WIKA HP-2 User Manual

Page 14

WIKA operating instructions pressure transmitter, model HP-2

11379180.03 09/2013 GB/D/F/E

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 transmitter.

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

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