Basler BE1-50BF, Инструкция по эксплуатации

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9190600990 Rev F BE1-50BF Functional Description 3-1
SECTION 3
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FUNCTIONAL DESCRIPTION
GENERAL
BE1-50BF Breaker Failure Relays are static devices designed to detect circuit breaker failure, and to trip
backup circuit breakers when such failures are detected.
FUNCTIONAL DESCRIPTION
Relay circuit functions illustrated in Figure 3-1 are described in the following paragraphs.
Figure 3-1. Functional Block Diagram
Contact Sensing
Before any relay output can occur, there must first be an initiating signal from external contacts. Two
possible initiating signals are either the breaker failure initiate (BFI) signal or the optional supervisory
signal. Contact sensing circuitry allows the relay to monitor external contacts for the presence of these
signals.
Contact sensing inputs must use either isolated sensing or non-isolated sensing. Isolated sensing (option
1-5) uses current supplied by the relay to monitor external contacts. Non-isolated sensing uses an
external dc source to monitor the contacts. Nominal voltages of the external dc source must match the dc
input voltages of the relay power supply. If the power supply of the relay has an ac source, a separate dc
source must be utilized for the contact sensing input.
Instantaneous Output - Optional
Instantaneous output relays are enabled whenever a BFI contact closure and enabling switch S1-1 is
closed. They are also enabled whenever a supervisory contact closure is detected and enabling switch
S1-2 is closed. S1-3, when closed, seals the instantaneous relays through the BFI input. Instantaneous