Protection Relays
Voltage Monitoring Relays
455 SERIES
3-Phase Voltage/Phase Monitor
Description
The 455 Series are 3-phase voltage monitors that combine load
and line side monitoring to offer complete protection. Monitoring
the load side will alert the user of contactor failure or impending
contactor failure. Line side monitoring will also protect the
motor from damaging fault conditions that may be present prior
to the motor starting. With other line/load side monitors, the
motor must be started before a voltage fault is detected. With
the 455, your motor is fully protected at all times.
The 455 Series are 3-phase, dual range voltage monitors that
protect 190-480VAC, 50*/60Hz motors, regardless of their size.
It automatically selects between the 200V and 400V range
when the user selects the nominal voltage setpoint. Other
adjustments include a 2-30 second trip delay, a 2-300 second
restart delay (and manual restart) and a voltage unbalance
trip point of 2-8%. The voltage monitor’s circuitry is powered
through the line side connections, so there is no need for
separate control power, making it easy to install.
Equipped with an infrared LED, the 455 Sereies can
communicate to the optional hand-held diagnostic tool,
Informer-MS to obtain valuable information such as real-time
voltage, voltage unbalance on both line and load sides, motor
run hours, last 20 faults, last 32 motor starts, high and low
voltage trip points, voltage unbalance trip point, restart and trip
delay settings, LED status and more.
Wiring Diagram
MODEL 455 WITH MOTOR CONTROL USING A 3-POLE CONTACTOR
Features & Benefits
FEATURES
Load side monitoring
of contactor
Monitors contactor
or starter
Infrared LED Capable
BENEFITS
Protects motor from contactor failure or worn
contacts.
Prevents rapid cycling
Increases personnel safety line of sight monitoring
using optional Informer-MS
MODEL 455 WITH MOTOR CONTROL USING A 2-POLE CONTACTOR
Accessories
Informer-MS
A hand-held diagnostic tool designed for use
with Littelfuse
®
455 equipped with an infrared
LED transmitter
Informer IR Kit-36
36” infrared adapter cable attaches to the face
of the unit to provide remote diagnostics without
opening the panel.
Ordering Information
MODEL
LINE VOLTAGE DESCRIPTION
455
455480R
455575
© 2016 Littelfuse Protection Relays & Controls
www.littelfuse.com/455
www.littelfuse.com/
190-480VAC
380-480VAC
475-600VAC
Universal line and load side monitor
Used in high voltage applications with pilot
duty 470VA @ 600VAC
For use in Canada or NE USA where 575V
utility power services are common.
Rev: 1-A-062116
Protection Relays
Voltage Monitoring Relays
455 SERIES
Specifications
Specifications
Frequency
Low Voltage (% of setpoint)
Trip
Reset
High Voltage (% of setpoint)
Trip
Reset
Voltage Unbalance (NEMA)
Trip
Reset
Trip Delay Time
Low & High Voltage
and Unbalance
Single-phasing Faults
(>25% UB)
Restart Delay Time
After a Fault
After a Complete Power Loss
After a Motor Shut-down
Output Characteristics
Output Contact Rating (SPDT)
Pilot Duty
General Purpose
High Voltage Relay (-480R)
Pilot Duty
50*/60Hz
90% ±1%
93% ±1%
110% ±1%
107% ±1%
2-8% adjustable
Trip setting minus 1%
2-30 seconds adjustable
2 seconds fixed
Manual, 2-300 seconds adj.
Manual, 2-300 seconds adj.
Manual, 2-300 seconds adj.
General Characteristics
Ambient Temperature Range
Operating
Storage
Repeat Accuracy
Fixed Conditions
Maximum Input Power
Terminal
Torque
Wire Size
Transient Protection
(Internal)
Safety Marks
UL
CSA
CE
Dimensions
Weight
Mounting Method
-40° to 70°C (-40° to 158°F)
-40° to 80°C (-40° to 176°F)
±0.1%
6W
7 in.-lbs.
12-18AWG
IEC 61000-4-5;1995 ±6kV
UL508 (File #E68520)
C22.2 No. 14 (File #46510)
IEC 60947-6-2
H
74.4 mm (2.93”);
W
133.9 mm (5.27”);
D
74.9 mm (2.95”)
1.1 lbs. (17.6 oz., 498.95 g)
#8 screws
*Note: 50Hz will increase all delay times by 20%.
480VA @ 240VAC
10A
470VA @ 600VAC
© 2016 Littelfuse Protection Relays & Controls
www.littelfuse.com/455
www.littelfuse.com/
Rev: 1-A-062116