Service manual

B-8
Alarm sequence 3
B
Alarm handling
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Alarm sequence 3
Alarm states in
sequence 3
The following figure shows the various states in alarm sequence 3:
Behavior Alarm sequence 3 has no attention function. You just have 5 independent alarm
relays and 2 alarm LEDs. In sequence 3 the A alarm LED lights and the A relay
becomes active when there is an active A alarm. When there is an active B C, D or E
alarm the B alarm LED lights and the relevant B, C, D or E relay gets active.
Alarm sequence 3
characteristics
The following table shows the characteristics of alarm sequence 3:
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Which alarm sequence do I select?
To select the most
suitable alarm
sequence
Use the following rules when you select the alarm sequence:
• If you have a national or organizational standard for alarm sequences, select that.
• If you want a Receiving Attention function, select alarm sequence 1 or 2. Other-
wise select alarm sequence 3.
• If you want to have a relay indication of cleared alarms with attention, select
sequence 1.
• If you want relay indication of all active alarms no matter whether they have atten-
tion or not, select sequence 2.
0
No Alarm
1
Alarm
Alarm active
Alarm inactive
Alarm Sequence 3
No attention.
Alarm LED A = A alarm(s) in state 1
Alarm LED B = B alarm(s) in state 1
Rec. Attn. LED = no use
A relay = A alarm(s) in state 1
B relay = B alarm(s) in state 1
C relay = C alarm(s) in state 1
D relay = D alarm(s) in state 1
E relay = E alarm(s) in state 1
Alarm sequence 3 characteristics
5 independent relays Yes
No attention function Yes