AUMSHIVAY ENGINEERING PRIVATE LIMITED
B-21, Bhan Nagar, Queens Road, Jaipur-302021
Website: www.aumshivay.com, www.omengineering.in
E-mail:admin@aumshivay.com
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REG. OFFICE:VILLA NO. 60,LATA NAGAR, KALWAR ROAD, JHOTWARA, JAIPUR - 302012
Motor Protection Relay (MPR300); These are Microprocessor based Motor protection relay. The relay has got
inbuilt CTs for motor sizes up to 50KW (i.e 88 A current). They provide the protection from Thermal Overload, Earth Fault,
Single Phasing, Locked Rotor, Under Current. Relay MPR300 is a three-phase motor protection relay for motor sizes up to 50KW
(max. 88 A current). It is a low cost solution, offering five major protections for motors widely used in fans, pumps, crushers,
mills, compressors, belt conveyors, centrifuges, mixers, ventilators, escalators, motorized valves etc. Major advantage is that it
provides E/F co-ordination in contactor-started motors, thus offering greater security, operator safety and economy. The relay is
micro controller based, highly user friendly and compact with inbuilt CTs. The relay can also be used for protection of larger
motors by using external CTs. medium voltage and high voltage sub-stations.
MPR300 has very few controls / settings on the front panel. There are two
potentiometers –one for setting the motor rated current and the other for setting
the E/F pick up level. A DIP switch is provided for selection of thermal overload trip
class and enable / disable of Locked rotor protection and under current protection.
Other settings are prefixed in the relay (some of them related to the trip class
selected). Six LEDs are provided –five to indicate the faults and one to indicate
power on condition. There are two push buttons- one to reset the LEDs on clearance
of fault and the other to test the relay. The test PB operation runs a small software
routine, which performers check on all software & hardware blocks internal to relay.
MOTOR PROTECTION RELAY (MPR300)
MPR300 Mini Motor Protection Relay
All data pertaining to pick up level and applicable time
delays are indicated on a label on right hand side of the
unit. The wiring diagram label is provided on the left
hand side of the unit.
*Motor Full load current Im
*E/F pick up level Io
*Trip time characteristic (Class 10A, 10, 20, 30)
*Enable / Disable Locked Rotor
The pick up levels and time delays for negative sequence,
locked rotor and under current protections are preset in
the relay.
*R-Y-B phase wires pass through relay.
*Trip contacts to be wired to starter.
MPR 300 offers you greater security, operator safety
through proper co-ordination in case of earth fault on
motor feeder.
MPR300 is used for protection of motors widely used in
fans, pumps, crushers, mills, compressors, belt conveyors,
centrifuges, mixers, ventilators, escalators, motorized
valves etc.
