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Littelfuse.com/Pump-Protection
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Three-Phase Pump Protection
Fully Programmable
777-P2 SERIES
Electronic Overload Relay
Description
The 777-P2 Series is a family of fully programmable electronic
overload relays. They are designed to monitor and protect
any 3-phase 200-480VAC motor drawing 2-800 full load amps
(external CTs are required above 90 amps). They provide
unsurpassed protection from faulty voltage, underload and
overload conditions. The 777-P2 can be used in a variety of
3-phase applications and features an undercurrent trip point
(adjustable on the unit) that is favorable anytime there is a
notable difference between a load and no-load condition. The
overload relay displays voltage and current on the face of the
unit. The LR version is designed for easier installation at a lower
range of 1-9 full load amps. The HVR version is designed with a
high voltage relay for control circuits operating at 480VAC.
The 777-P2 Series units incorporate a 3-digit LED display
that is used for programming, providing real-time operational
information, and displaying diagnostic codes to aid in
troubleshooting a fault condition.
The unit’s many features include enhanced trip classes beyond
the NEMA standard trip classes. The settable trip class range is
2-60, with or without jam protection, and a secondary linear trip
delay can be set with a range of 0-60 seconds. If both trip class
and linear trip delay are set, the 777-P2 will follow the faster trip
time. Another feature is the automatic dry-well recovery timer
that allows the unit to automatically select a restart delay based
on the last cycle’s run time. This allows the 777-P2 to optimize
restart delay times.
Network communications:
compatible with Modbus,
DeviceNet™, Profibus, or Ethernet using optional
communications module.
Specifications
Functional Specifications
Programmable Operating
Points
LV-Low Voltage Threshold
170-524V
HV-High Voltage Threshold
172-528V
VUB-Voltage Unbalance
Threshold
2-25% or 999 (disable)
MULT-# of Conductors or
CT Ratio (xxx:5)
1-10, 100, 150, 200, 300, 400, 500, 600,
700, 800
OC-Overcurrent Threshold
(20-100A) ÷ MULT or 80-140% of CT Primary
UC-Undercurrent Threshold
0, (10-98A) ÷ MULT or 40-140% of CT Primary
CUB-Current Unbalance
Threshold
2-50% or 999 (disable)
TC-Overcurrent Trip Class
2-60, J2-J60, L00-L60, oFF
RD1-Rapid-Cycle Timer
0-999 seconds
RD2-Restart Delay after all
faults except undercurrent
(motor cool down timer)
2-500 minutes
RD3-Restart Delay after
undercurrent (dry-well
recovery timer)
2-500 minutes, A (automatic)
#RU-Number of restarts
after undercurrent
0, 1, 2, 3, 4, A (automatic)
ADDR-RS485 Address
A01-A99
Ordering Information
MODEL
LINE
VOLTAGE
MOTOR FULL
AMP RANGE
DESCRIPTION
777-P2
200-480VAC
(3-phase)
2-800A
(external
CTs required
above 90A)
Provides low and high power
trip*, linear overcurrent trip,
and 480VA @ 240VAC output
SPDT relay contacts
777-LR-P2
200-480VAC
(3-phase)
1-800A
(external
CTs required
above 9A)
Protects low range motors
when wired directly or with
10-800 FLA with use of
external CTs
777-HVR-P2 340-480VAC
(3-phase)
2-800A
(external
CTs required
above 90A)
Provides low and high power
trip*, linear overcurrent
trip, and 470VA @ 600VAC
output SPDT relay contacts.
Required when a control
power transformer (CPT) is
not used with a 480V system
* Network programmable only
