Siemens 7MF4033 series, Руководство пользователя

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Post-Installation Test UMSITRPDS3-1
November 2010
5-8
5.5.2 Differential Pressure and Flow
Differential pressure and flow transmitters can be commissioned using the following methods.
WARNING
Process material can be hazardous to people and harmful to equipment. Serious
injury or considerable material damage may result if:
•
The vent valve and/or the sealing screw are missing or are not sufficiently
tight.
•
The valves are operated wrongly or improperly.
In the case of hot process liquid or gas, the individual operating steps must be
performed in rapid succession. Otherwise, the valves and the transmitter may be
over heated leading to damage.
5.5.2.1 Measuring Gases
Operate the shutoff valves in the following order. Refer to Figure 5-4 to identify the valves used in the
procedure.
1. Close all valves.
2. Open both shutoff valves (5) at the pressure taps.
3. Open the compensation valve (2).
4. Open one active pressure valve (3A or 3B).
5. Check and correct zero (4 mA) if necessary at zero mbar.
6. Close the compensation valve (2).
7. Open the other active pressure valve (3A or 3B).