Functional description
5
gas-lab
Q1
Page 67
The M-switch is activated via an assigned digital input. It cannot be set via the
operator panel for safety reasons.
Status and signalling reactions of
single
messages remain unaffected by the M-
switch. Single messages are suppressed via the disabling mechanism explained
above.
In addition to the above-mentioned messages a message named
Main signaller
is also available. It usually triggers a hooter if being routed to an output. An
additional acceptance input is assigned to the main signaller.
The main signaller may include any number of groups.
It starts operating when a message arrives that belongs to one of the involved
groups, and it ends upon acceptance, no matter whether or not messages are
still pending. The acceptance can be implemented via the digital input assigned
to the main signaller. Besides, if all groups are accepted via the operator panel,
the main signaller is also accepted. It starts operating again when the next
involved message arrives.
The following illustration shows the behaviour of the main signaller in connection
with the acceptance (in case of one involved group):
Group
Single message M1
Single message M2
Acceptance
Acceptance
Main signaller
message