Eaton Logo

What are the differences for UL 1449 3rd edition for surge protection

UL 1449 3rd Edition gives four
designations to surge protective
devices depending on where in
the electrical system the device is
connected.
• Type 1 — Permanently connected
device installed before
or after the service disconnect
overcurrent device and
intended to be installed with no
external overcurrent protective
device. This type of SPD most
closely relates to
devices that were called secondary
surge
arrestors prior to 3rd Edition.
• Type 2 — Permanently connected
device installed after the
service disconnect overcurrent
device. This type of SPD most
closely relates to devices that
were called transient voltage
surge suppressors prior to 3rd
Edition.
• Type 3 — Point of use SPDs
that are installed with a minimum
of 30 feet of conductor
length from the service panel.
These 30 feet of conductor
length does not include conductors
used to attach the
SPD. Some examples of Type
3 SPDs are cord connected,
direct plug-in and receptacle
type SPDs.
• Type 4 — Component SPDs
and component assemblies.