Thyracont SP363, Operating Instructions Manual

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4.2 Readjustment
The transducer is adjusted ex works with 24 V voltage supply in upright position,
flange to the bottom. Other orientation, operation under different climatic conditi-
ons, extreme temperature changes, ageing or contamination can result in the need
for readjustment.
To achieve optimum results of the adjustment we recommend to
consider a warm-up of at least 15 minutes at the appropriate cali-
bration pressure before any adjustment.
The transducer can be digitally readjusted by means of the »up« and »down« pu-
shbuttons. Therefore the pressure reading of the VSR must be above 800 mbar or
below 3 mbar. Best practice is an adjustment at the measuring range limits.
For zero adjustment actual pressure should be less than
5.0x10
-6
mbar.
In all other cases a reference pressure reading of a standard gauge
will be required.
For adjustment first remove the rubber caps from both pushbuttons (1). Then -
by means of a screwdriver or other suitable tool- press one of the pushbuttons
(2), until the status LED starts flashing quickly in orange. After 3 s without further
keystroke the LED turns flashing slowly and the transducer is ready for adjustment.
Use the »up« and »down« keys to increment or decrement the transducer’s output
signal (3), until the pressure reading corresponds to the related reference pressu-
re. The output signal of the VSR must equal 3.800 mA (under range) when zero
pressure is applied or otherwise be set according to the formula of chapter 4.1 in
dependence of the applied reference pressure. After 10 s without further keystroke
the adjustment will be finished and stored. Now insert the rubber cap again.
VSR-4-20 mA-210805