6. Commissioning, operation / 7. Options and accessories
Switch point and zero point setting
The switch point and zero point setting is made by adjustment screws in the front,
which are accessible by loosening the plug screws.
By turning the adjustment screw using a screwdriver the desired zero point is set.
The switch points are set at the factory when the set points are given.
An assistant scale simplfies the setting of the switch point.
If an accurate switch point setting is required, a reference standard should be
used for the adjustment.
Plug screws must be refitted following switch or zero point setting,
as otherwise, the stated ingress protection will not be maintained.
6.3 Commissioning
During the commissioning process pressure surges must be avoided at all costs.
Open the shut-off valves slowly.
7. Options and accessories
7.1 4-way valve manifold
Isolation of the ⊕ and ⊖ process lines for removing or testing the measuring
■
instrument without interrupting the running process operation.
Protection of the instrument against
excessive overpressure loading, such as
in pressure tests and undefined operating
conditions (including intermittent shutdown).
Pressure compensation for zero point
■
checking with running processes, and avoi-
ding one-sided overpressure loading during
start-up and operation phases (with opened
pressure compensating valve).
Venting the measuring lines with liquid me-
■
dia and flushing of the measuring lines, in
order to remove contamination.
WIKA operating instructions DPGS40TA with component testing
Pressure
compensating valve
Shut-off valve
⊕ side
Shut-off valve
⊖ side
EN
Vent valve
27