CHAPTER 2: PRODUCT DESCRIPTION SPECIFICATIONS
B90 LOW IMPEDANCE BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL 2-19
2
Triggers: any element pickup, dropout, or operate; contact input change of state; contact output change
of state; FlexLogic equation
Data: AC input channels; element state; contact input state; contact output state
Data storage: in non-volatile memory
EVENT RECORDER
Capacity: 1024 events
Time-tag: to 1 microsecond
Triggers: any element pickup, dropout, or operate; contact input change of state; contact output change
of state; self-test events
Data storage: in non-volatile memory
USER-PROGRAMMABLE FAULT REPORT
Number of elements: 2
Pre-fault trigger: any FlexLogic operand
Fault trigger: any FlexLogic operand
Recorder quantities: 32 (any FlexAnalog
TM
value)
2.5.4 Metering
CURRENT METERING
Accuracy at
0.1 to 2.0 × CT rating: ±0.25% of reading or ±0.1% of rated (whichever is greater)
> 2.0 × CT rating: ±1.0% of reading
VOLTAGE
Accuracy: ±0.5% of reading from 10 to 208 V
FREQUENCY
Accuracy at
V = 0.8 to 1.2 pu: ±0.001 Hz (when voltage signal is used for frequency measurement)
I = 0.1 to 0.25 pu: ±0.005 Hz
I > 0.25 pu: ±0.02 Hz (when current signal is used for frequency measurement)
2.5.5 Inputs
AC CURRENT
CT rated primary: 1 to 50000 A
CT rated secondary: 1 A or 5 A by connection
Relay burden: < 0.2 VA at rated secondary
Conversion range: 0.02 to 46 × CT rating RMS symmetrical
Current withstand: 20 ms at 250 times rated
1 sec at 100 times rated
continuous 4xInom
URs equipped with 24 CT inputs have a maximum operating temperature of 50°C
Short circuit rating: 150000 RMS symmetrical amperes, 250 V maximum (primary current to external CT)
AC VOLTAGE
VT rated secondary: 50.0 to 240.0 V
VT ratio: 1.00 to 24000.00
Relay burden: < 0.25 VA at 120 V
Conversion range: 1 to 275 V
Voltage withstand: continuous at 260 V to neutral
1 min/hr at 420 V to neutral