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8 Diagnosis, asset management and service
WIKA Operating Instructions - Differential pressure transmitter DPT-20
•
Evaluation of fault messages
•
Checking the output signal
•
Treatment of measurement errors
Further comprehensive diagnostics options are available with a PC/
notebook with PACTware and the suitable DTM. In many cases, the
reasons can be determined in this way and faults rectified.
Depending on the reason for the fault and the measures taken, the
steps described in chapter "
Setup
" must be carried out again or must
be checked for plausibility and completeness.
8.5 Replace process flanges
If required, the process flanges can be replaced by an identical type
by the user.
Required spare parts, depending on order specification:
•
Process flanges
•
Seals
•
Screws, nuts
Required tools:
•
Wrench SW 13
It is recommended that the work be carried out on a clean, level
surface, e.g. a workbench.
Caution:
There is a risk of injury due to residues of process media in the pro
-
cess flanges. Take suitable protective measures against this.
Proceed as follows:
1. Loosen hexagon head screws crosswise with wrench
2. Carefully remove the process flanges without damaging the dif
-
ferential pressure measuring cell
3. Lift O-ring seals out of the grooves of the process flanges using a
pointed tool
4. Clean O-ring grooves and separating diaphragms with a suitable
cleaner and soft cloth
Note:
Note additional cleaning for oil and grease-free version
Proceed as follows:
1. Insert new, undamaged O-ring seals into the grooves, check for
correct position
2. Mount process flanges carefully on the differential pressure
measuring cell, the seal must remain in the groove
3. Insert undamaged screws and nuts, screw together crosswise
4. First tighten with 8 Nm, then with 12 Nm
Reaction after fault recti-
fication
Preparations
Dismounting
Mounting
