Endress+Hauser dosimass, Руководство по эксплуатации

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Commissioning Dosimass
22 Hauser
6.3.1 Preconditions for a zero point adjustment
Note the following before you perform a zero point adjustment:
• A zero point adjustment can be performed only with fluids that contain no gas or solid contents.
• A zero point adjustment is performed with the measuring tubes completely filled and at zero flow
(v = 0 m/s (0 ft/s)). This can be achieved, for example, with shutoff valves upstream and/or
downstream of the sensor or by using existing valves and gates (

å
15).
– Normal operation

valves 1 and 2 open
– Zero point adjustment with pump pressure

valve 1 open / valve 2 closed
– Zero point adjustment without pump pressure

valve 1 closed / valve 2 open
A0008558
Fig. 15: Zero point adjustment and shutoff valves
6.3.2 Performing a zero point adjustment
1. Operate the system until operating conditions have settled.
2. Stop the flow (v = 0 m/s (0 ft/s)).
3. Check the shutoff valves for leaks.
4. Check that operating pressure is correct.
5. Now perform the calibration via the ZERO POINT ADJUST. function (

ä
49).
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2