Control; Associated Breaker Command; Operation Failure Detection - GE SMOR-B GEK 105593C Instructions Manual

2.4. CONTROL

Using a local interface (MMI) or using a personal computer connected to the serial port with the GE-LOCAL
communications software, it is possible to open or close the line breaker using the tripping or closing
contacts of the SMOR unit.
The SMOR unit detects breaker failure-to-open and also failure-to-close conditions.
When a closing command is issued, a timer starts. This timer can be set to a value for "MAXIMUM
CLOSURE TIME", programming it for the maximum time expected for the closing of the breaker. If this timer
produces an output (when time exceeds the setting) it issues an alarm which indicates that the breaker has
not closed in the expected time. If the breaker closes before this time, the timer is stopped by the opening of
a contact 52/b which is wired to the digital input associated with this function, and the alarm is not turned on.
If the contact 52/b is not wired to the SMOR system, no voltage is applied when the breaker is open (contact
52/b closed). In this case the timer does not start when the breaker closing signal is issued, and therefore the
failure-to-close detection function cannot operate.
As far as the failure-to-open detection is concerned, the SMOR unit is provided with a logic activated by the
OR of the trip of any of the internal protection units in which a trip is permitted and by the activation of a
failure-to-open input. Once the OR-A gate has been activated, the failure-to-open unit will act if the breaker
remains closed at the end of the time period set for "MAXIMUM OPENING TIME", or if any of the overcurrent
units of the SMOR are still picked up (outputs OR-B and OR-C). This arrangement corresponds to the
following logical diagram:
Trip
OR A
Failure to
open
O/C Pickup
52 Closed
OR B
Breaker Failure-to-open function logic
GEK-105593C

2.4.1. ASSOCIATED BREAKER COMMAND

2.4.2. OPERATION FAILURE DETECTION

T
0.05-1
OR C
17
AND A
Breaker
failure to open