WIKA DP-10 - Manual (Page 8)

8
GB
WIKA Operating Instructions Differential Pressure Transmitter
2333401 07/2009 GB/D/F/E
6. Calibration instructions
6. Calibration instructions
Please start the calibration only after a running-in period of approx.
30 - 60 minutes.
6.1 Zero point adjustment (Z)
For the zero point adjustment both process connections must be open. After pulling
off the rubber plugs at the instrument‘s front the output signal can be adjusted with
the zero potentiometer
(Z).
For the adjustment of pressure transmitters with absolute pressure measuring range
the process connection is to be connected to a pressure generator and an absolute
pressure reference via a T-piece. Subsequently an absolute pressure is generated for
which the output signal shall be: 0 V / 0 mA or 4 mA. Now the output signal can be
adjusted with the zero potentiometer
(Z).
6. Span adjustment (S)
For the span adjustment the nominal pressure must be connected via a T-piece from
the pressure generation to the pressure reference and the pressure channel.
The WIKA precision calibrator model CPC2000, which has a pressure generation
and a pressure reference, is excellently suitable for this task.
Pressure is to be connected to the “+” connection and vacuum to the “-” connec-
tion. Now the output signal may be adjusted with the span potentiometer
(S).
6.3 Adjustment of the alarm contacts
For the adjustment of the alarm contacts the reference pressure must be applied
at which the contact is supposed to close. This is accomplished with a pressure
generator which is connected to the pressure reference and the pressure channel via
a T-piece. Pressure is to be connected to the “+” connection and vacuum to the “-”
connection. The potentiometer of the switch point SP I or II must be adjusted until
the red LED above the respective potentiometer lights up, i.e. the switch value has
been reached and the contact closes.