TM
Page 25
Reference manual Foundation Fieldbus Control module
DOC.RM.QC34.E Rev: A
October, 2006
4.2.3.4 ZERO_PWR_COND
This parameter helps identifying whether the device
setup matches the actual mechanical configuration of
the actuator ;
- Fail-to-Close or Fail-to-Open for single acting
actuators.
This parameter idicates the position where the
actuator/valve unit will move to, when no power is
present (airpressure should be present for DA).
- The value is set during initialization and position
re-assignment and is valid for valve applications
which close after a clockwise (CW) rotation and
the operation of the valve may be Fail-to-Close or
Fail-to-Open.
- For applications which close after a counter clock
wise (CCW) rotation, the indication will be reversed
after initialization. This can be corrected by re-
assigning the end positions as decribed in §3.4.3.
4.2.3.5 BUTTONBOARD_ENABLE
The button bord can be set to:
- Enabled when in OOS (factory default)
- Never enabled
4.2.4 Diagnostic configuration
This section decribes the counter and timer
parameters. The describtion how to set alerts and
generate the recommended actions can be found in
§4.2.5.
4.2.4.1 Counters
Four counter parameters are available for counting
the cycles of the :
1 Control module
2 Actuator
3 Pneumatic module
4 Valve.
The Control (function) Module counter is the master
counter and is read only. The other three counters
can each be reset independently when required (e.g.
replacement).
These counter parameters have :
- a sub parameter which records the cycles.
- a sub parameter to set a limit value.
When one of the set limits is exceeded an alert and a
recommended action message will be generated as
per table 4.3 and as per alert setting ( see §4.2.5).
For the default setting and adjustable range, see
table 4.2. index 36, 37, 38 and 39.
4.2.4.2 Timers
There are 3 timers available in this device:
1 Time in position (TIME_IN_POSITION)
- Records the time since the last movement.
It is reset to zero when the power is switched off.
- In sub parameter TIME_IN_POSITION_HI_LIM,
a limit can be set.
2 Open travel time (OPEN_TRAVEL_TIME)
- Indicates the time between:
When pilot valve position is changed and when
the Open trip position reached.
- In parameters OPEN_TRAVEL_TIME_HI_LIM
and OPEN_TRAVEL_TIME_LO_LIM, high en
low limits can be set.
- Parameter OPEN_TRAVEL_TIME_AVG calcu-
lates the average stroke time of the last 30
strokes.
- In parameters OPEN_TRAVEL_AVG_HI_LIM
and OPEN_TRAVEL_AVG_LO_LIM, high en low
limits can be set.
3 Close travel time (CLOSE_TRAVEL_TIME)
- Indicates the time between:
When pilot valve position is changed and when
the Closed trip position reached.
- In sub parameter
CLOSE_TRAVEL_TIME_HI_LIM and
CLOSE_TRAVEL_TIME_LO_LIM, high en low
limits can be set.
- Parameter CLOSE_TRAVEL_TIME_AVG
calculates the average stroke time of the last 30
strokes.
- In parameters CLOSE_TRAVEL_AVG_HI_LIM
and CLOSE_TRAVEL_AVG_LO_LIM, high en
low limits can be set.
When the limits of the above timers are exceeded,
and the alerts are enabled, alerts and recommended
action messages will be generated as per table 4.3
and as per alert setting (see §4.2.5).
