Compact Type 1+2 AC Surge Protection for 3P+N Systems
LY1-C40M/4(S) is a compact four-pole pluggable Type 1+2 AC surge protective device designed for three-phase plus neutral distribution systems. Its mini modular construction combines 7kA impulse-current capability with 20kA nominal and 40kA maximum discharge ratings, helping protect multi-phase power circuits while reducing the DIN-rail space required inside distribution panels.
Compact 4P / 3P+N design for three-phase four-wire systems
7kA Iimp, 20kA In, and 40kA Imax surge ratings
75V to 440V AC versions for different low-voltage systems
Pluggable modules with visual status indication and optional remote contact
Suitable Applications
LY1-C40M/4(S) is suitable for three-phase plus neutral AC systems requiring compact Type 1+2 surge protection in distribution boards, machinery panels, automation systems, and other space-limited electrical installations.
Distribution Boards
For compact four-pole surge protection in three-phase plus neutral distribution panels.
Industrial Control Panels
Suitable for machinery controls, automation cabinets, HVAC panels, and industrial power equipment.
Bâtiments commerciaux
Helps protect three-phase building power systems from switching surges and lightning-induced overvoltage.
Solar AC Output Panels
For three-phase solar inverter AC output panels when the voltage version matches the system design.
FAQ
Common questions about LY1-C40M/4(S) compact four-pole pluggable Type 1+2 AC surge protective device selection.
What is LY1-C40M/4(S) used for?
LY1-C40M/4(S) is used for surge protection in compact three-phase plus neutral AC distribution systems, including distribution boards, machinery cabinets, automation systems, HVAC panels, and solar inverter AC output panels.
What does 4P or 3P+N mean?
It means the SPD is designed for three phase conductors plus neutral, allowing coordinated surge protection across all four conductors in a three-phase four-wire system.
What surge ratings does this SPD provide?
The device provides 7kA impulse discharge current Iimp, 20kA nominal discharge current In, and 40kA maximum discharge current Imax.
What voltage options are available?
Maximum continuous operating voltage options include 75V, 150V, 275V, 320V, 385V, and 440V AC. The voltage version must be selected according to the nominal voltage and earthing arrangement of the system.
What is the benefit of the compact pluggable design?
The compact structure reduces DIN-rail space, while the pluggable cartridges allow individual modules to be inspected and replaced without removing the complete wired base.
What should be confirmed before ordering?
Confirm the system voltage, 3P+N circuit arrangement, required surge ratings, 63A maximum backup-fuse coordination, conductor size, available DIN-rail space, and remote-contact requirement.












