 MC4 10.
Product Description
Both models are well-suited for small rooftop systems with limited installation space. Each unit is equipped with Type I and Type II surge protection devices (SPDs) that protect against overvoltages, including lightning-induced surges, by safely diverting excess energy to ground.
Both versions support a rated DC voltage of up to 1,100 V. The 1MPP model supports one MPPT channel with a single string input, capable of carrying up to 39 A. The 2MPP model accommodates 2 MPPT channels, each with a single string input and a maximum current capacity of 39 A.
According to the company’s datasheet, this compact combiner box does not use any fuse cartridges or holders. It integrates with both positive and negative DC PV cables ranging from 4 mm² to 6 mm² in cross-sectional area and is fitted with Stäubli MC4 connectors. Each cable pair (positive and negative) corresponds to a separate MPPT channel.
A 16 mm² pre-assembled functional earth cable is included, serving as a critical safety feature. Notably, aside from the absence of this functional earth connection, the DC output connection per MPPT channel is identical to its input connection, maintaining a streamlined design.
The integrated SPD, with a maximum continuous operating voltage (DC) of 1,100 V, has a nominal discharge current rating of up to 20 kA, while the maximum rated discharge current is up to 40 kA, providing protection under severe surge conditions.
Flexibility In Installation
This compact safety device can be installed in diverse space-confined scenarios, including mounting on or in between a cable duct, wall mounting, or mounting behind a PV module.
The company says PV Inline can be easily installed on a standard 60 × 40 mm cable tray using dedicated mounting accessories or positioned precisely between 2 trays, allowing the compact surge protection device to visually integrate with the cable routing system. Due to its compact design, this device can also be mounted behind a PV module using UV-resistant cable ties, adds Weidmüller. This offers a practical advantage for large-scale installations where the distance between the inverter and PV modules exceeds 10 meters.
The company offers a 5-year guarantee for this device.
