Cashco Siemens PS2 I/P User Manual
Page 87
Operation
87
SIPART PS2 Manual
A5E00074631-01
Alarm function
The actuator can report the exceeding (max.) or dropping below (min)
of a specified stroke or angle of rotation. The response of the alarms
(limit contacts) is related to the MPOS-scaling (see figure 4-9, page
85). The alarms are reported by the alarm module (order no.
6DR4004-6A or -8A). In addition the alarms can be read out through
the HART interface (optional).
The direction of action of the digital outputs can be adapted from high
active to low active sequence systems.
Response threshold alarm 1
and
Response threshold alarm 2
The alarm thresholds are related to the mechanical path (MPOS-scale).
Function of the fault message output
The fault message output serves as a group message for following
faults:
-
Control error (e.g. by actuator fault, valve fault, compressed air fai-
lure) with the parameters “48. TIM” and “49. LIM”
-
Positioner not in automatic mode
-
Digital input activated (see parameter “42.BIN1” and “43.BIN2”)
-
Exceeding of a limit value (e.g. way integral or valve seat, see para-
meter 50 to 54)
It also responds at:
-
Power failure
-
Processor fault
The direction of action of the digital outputs can be adapted from high
active to low active sequence systems.
Monitoring time for setting the fault messages
The set value (s) serves as a specification for the time within which the
positioner must have reached the controlled state. The corresponding
response threshold is specified with “49. LIM”.
The fault message output is set on exceeding the set time.
Response threshold of the fault message
Here a value (%) can be set for the permissible variable of control error
for releasing the fault message.
If the parameters “48. TIM” and “49. LIM” are both set to ”Auto”, the
fault message is set if the short step zone is not reached within a
certain time. This time is 5 times the initialization travel time within 5 to
95% of the actuating path and 10 times this time outside 10 to 90% of
the actuating path.
44.AFCT
45.A1
46.A2
47. FCT
48. TIM
49. LIM