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VCP63MA4-200508
4.2.2
Adjustment On Zero Reference Pressure
For this adjustment a pressure below 1.0x10
-2
mbar has to be applied.
To achieve optimum results of the adjustment we recommend
a warm-up of at least 5 minutes at the appropriate calibration
pressure before any adjustment. Important: be sure to use
suitable reference gauges only!
For adjustment first remove the rubber caps from the "adj" and "set" button (1),
then push the "set" button by means of a screw driver or other suitable tool (2).
Now a current is provided at the signal output which corresponds to the actual
zero reference pressure (ex works: 3.8 mA for "ur" pressure underrange).
By pushing the "adj" button several times you can now increment this value to
maximal 1.0x10
-2
mbar (3) according to the pressure-current relation in
chapter 4.1. Then the output again starts at the current signal for "ur". When the
output is correctly adjusted to the actual reference pressure, the adjustment
procedure is carried out automatically after 5s. Further the new reference
pressure for zero adjustment is saved. From now on zero adjustment as
described in chapter 4.2.1 (push "adj" button at zero pressure) will result in an
adjustment on the saved reference pressure. Insert the rubber caps again.
When the "set" button is pushed without further action you can check the
currently saved zero reference pressure. The transducer then outputs the
corresponding signal for 5s, no adjustment is carried out.
