RTK LN1000, Руководство пользователя

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LN1000 IS Annunciator
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SW FUNCTION UP DOWN
1 GTA Output mode Alarm sequence Field contact
2 GTB Output mode Alarm sequence Channel audible
3 GT Output Polarity Low High
4 B1 Field Contact Group Yes No
5 Field contact input delay No Yes
6 Field contact mode Normally closed Normally open
7 First-up group number bit 2 see first up group table
8 First-up group number bit 1 see first up group table
9 First-up group number bit 0 see first up group table
10 Alarm sequence number bit 2 see alarm sequence table
11 Alarm sequence number bit 1 see alarm sequence table
12 Alarm sequence number bit 0 see alarm sequence table
Group Trip Outputs
Each alarm channel has a two Group Trip Outputs (GTA and GTB).
These are solid state open collector outputs that can be used to trip or control further parts of
the plant either in the safe or hazardous area. There are a number of user selectable
features on both these outputs as shown below:-
The outputs can be configured to be active high or active low by using DIL switch 3. This DIL
switch will change the operation of both outputs (GTA and GTB) on that alarm channel.
Group Trip A
There are two choices for this output, to follow the alarm sequence or the field contact.
When configured to follow the field contact the output will trigger when the channel is in the
alarm state, independent of whether N/O or N/C alarm contacts are being used. When
configured to follow the alarm sequence the output will remain active until the alarm channel
has returned to normal AND the annunciator reset.
Group Trip B
Again there are two choices for the second output GTB, either to follow the alarm sequence
or the channel audible.
The method of following the alarm sequence is exactly as described above. When set to
follow the audible it is driven whenever a channel goes into alarm and goes off when the unit
is silenced or acknowledged. This is useful if the operator needs to be aware of a particular
alarm or group of alarms using a different audible tone.
B1 Field Contact Group
The B1 Output is a common output on the Sequence Card.
When this output is set to follow the field contacts it is possible to select each alarm channel
to be in this group or not. The Group is described as the "Field Contact Group". This is useful
to link a group of channels to a common output to trigger some additional action or indication.