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10 - MAJOR SYSTEM COMPONENTS AND OPERATION DATA
10.8.7 -
State diagram
The logic of the relay is illustrated per below state diagram during normal operation:
A1/A2
(supply)
INF
(feedback circuit)
SP-F
(HPS sensor)
SP-FA
(HPS sensor)
Safety related
outputs
Typical
situations:
Power-up
Auto-check of contactor
feedback circuit and
HPS sensors inputs
Normal operation
incl. standby
Both HPS
sensor trip
Only one HPS
sensor trips
Power-up
Auto-check of contactor
feedback circuit and
HPS sensors inputs
Auto-check of contactor
feedback circuit prevents
from restart due to
malfunction of contactor
Restart allowed after
auto-check of contactor
feedback circuit and
HPS sensors inputs
Restart not allowed due
to discordance of HPS
sensor inputs
Normal operating conditions
One or bothes
HPS sensor trips but
contactor feedback circuit
stays open (contactor failure)
Abnormal operating conditions
Restart
Restart
10.8.8 -
safety LED displays
The state of the safety relay can be visually checked through the device LED displays:
LED
Line supply
HPS sensor
Contactor feedbacks
Safety related
contacts
DEVICE
OUT
Green
Green
ON
Closed
Closed
(1)
Closed
Green
OFF
ON
Open
-
Open
OFF
OFF
Cross circuit or no power supply
(1) after power ON