4 | Commissioning
FISCHER Mess- und Regeltechnik GmbH
22/56
BA_EN_DA03_GKT_HLP_ATEX
4.3 Zero point correction
The differential pressure measuring units are set in the factory before delivery
so that they do not usually need to be adjusted at the assembly site. If this is
still necessary, proceed as follows:
• Depressurize the measuring chamber (+) und (-) side or only exert the exist-
ing static system pressure.
• Remove the closing screw The zero point correction screw is located be-
hind.
• Set the measurement value pointer to the scale zero point using the zero
point correction screw.
• Mount the closing screw
Without fluid filling
With fluid filling
Closing screw
11
1.2 x 7
Fig. 17:
Zero point correction screw
4.4 Switch point setting
There is an adjustment lock attached to the front pane of the measuring unit on
units with contact elements. This means that the contacts attached to the target
indicators can be set to any point along the scale.
To facilitate switching precision and the service life of the mechanical measur-
ing system, the switching points should lie between 10% and 90% of the meas-
uring range.
1
2
3
4
5
6
Fig. 18:
Switch point setting
1
Adjustment key
2
Adjusting lock
3
Axle
4
Drive arm
5
Set-point display
6
Actual value display
