ELECTRICAL ENVIRONMENT REQUIRED FOR THE PROTECTIVE RELAYS

 THE FOLLOWING INFORMATIONS APPLY TO RELAYS

INPUT ENERGISING QUANTITIES

AC Voltages (rms)   115V

AC Current (rms)     1Amp or 5 Amps

AUXILIARY ENERGISING QUANTITIES

Fixed Inputs	Level sensitive inputs	Jumper selectable inputs
30Vdc	18Vdc	30Vdc
48Vdc	28.8Vdc	48Vdc
110Vdc	66Vdc	110Vdc
220Vdc	132Vdc	220Vdc

 

FREQUENCY 

Specified as 50Hz with a range of operation from 47.5Hz to 52.5Hz

REFERENCE CONDITIONS OF INFLUENCING QUANTITIES 

Ambient temperature = 355°C

Position  =  Horizontal

NOMINAL RANGE OF INFLUENCING QUANTITIES

Unless otherwise specified, the following values represent the reference condition Ambient temperature -40°C to 85°C

Position 0° to 180°in any direction from the reference position

LIMITING SHORT TIME THERMAL WITH STAND

Current Inputs                       Voltage Inputs 500amps (ac) for 1see                                                  365v (ac) for 10 sec

 

The above conditions are to be verified for the acceptance of relays for the pre-commissioning test on protective relays.

Protective relays have been called sentinels and electric brains.

From the economic point of view, relays are akin to insurance; they protect the power utility from financial loss due to damage to equipment.

From the under writers point of view, they prevent accidents to personnel and minimise damage to equipments.

From the consumer’s point of view, good service depends more upon adequate relaying than upon any other equipment.