T2 MOV 1P PV Module In=15 kA Imax=40 kA Up1, 9 kV Uc=585 VDC SPV040

Protection of photovoltaic installations against overvoltages

Module SPV040 is designed to protect photovoltaic installations from type‑2 overvoltages, especially those caused by nearby lightning strikes or induced in DC conductors. It functions as a replaceable element in Hager surge‑protective device (SPD) systems, and its construction is optimized for outdoor operation – from ‑40 °C to +80 °C – making it resistant to extreme temperatures on roofs or panels.

The adopted continuous DC working voltage (Uc) of 585 V allows safe use in PV systems with open‑circuit voltages up to approximately 600–700 V, which matches most modern solar modules. The protection level Up of 1.9 kV for all L-N, N-PE and L-PE combinations limits surges to values that do not damage inverters or control electronics – without excessive “clamping” that could unnecessarily reduce efficiency.

The rated discharge current (In) of 15 kA and maximum current (Imax) of 40 kA mean the module can withstand both frequent smaller impulses and rarer, very strong lightning strikes. No additional short‑circuit protection is required – the module itself does not cause a short circuit when it operates, and its short‑circuit withstand capability (Isccr) of 2 kA ensures safety during brief circuit faults.

Installation is performed on a DIN rail – a single module occupies only 17.5 mm of width, allowing compact placement in PV distribution boards. Conductors up to 35 mm² (single‑core) or 25 mm² (flexible) can be connected, covering most standard DC cables in residential and small‑commercial systems. The tightening torque is 3 Nm – a gentle screw press is sufficient without risking contact damage.

Operation indication is optical: a red indicator on the housing clearly signals when the module must be replaced – no multimeter check or system shutdown is needed. The lack of remote‑signal contacts means it cannot be linked to BMS or SCADA systems – but this also results in fewer failure points.

An IP20 protection rating makes the module unsuitable for outdoor mounting – it must be placed inside a closed enclosure. There is no leakage current and no built‑in fuse – it is not a standalone device but a replaceable element in an SPD system.

Compliant with IEC 61643-11 and IEC 61643-15, intended exclusively for DC PV networks. It is not suitable for AC networks or TN-S/TT systems without an appropriate surge‑limiting device.