Basler BE1-51B Manual - Functional Description
BE1-50/51B Retrofit Kits
3
FUNCTIONAL DESCRIPTION
Table 2. Current Sensing Capabilities
Time Element
Time Element
50/60 Hz System
Time Element Max. Continuous Max. Current
Instantaneous
Time Element
Instantaneous
CT Secondary
Pickup Range
Current
For 1 Second
Pickup Range
Pickup Accuracy
Pickup Accuracy
5 Amp models 0.5 to 15.9 Amps
14 Amps
400 Amps
A: 2 to 99 Amps
2% from 0.5 to
2% from 1 to 99 Amps
in 0.1 Amp steps
in 1 Amp Steps
15.9 Amps
B: 1 to 15.9 Amps
in 0.1 Amp Steps
1 Amp models 0.1 to 3.18 Amps
2.8 Amps
80 Amps
A: 0.4 to 19.8 Amps
2% from 0.1 to 2% from 0.2 to 19.8 Amps
in .02 Amp steps
in 0.2 Amp Steps
3.18 Amps
B: 0.2 to 3.18 Amps
in 0.02 Amp Steps
CURRENT INPUT
A single phase of ac current from a 5 Amp, or 1 Amp,
50/60 Hz, system current transformer (CT) is applied to
the BE1-50/51B. This input current provides both the
power and sensing quantity for the relay.
The current applied to the relay provides the energy for
the internal power supply. When sufficient current is
available, the Active/Pickup LED will turn green. In appli-
cations where circuit loading conditions are less than
that required to illuminate the LED, the relay remains
operable and will provide overcurrent protection.
MICROPROCESSOR
The setting of the TIME DIAL, TIME CURVE selector switch,
and circuit board jumpers provide the micro-processor
with ten operating parameters for the desired response by
the relay. The microprocessor performs the program
operations based on the input current level and internal
software program. When the Active/Pickup LED is green,
the microprocessor is active and executing code.
The watchdog timer monitors the microprocessor for
specific pulses indicating proper program operation. If
something occurs to disrupt the microprocessor, these
pulses stop, the watchdog timer times out and sends a
reset pulse to the microprocessor. The microprocessor
resets and resumes normal operation.
TIME ELEMENT CHARACTERISTIC SHAPES
FOR CO and BS142 CURVES
All time characteristic curves follow the relation:
T
T
= AD + BD + K = Time to trip
M
N
-C
T
R
= RD = Time for decaying reset
M
2
-1
Actual curve constants are available in the Instruction
Manual. See page 1 of this bulletin for applicable publica-
tion number.
The Active/Pickup LED on the front panel will turn red when
the applied current just exceeds the PICKUP setting.
Table 1.
Curve Type
Basler
Type
Similar To
S1
Short Inverse
ABB CO-2
S2
Short Inverse
GE-IAC-55
L1
Long Inverse
ABB CO-5
L2
Long Inverse
GE IAC-66
D1, D2
Definite Inverse
ABB CO-6
M1, M2
Definite Inverse
ABB CO-7
I1
Inverse
ABB CO-8
I2
Inverse
GE IAC-51
V1
Very Inverse
ABB CO-9
V2
Very Inverse
GE IAC53
E1
Extremely Inverse
ABB CO-11
E2
Extremely Inverse
GE IAC 77
B
British Standard
BS 142-B
Very Inverse
C
British Standard
BS 142-C
Extremely Inverse
F
Fixed Time
none
RESET
Reset occurs when the current level is less than pickup.
Internal switch provides selection of either an Instanta-
neous or a decaying reset characteristic.
The instantaneous reset characteristic forces the timer to
zero when the input current falls below 95% of setting. This
fast reset characteristic prevents the ratcheting effect on
electromechanical relay disks that occurs for repeated
faults.
The decaying reset characteristic replicates the decaying
reset of electromechanical relay disks. When enabled, the
relay will continue the decaying process even when the
input current goes to zero.
INSTANTANEOUS ELEMENT CHARACTERISTICS
The characteristic for phase faults is faster because the
relay will be powered-up. However, the tripping character-
istic for ground applications is slightly longer to allow time
to power-up the relay. This longer trip time for ground
applications is beneficial because it helps avoid nuisance
trips. These timing characteristics are shown in Figure 2.