BE1-50/51B
3
FUNCTIONAL DESCRIPTION, continued
Table 1 - 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
0.5 to 15.9 Amps
14 Amps
400 Amps
1 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
1 Amp
0.1 to 3.18 Amps
2.8 Amps
80 Amps
0.2 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
Operating power from the power supply is applied to
the microprocessor supervisor circuit. When the input
current falls below an acceptable level, the supervisor
circuit interrupts the microprocessor and halts further
operation.
Figure 1 - Functional Block Diagram
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.