Mersen Surge Protector Type 1+2 SPD 3 Pole 480 Volt 20KA TNC Remote Indication
Mersen STPT12-12K320V-3PM Type 1+2 pluggable surge protection device with 12.5 kA lightning impulse current, 320 V maximum continuous operating voltage, 277/480 V AC nominal voltage, 3 pole 3+0 TNC configuration, remote indication and DIN rail mounting.
This product has been discontinuedA direct replacement is available below.
Why Choose the Mersen 83120133 Surge Protection Device?
The Mersen 83120133 STPT12-12K320V-3PM is a high-performance Type 1+2 Surge Protection Device (SPD) designed to protect low voltage electrical installations against transient overvoltages caused by lightning activity and switching events. As part of the Mersen Surge-Trap® Pluggable STPT12 Series, it provides dependable first-stage surge protection for industrial, commercial and infrastructure power distribution systems.
This pluggable SPD combines Class I and Class II surge protection in a compact DIN rail mounted format. Its replaceable cartridge design, visual status indication and integrated remote signalling contact make it suitable for applications where quick maintenance, monitoring and long-term system reliability are important.
With a 12.5 kA lightning impulse current rating, 277/480 V nominal operating voltage and 320 V maximum continuous operating voltage, the Mersen 83120133 is ideal for protecting three-phase TNC distribution systems, switchboards, control panels and sensitive electrical equipment from damaging voltage surges.
Key Advantages
Combined Type 1+2 surge protection for low voltage installations.
12.5 kA lightning impulse current (Iimp) for robust surge handling.
320 V maximum continuous operating voltage for 277/480 V systems.
Integrated remote indication for external SPD status monitoring.
Pluggable cartridge design supports quick replacement and maintenance.
Compact 3-pole, 3-module DIN rail format.
Key Features
Mersen Surge-Trap® Pluggable STPT12 Series.
Type 1+2 / Class I+II surge protection device.
12.5 kA Iimp (10/350 μs).
50 kA maximum discharge current (Imax 8/20 μs).
20 kA nominal discharge current (In 8/20 μs).
277/480 V nominal operating voltage.
320 V maximum continuous operating voltage.
3-pole configuration for 3+0 TNC systems.
Remote signalling contact for status monitoring.
DIN rail mounted IP20 construction.
Reliable Protection Against Electrical Surges
Surge protection devices help protect electrical systems by safely limiting transient overvoltages before they reach connected equipment. This reduces the risk of damage to switchgear, control systems, drives, PLCs, instrumentation, power supplies and other sensitive electrical components.
The Mersen STPT12 range is designed for use as the first level of protection in main distribution boards and incoming supply panels. Its Type 1+2 classification makes it suitable for installations exposed to atmospheric surges and applications requiring coordinated protection against lightning currents and voltage spikes.
Typical Applications
Main low voltage distribution boards.
Incoming power supply panels.
Three-phase TNC electrical systems.
Industrial automation and control panels.
Commercial building electrical installations.
Switchboards, panel building and infrastructure systems.
Technical Specifications
Voltage
480 V
Phase
Three Phase
Manufacturer
Mersen
Series
Surge-Trap® Pluggable STPT12
Model
STPT12-12K320V-3PM
SKU
83120133
Product type
Type 1+2 Surge Protection Device
IEC classification
Class I+II
Lightning impulse current (Iimp)
12.5 kA (10/350 μs)
Maximum discharge current (Imax)
50 kA (8/20 μs)
Nominal discharge current (In)
20 kA (8/20 μs)
Nominal operating voltage (Un)
277/480 V AC
Maximum continuous operating voltage (Uc)
320 V
System configuration
3+0 TNC
Network type
3 phase
Number of poles
3
Number of modules
3
Mounting type
35 mm DIN rail
Protection rating
IP20
Remote indication
Yes
Format
Pluggable
EAN / UPC code
8435297851493
HS Code
85363090
Country of Manufacture
Spain
Frequently Asked Questions
What is the Mersen 83120133 used for?
It is used to protect low voltage electrical installations against transient overvoltages caused by lightning activity and switching events.
What type of surge protection does this device provide?
The Mersen 83120133 provides combined Type 1+2 / Class I+II surge protection.
Does this SPD include remote indication?
Yes. The device includes remote indication, allowing the surge protection status to be monitored externally.
What is the maximum continuous operating voltage?
The device has a 320 V maximum continuous operating voltage, making it suitable for 277/480 V AC systems.
Where is this surge protection device typically installed?
It is typically installed on a DIN rail inside main distribution boards, incoming panels or electrical switchboards.
Trusted for Critical Power Protection
Mersen Surge-Trap® surge protection devices are trusted by electrical engineers, panel builders and industrial facilities worldwide for dependable protection of power distribution systems and sensitive connected equipment.
Voltage
480 V
Phase
Three Phase
Manufacturer
Mersen
Series
Surge-Trap® Pluggable STPT12
Model
STPT12-12K320V-3PM
SKU
83120133
Product type
Type 1+2 Surge Protection Device
IEC classification
Class I+II
Lightning impulse current (Iimp)
12.5 kA (10/350 μs)
Maximum discharge current (Imax)
50 kA (8/20 μs)
Nominal discharge current (In)
20 kA (8/20 μs)
Nominal operating voltage (Un)
277/480 V AC
Maximum continuous operating voltage (Uc)
320 V
System configuration
3+0 TNC
Network type
3 phase
Number of poles
3
Number of modules
3
Mounting type
35 mm DIN rail
Protection rating
IP20
Remote indication
Yes
Format
Pluggable
EAN / UPC code
8435297851493
HS Code
85363090
Country of Manufacture
Spain
No documents available for this product.
Delivery
We offer fast UK delivery on all stocked items. Orders placed before 3pm Monday to Friday are eligible for next-day delivery.
Standard delivery: 2–3 working days
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Customers supported
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2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...