Compact 3-Pole Surge Protection for AC Distribution Systems
LY1-D20/3(S) is a pluggable three-pole Type 2 AC surge protective
device designed to limit transient overvoltages in low-voltage
distribution systems. It is suitable for sub-distribution boards,
industrial control cabinets, machinery panels, and commercial
electrical installations requiring compact multi-pole protection.
Type 2 protection for low-voltage AC distribution systems
10kA nominal and 20kA maximum discharge current per pole
Pluggable cartridge design simplifies inspection and replacement
Visual status indication with optional remote signalling on the S version
Suitable Applications
LY1-D20/3(S) is suitable for low-voltage AC systems where compact
three-pole Type 2 surge protection is required at downstream
distribution and equipment protection points.
Sub-Distribution Boards
For downstream AC distribution boards in residential, commercial,
and industrial electrical systems.
Industrial Control Cabinets
Helps protect PLCs, relays, power supplies, and other sensitive
control components from transient overvoltages.
Machinery Panels
Suitable for surge protection in production machinery,
automation equipment, and electrical control panels.
OEM Electrical Panels
Compact DIN-rail surge protection for OEM switchboards,
customized enclosures, and power distribution assemblies.
FAQ
Common questions about LY1-D20/3(S) three-pole Type 2 AC surge
protective device selection, installation, and maintenance.
What type of surge protective device is LY1-D20/3(S)?
LY1-D20/3(S) is a three-pole Type 2 / Class II surge protective
device designed for low-voltage AC distribution systems. It
limits transient overvoltages caused by induced lightning
surges and electrical switching operations.
What surge ratings does this AC SPD provide?
The nominal discharge current In is 10kA and the maximum
discharge current Imax is 20kA, both measured with an
8/20μs current waveform.
Which Uc voltage versions are available?
Available maximum continuous operating voltage Uc versions
include 75V, 150V, 275V, 320V, 385V, and 440V AC. The correct
version must be selected according to the system voltage and
earthing arrangement.
What is the benefit of the pluggable design?
The pluggable cartridge design allows a protection module to
be inspected or replaced without removing the complete DIN-rail
base, helping reduce rewiring work and maintenance time.
Does LY1-D20/3(S) support remote signalling?
Yes. The LY1-D20/3S version can include an optional remote
signalling contact for connection to an alarm, control panel,
or monitoring system.
Where is LY1-D20/3(S) normally installed?
It is commonly installed in sub-distribution boards, industrial
control cabinets, machinery panels, commercial electrical
systems, and customized OEM distribution equipment.
What should be confirmed before ordering?
Please confirm the nominal AC voltage, required Uc rating,
earthing arrangement, pole configuration, backup fuse,
conductor size, installation space, and remote signalling
requirement before ordering.
