Additional Functional Testing; Overload Curve Test - GE 469 Instruction Manual

7 TESTING

7.3ADDITIONAL FUNCTIONAL TESTING

The 469 specification for overload curve timing accuracy is ±100 ms or ±2% of time to trip. Pickup accuracy is as per the
current inputs (±0.5% of 2 × CT when the injected current is less than 2 × CT and ±1% of 20 × CT when the injected current
is ≥ 2 × CT). Perform the steps below to verify accuracy.
1. Alter the following setpoints:
Õ
S2 SYSTEM SETUP
Õ
S2 SYSTEM SETUP
S5 THERMAL MODEL
S5 THERMAL MODEL
S5 THERMAL MODEL
S5 THERMAL MODEL
S5 THERMAL MODEL
S5 THERMAL MODEL
2. Any trip must be reset prior to each test. Short the emergency restart terminals momentarily immediately prior to each
overload curve test to ensure that the thermal capacity used is zero. Failure to do so will result in shorter trip times.
Inject the current of the proper amplitude to obtain the values as shown and verify the trip times. Motor load may be
viewed in:
A2 METERING DATA
3. Thermal capacity used and estimated time to trip may be viewed in:
Õ
A1 STATUS MOTOR STATUS
AVERAGE PHASE
CURRENT
DISPLAYED
1050 A
1200 A
1750 A
3000 A
6000 A
10000 A
GE Multilin
Courtesy of NationalSwitchgear.com
Õ
CURRENT SENSING PHASE CT PRIMARY:
Õ×
CURRENT SENSING MOTOR FULL LOAD AMPS FLA:
Õ Õ
THERMAL MODEL SELECT CURVE STYLE:
Õ Õ×
THERMAL MODEL OVERLOAD PICKUP LEVEL:
Õ Õ×
THERMAL MODEL UNBALANCE BIAS K FACTOR:
Õ Õ×
THERMAL MODEL HOT/COLD SAFE STALL RATIO:
Õ Õ×
THERMAL MODEL ENABLE RTD BIASING:
Õ× Õ
O/L CURVE SETUP STANDARD OVERLOAD CURVE NUMBER:
Õ
CURRENT METERING
PICKUP LEVEL EXPECTED
TIME TO TRIP
1.05 never
1.20 795.44 sec.
1.75 169.66 sec.
3.00 43.73 sec.
6.00 9.99 sec.
10.00 5.55 sec.
469 Motor Management Relay
7.3 ADDITIONAL FUNCTIONAL TESTING

7.3.1 OVERLOAD CURVE TEST

"1000"
"1000"
"Standard"
"1.10"
"0"
"1.00"
"No"
"4"
TOLERANCE RANGE MEASURED
TIME TO TRIP
n/a
779.53 to 811.35 sec.
166.27 to 173.05 sec.
42.86 to 44.60 sec.
9.79 to 10.19 sec.
5.44 to 5.66 sec.
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