GBV-120-385-3+1-FM AC Power Surge Protective Device, 3+1 Configuration, 120kA Imax

Description

The GBV-120-385-3+1-FM is a 3+1 configuration surge protective device in the GBV-120 series, intended for first-level (Class B) lightning and surge protection of load equipment on AC power systems. It limits transient overvoltages on the protected line and indicates its own status through a colour-changing window.

Product Overview

The GBV-120 series is used for first-level (Class B) lightning protection and surge protection of load equipment in power systems. The GBV-120-385-3+1-FM variant uses a 3+1 pole configuration with a Uc of 385 V on the phase-to-neutral path and a separate N-PE path rated at 255 V. It is designed to be installed in parallel with the power line, either in LPZ0B zones or directly inside distribution cabinets and switch boxes.

Key Features

• 3+1 configuration for AC power system protection
• Nominal discharge current In 60 kA and maximum discharge current Imax 120 kA, both at 8/20 µs
• Voltage protection level Up 3.0 kV at In (L-N) and 2.0 kV at In (N-PE)
• Fast response: tA ≤ 25 ns (L-N) and ≤ 100 ns (N-PE)
• Status window: white indicates normal operation, red indicates failure
• Optional remote signalling via alarm dry contact, NC-COM normally closed
• 35 mm electrical DIN rail mounting
• Housing material: reinforced thermoplastic, UL94-V0

Technical Specifications

Parameter	Value
Model	GBV-120/385/3+1 FM
Maximum continuous operating voltage Uc	385 V
Nominal discharge current (8/20 µs) In	60 kA
Maximum discharge current (8/20 µs) Imax	120 kA
Voltage protection level (In) Up	3.0 kV
Response time tA (L-N)	≤ 25 ns
Response time tA (N-PE)	≤ 100 ns
N-PE maximum continuous operating voltage Uc	255 V
N-PE voltage protection level (In) Up	2.0 kV
Failure indication	White: normal; red: failed
Remote signalling (optional)	Alarm dry contact NC-COM: normally closed
Backup fuse	125A gl/gG
Temperature range	-40 °C … +80 °C
Installation wiring method / specification	Parallel / stranded 25–50 mm²
Housing material	Reinforced thermoplastic, UL94-V0
Product dimensions	91 × 65.5 × 108 mm
Mounting method	35 mm electrical DIN rail
Protection rating	IP20

Applications

The GBV-120-385-3+1-FM is used for first-level (Class B) lightning protection and surge protection of load equipment in power systems. It can be installed in LPZ0B zones or directly in distribution cabinets and switch boxes, protecting equipment connected downstream on the AC supply.

Installation and Use

• Inspect the surge protective device before installation. Do not install a device that shows any defect.
• Use the device only within the conditions stated in its technical table. Exceeding the given upper limits may damage the surge protective device or the protected equipment.
• Installation must follow the relevant standards and codes for the device and must be carried out by qualified personnel in front of the electronic equipment to be protected.
• The device can be installed in LPZ0B zones or directly in distribution cabinets (switch boxes).
• It can be fixed on a 35 mm electrical DIN rail.
• Connect the surge protective device in parallel to the power line: “L/+” to the phase line or positive line, “N/-” to the neutral line or negative line. The copper conductor cross-section at both ends is 25–50 mm².
• An overcurrent protection device such as an air switch or fuse must be installed ahead of the surge protective device in the circuit.
• Connect the ground with the shortest possible cable. The device uses terminal grounding: the “PE” ground wire must be connected to the lightning protection ground.
• Keep the protected line at a sufficient safe distance from the incoming line and ground line to avoid secondary induction.
• Under conditions not exceeding the specified requirements, the device does not require long-term maintenance; only routine system maintenance is needed. If the white indicator window turns red during use, the surge protective device is damaged and must be repaired or replaced.

Frequently Asked Questions

What does the status window indicate?

A white window indicates normal operation. A red window indicates that the surge protective device has failed and needs repair or replacement.

How is the device connected?

It is connected in parallel to the power line. “L/+” connects to the phase or positive line, and “N/-” connects to the neutral or negative line, using stranded copper conductors of 25–50 mm².

What overcurrent protection is required ahead of the device?

An air switch or fuse must be installed ahead of the surge protective device. The specified backup fuse is 125A gl/gG.

What is the mounting method?

The device mounts on a 35 mm electrical DIN rail and has a protection rating of IP20.