Eaton Cutler Hammer OEM Contact Kit 6-26-2 3 Pole
The MP-3000 Motor Protection Relay has been designed for maximum
motor utilization and protection. It is desirable to run the motor as
close as possible to its design limits, while protecting it against exces
sive heating and damaging overload conditions. The MP-3000 has
ield-proven protection algorithms developed from basic motor design
principles and operating parameters.
The MP-3000 protects against rotor and stator overheating, short
circuits or insulation faults, excessive starting duty, and abnormal
operating conditions.
2.1.1 Intel-I-Trip (adaptive I2t Motor Overload Protection)
Motor operation is typically limited by the rotor thermal capabilities, but
the measuring quantities are stator currents. This requires accurate
measurements and good motor thermal models to provide maximum
utilization and reliable protection.
The MP-3000 uses the field-proven Intel-I-Trip overload measure
ment and motor thermal protection model that uses the manufacturer’s
nameplate data to develop an overload protection curve specifically for
the motor being protected. When RTDs are used, the Intel-I-Trip over
load protection curve becomes adaptive. The overload trip times will
change based on the modeling impact of the motor’s internal tempera
ture data. It also trips directly for high stator temperature.
The relay samples the current waveforms 36 times per cycle provid
ing accurate measurements of the positive and negative sequence
currents, as well as harmonic components that add to rotor and stator
heating. The negative sequence component of current causes far
greater heating effect on the rotor and has a greater impact on the
thermal model in the relay, as compared to the balanced or positive
sequence component.
2.1.2 Instantaneous Overcurrent Protection
The MP-3000 has an instantaneous phase overcurrent function to trip
the motor for fault currents, sometimes saving the fuses for medium
current faults. This function can be disabled and has an adjustable
start time delay on starting to avoid nuisance tripping on inrush.
2.1.3 Phase Current Unbalance Protection
Motor supply circuits are often fed through fuses and may be ener
gized with one fuse blown, causing single phasing of the motor. The
MP-3000 measures the current unbalance and can be used to alarm
or trip the motor before heating and a thermal-model trip. Pickup, start
and run timers, and separate alarm settings are provided.
2.1.4 Ground fault Protection
A separate monitoring circuit is used to measure ground current. A
zero sequence ground CT is recommended for more sensitive protec
tion against winding insulation failure to ground. The relay ground CT
input can be connected residually from the three phase CTs, but with
much inferior protection sensitivity. The ground fault protection has
adjustable pickup and time delay set points, or it can be disabled.
3 MP-3000 Motor Protection Relay accessories.
Catalog Number Description Style Number
URTD Module Universal RTD Module 2D78559G01
IQDCPS IQ DC dc to ac power supply converter, 100 – 150 Vdc 2D78542G01
MPFO-1 1 Meter precut optical fiber link for URTD with connectors 66D2037G01
MPFO-5 5 Meter precut optical fiber link for URTD with connectors 66D2037G02
MPFO-10 10 Meter precut optical fiber link for URTD with connectors 66D2037G03
MPFO-25 25 Meter precut optical fiber link for URTD with connectors 66D2037G04
MPFO-50 50 Meter precut optical fiber link for URTD with connectors 66D2037G07
MPFO-75 75 Meter precut optical fiber link for URTD with connectors 66D2037G10
MPFO-76 76 Meter precut optical fiber link for URTD with connectors 66D2037G11
MPFO-100 100 Meter precut optical fiber link for URTD with connectors 66D2037G13
MPFO-120 120 Meter precut optical fiber link for URTD with connectors 66D2037G14
MP3BRACKET PONI Mounting Bracket 66D2053G01
MPML Relay mounting plate adapter with 1/2” Stud – fits GE Multilin® 269 cutout 66D2044G01
MPML-L Relay mounting plate adapter with 1” Stud – fits GE Multilin® 269 cutout 66D2044G02
EPONI Ethernet communications module 66D2028G01
EPONIF Ethernet optical fiber communications module 66D2028G02
IPONI INCOM communications module 8793C36G03
DPONI Data communications module 6D2132G01
RS-485 PONI Modbus RTU communications module 66D2042G01
MD3000 Motor/Generator Differential Relay Fixed Case 66D2126G01
MD3001 Motor/Generator Differential Relay Drawout Case 66D2127G01