Basler Electric BE1-79M - Manual (Page 32)

3-8 BE1-79M Functional Description 9170100990 Rev N
The lockout output contacts close and the LOCKOUT LED lights to indicate lockout. LOCKOUT is termi-
nated when the controlled breaker is closed (manually or by other means) and remains closed for the
duration of the reset time delay setting.
Reclosing Sequences
The BE1-79M Multiple Shot Reclosing Relay can generate three types of reclosing sequences. Each type
is described in the following paragraphs and illustrated in Figure 3-5 and Figure 3-6.
• Reclose Initiated Sequence
•
- Initiated by the 52b and RI signals, this sequence produces one in-
stantaneous reclosing attempt followed by up to three time-delayed reclosing attempts. All
reclose command outputs occur through the reclose output contacts in this sequence.
Reclose Initiated Sequence with Instantaneous Reclose Bypass
•
- Initiated by the 52b, RI, and
IRB signals, this sequence produces up to three time-delayed reclosing attempts. All reclose
command outputs occur through the reclose output contacts in this sequence.
Pilot Initiated Sequence
Each reclose attempt requires the presence of either the RI or PI contact input before the respective
reclose sequence can be performed. The RI input must also be present prior to each individual time
delay.
- Initiated by the 52b and PI signals, this sequence produces one instan-
taneous reclosing attempt through the pilot output contacts, and up to two time-delayed reclosing
attempts through the reclose output contacts. The time-delayed reclosing attempts are controlled
by RECLOSE TIME delay settings 2 and 3. RECLOSE TIME delay setting 1 is bypassed in this
sequence (unless set to 000, in which case the relay drives to LOCKOUT). The IRB signal has no
influence on this sequence.
When a Pilot Initiated reclose sequence has been started by the presence of the PI input, the associated
closure of the reclose output relay also requires the presence of the PI input. If the breaker re-opens after
the instantaneous closure of the reclose output relay, then the RI or PI input must be present in order for
the second reclose time delay to occur. The RI or PI input must also be present for the third time delay.
The flow chart of Figure 3-6 is a simplified representation of reclosing sequence initiation and progres-
sion. In actual operation all reclosing attempts are continuous (as indicated by the dashed lines) unless
limited by the reclose fail or maximum cycle options. The number of reclosing attempts may be limited by
adjusting any one of the reclose time delay settings to 000. This produces LOCKOUT when a breaker trip
occurs at this point in a reclosing sequence.
Reclose Fail
The reclose fail option allows the user to limit the duration of reclose command outputs. If the breaker fails
to respond to the reclose command in the allotted time, the reclose fail and lockout contacts close and
their associated LEDs light. The first reclosure attempt in a pilot initiated reclosing sequence is continuous
regardless of the reclose fail setting. All reclose command outputs are continuous if the reclose fail option
is not present or if the RECLOSE FAIL setting is 00.
Maximum Cycle
The maximum cycle option limits the duration of a reclosing sequence as determined from sequence
initiation (presence of 52b and RI or PI) to automatic relay RESET or LOCKOUT. If RESET or LOCKOUT
is not reached in the allotted time, the MAX. CYCLE LED lights and the relay drives to LOCKOUT.
Block Load Tap Changer
The optional block load tap changer output contacts are opened to disable automatic transformer load tap
changer operations while a reclosing sequence is in progress.