Adjustment Of Zero Point And Span - WIKA HP-2 Manual De Instrucciones

7. Adjustment of zero point and span

7. Adjustment of zero point and span
Only adjust the span-setting potentiometer if calibration equipment is avail-
able which has at least three times the accuracy of the pressure sensor.
EN
7.1 Preparation (figure A)
To gain access to the potentiometers, open the instru-
ment as follows:
Disconnect the electrical connection  from the
■
instrument.
Remove the clamping nut .
■
Carefully pull the instrument connector  from the
■
instrument.
Connect the instrument connector  to the power
■
supply and a display unit (e.g. ammeter, voltmeter)
according to the connection diagram.
7.2 Adjustment of zero point (figure B)
Go to the start of the measuring range.
■
Using potentiometer "Z", adjust the minimum output
■
signal (e.g. 4 mA).
7.3 Setting the span (figure B)
Go to the end of the measuring range.
■
Using potentiometer "S", adjust the maximum output
■
signal (e.g. 20 mA).
Check the zero point and if there is any deviation,
■
re-adjust it.
Repeat the procedure until the zero point and the
■
span are set correctly.
7.4 Finish the adjustment (figure A)
Disconnect the instrument connector  from the power supply and the display unit.
■
Carefully push the instrument connector  onto the instrument, without damaging the
■
wires or the seals. The seals must be clean and undamaged in order to guarantee the
given ingress protection.
Tighten the clamping nut .
■
After the adjustment, check that the system is functioning correctly.
Recommended recalibration cycle: Half-yearly
14 WIKA operating instructions pressure sensor, model HP-2
A



B