Dwyer SCD - Manual (Page 5)

5
Figure 7: Retransmission
Output
10V or 20mA
0V or 4mA
PV Low PV High
Output slope
is negative
Output
PV Low PV High
PV PV
Output slope is positive
10V or 20mA
0V or 4mA
Alarm Output:
This controller provides 12 types of alarm outputs (See table below). When PV is higher or lower than SV, the
alarm output will be enabled.
SV Alarm Type Alarm Output Function
0 No Alarm Function Output is OFF
1
Deviation upper- and lower-limit:
This alarm output operates when PV value is higher than the setting
value SV+(AL-H) or lower than the setting value SV-(AL-L).
ON
OFF
AL-L SV AL-H
2
Deviation upper-limit:
This alarm output operates when PV value is higher than the setting
value SV+(AL-H).
ON
OFF
SV AL-H
3
Deviation lower-limit:
This alarm output operates when PV value is lower than the setting
value SV-(AL-L).
ON
OFF
AL-L SV
4
Reverse deviation upper- and lower-limit:
This alarm output operates when PV value is in the range of the setting
value SV+(AL-H) and the setting value SV-(AL-L).
ON
OFF
AL-L SV AL-H
5
Absolute value upper- and lower-limit:
This alarm output operates when PV value is higher than the setting
value AL-H or lower than the setting value AL-L.
ON
OFF
AL-L AL-H
6
Absolute value upper-limit:
This alarm output operates when PV value is higher than the setting
value AL-H.
ON
OFF
AL-H
7
Absolute value lower-limit:
This alarm output operates when PV value is lower than the setting
value AL-L.
ON
OFF
AL-L
8
Deviation upper- and lower-limit with standby sequence:
This alarm output operates when PV value reaches set point (SV
value) and the value is higher than the setting value SV+(AL-H) or
lower than the setting value SV-(AL-L).
ON
OFF
AL-L AL-H SV
9
Deviation upper-limit with standby sequence:
This alarm output operates when PV value reaches set point (SV
value) and the reached value is higher than the setting value
SV+(AL-H).
ON
OFF
SV AL-H
10
Deviation lower-limit with standby sequence:
This alarm output operates when PV value reaches the set point (SV
value) and the reached value is lower than the setting value SV-(AL-L).
ON
OFF
AL-L SV
11
Hysteresis upper-limit alarm output:
This alarm output operates if PV value is higher than the setting value
SV+(AL-H). This alarm output is OFF when PV value is lower than the
setting value SV+(AL-L).
ON
OFF
AL-H AL-L
12
Hysteresis lower-limit alarm output:
This alarm output operates if PV value is lower than the setting value
SV-(AL-H). This alarm output is OFF when PV value is higher than the
setting value SV-(AL-L).
ON
OFF
AL- H AL-L
Attention: AL-H and AL-L include AL1H, AL2H and AL1L, AL2L. When the 1 st group output is set to alarm output, AL1H (1024H) and AL1L
(1025H) will be used. When the 2 nd group output is set to alarm output, AL2H (1026H) and AL2L (1027H) will be used.