Protection of induction motors against single phasing or reverse phasing or unbalance
supply is one of the major problems in electrical systems. For safe running of 3-phase
motors, special protections that keep a continuous watch on supply conditions are very
essentials. The major cause of maxium motors burn-out is overloading which occurs
due to unbalance supply or single phasing. Phase failure occurs in case of fuse
blown-off, loose connections or loss of phase from supply itself.
'PROTONs MULTIFUNCTION RELAY - SPP 2' offer these protections along with
LOW/HIGH voltage tripping to ensure the trouble free running of 3-phase motors.
SALIENT FEATURES :
•
Operates on the principle of sensing negative sequence components of the system.
•
Suitable for the protections of motors of any H.P.
•
Protection against single phasing, reverse phasing, unbalance supply, under/over voltage.
•
Variable trip voltage setting for under/over voltage protection. Fixed unbalance trip setting
at 40 volts.
•
No separate auxiliary supply required.
•
Individual trip indication for under voltage, over voltage, single phasing, reverse phasing
and indication for output relay ON.
•
Auto reset type voltage hysterisisgap for tripping on under/over voltage.
TECHNICAL SPECIFICATION :
System Supply
: 415 VAC, Three phase +/- 10%
Output Contacts
: One changeover ( C-NO-NC)
Output contact rating
: 5 Amps at 230 V AC.
Trip Time delay
: 2-3 seconds.
Variable Voltage Setting
: For Under voltage,
330 TO 370 VAC.
: For Over voltage,
430 TO 470 VAC.
Reset Mode
: Auto reset.
Trip Indications
For over voltage, under voltage, single phasing
and reverse phasing and relay ON indication.
Unbalance trip setting
: Fixed at 40 Volts between any two phases.
Temperature range
: -5 0C to 60 0C.
Relative humidity
: 95% R.H.
Mounting
: Din rail.
: Base mounting dimensions
55 (W) x 65 (L) x 125 (D) mm.
Auxiliary Supply
: 24 V DC, +/- 10% (optional feature)
* Due to continuous change, specifications are subject to change
without notice.
