Surge protective device ESPPV V T12 12,5/1000 Y 20121003080

Photovoltaic Lightning Protection - Monobloc Surge Protector

ESPPV V T12 series surge protectors are designed to protect photovoltaic installations from the effects of direct and indirect lightning strikes. They prove effective in situations where the building is equipped with an LPS (lightning protection system), but the separating distances for PV panels have not been maintained - meaning the risk of sparkover to the modules is real.

The device operates in an IT network system, which is the standard in photovoltaics - the panel strings are not grounded on the negative side, but connected to the inverter in a unipolar configuration. This distinguishes them from typical AC installations and requires a dedicated DC surge protector.

Monobloc Design and Status Indication

ESPPV V T12 is constructed as a monobloc - all protective elements are integrated into a single housing, without replaceable modules. This solution increases the mechanical strength of the device and eliminates the risk of incorrectly mounting components in the wrong order during servicing.

On the front of the housing there is an optical indicator showing the current status of the device:

• Green - device operational, protection active,
• Red - module replacement required (device has tripped and no longer provides full protection).

This allows the surge protector status to be assessed at a glance, without the need to disassemble the installation or use measuring tools.

Protective Parameters and Energy Absorption Capacity

The device is classified as Type 1+2, meaning it is capable of operating with impulse currents generated by both direct lightning strikes on the structure (10/350 µs) and indirect induced overvoltages (8/20 µs). These parameters are respectively:

• Impulse current Iimp (10/350): 12.5 kA,
• Nominal current In (8/20): 20 kA,
• Specific energy W/R: 39.1 kJ/Ω.

This combination allows it to handle short-circuit lightning impulses from direct strikes on the LPS, as well as multiple atmospheric overvoltages from nearby discharges.

Both DC+ and DC- paths, as well as the insulation between poles and ground, are protected at 3.8 kV - which is significant at string operating voltages reaching hundreds of volts. The maximum continuous DC working voltage is 1050 V. When selecting, the installer should verify the condition UCPV ≥ 1.2 × UOC STC - meaning the continuous voltage must be at least 20% higher than the open-circuit voltage measured under standard test conditions for the panels.

DIN Rail Mounting and Electrical Compatibility

The surge protector occupies 4 modules on a TH-35 mm rail (installation width 72 mm). Installation is possible in two mounting positions on the rail - which facilitates fitting to existing distribution boards even with tight wiring layouts.

In terms of wire connection, the device supports:

• Single- and multi-wire conductors up to 50 mm²,
• Flexible conductors up to 35 mm².

The enclosure protection rating is IP20, but the manufacturer permits outdoor use - which is important when mounting directly at the inverter or photovoltaic distribution board on the facade. In such cases, it is essential to provide an additional enclosure with a higher IP rating or place the device in an outdoor cabinet.

The absence of a remote signaling contact means that status monitoring of the device is performed exclusively through the optical indicator - the installer or user must physically look into the distribution board. If remote signaling is required (e.g., integration with a BMS system), a model with a dedicated alarm contact or an external monitoring module connected to the auxiliary circuit should be considered.