General
Number of poles	4
Lightning impulse current (10/350 µs)	7.5 kA
Max. continuous voltage AC	255 V
Nominal voltage AC	400 V
Max. PV-voltage	0 V
Voltage protection level	1.5 kV
Voltage protection level L-N	1.5 kV
Voltage protection level L-PE	1.5 kV
Voltage protection level N-PE	1.5 kV
Follow current extinguishing capability	25 kA
Specific energy (W/R)	15 kJ/Ohm
Max. conductor cross section solid (solid, stranded)	50 mm²
Max. conductor cross section flexible (fine-strand)	35 mm²
Mounting method	Busbar
Construction size	4 modular spacing
Signalling at the device	Optic
Test class	Type 1
Degree of protection (IP)	IP20
System configuration DC
System configuration IT
System configuration TN
System configuration TN-C
System configuration TN-C-S
System configuration TN-S
System configuration TT
System configuration other
Remote signalling
Integrated backup fuse
Energy-coordinated protection effect with regard to the terminal equipment

The Hager surge protection device SPA701Z is a type T1+T2+T3 device with 4 poles, specifically designed for TT and TN-S network configurations. It provides protection for electrical installations against direct lightning strikes and transient overvoltages, particularly in power engineering applications. The device features a lightning impulse current rating (Iimp) of 7.5 kA and is designed for mounting on a busbar. The IP20 protection rating ensures protection against finger contact and solid foreign objects, but not against water or dust—making it suitable for indoor installations.

Applications

The SPA701Z is intended for use in electrical installations with a nominal voltage up to 400 V AC and a continuous voltage up to 255 V AC. It is particularly suitable for installations operating in TT or TN-S network configurations, as commonly found in industrial and commercial buildings as well as power supply systems. The combination of Type 1 and Type 2 protection enables comprehensive safeguarding against high-energy impulses and smaller overvoltages originating from the network or internal switching operations.

Functions and Features in Detail

The device offers a protection level of 1.5 kV for all pole combinations (L-N, L-PE, N-PE), ensuring effective limitation of overvoltage peaks. The follow current interruption capacity is 25 kA, meaning the device can safely disconnect the circuit after an overvoltage impulse without posing a risk of subsequent short-circuit current endangering the installation. The specific energy (W/R) of 15 kJ/Ohm indicates the device’s capability to dissipate high energy levels. Status indication is provided optically via an indicator light, which shows the operational state. Remote signalling is not integrated.

Technical Explanation

The surge protection device operates on the principle of diverting overvoltages through a discharge resistor or capacitor to earth. During an overvoltage impulse, such as a lightning strike, the current is diverted through the device, thereby protecting connected equipment. The Type 1 test class means the device is designed for direct lightning strikes, while the Type 2 function handles overvoltages from the network or internal switching operations. The energy-coordinated protective effect with the downstream device ensures that the surge protection and the downstream fuse work harmoniously to enable selective disconnection.

Compatibility and Accessories

The device is designed for mounting on a busbar and fits into a mounting size of 4 TE. It is compatible with TT and TN-S network configurations. As an accessory, the remote signalling contact SPA078R is available and can be optionally connected to monitor the status of the surge protection device via a remote signalling system.

Mounting and Installation

Mounting is performed on a busbar, with a nominal torque of 2.5 Nm specified for the screw connections. The maximum conductor cross-sections are 50 mm² for rigid and 35 mm² for flexible conductors. Connections are made via screw terminals, with acceptable cross-sections ranging from 2.5 mm² to 50 mm² (rigid) or 35 mm² (flexible). The operating temperature range of the device is from -40 °C to +80 °C, enabling use in various environments.

Operational Advantages

The SPA701Z provides robust and reliable protection for electrical installations. The combination of Type 1 and Type 2 protection in a single device reduces the number of required components and simplifies installation. The optical indication allows for quick visual inspection of the operational status. The halogen-free and RoHS-compliant design meets current environmental standards. The integrated coordination with downstream fuses ensures selective disconnection, limiting the disturbance and preventing the entire installation from being shut down.