Siemens SITRANS P500, Operating Instructions Manual, Page: 184 / 238

Commissioning
8.3 Differential pressure and flow rate
SITRANS P500 with HART
184
Operating Instructions, 12/2014, A5E02344528-09
WARNING
Hot vapor
Danger of injury.
You can briefly open the drain valves
⑦
to clean the line. Hot vapor can escape in the
process.
•
Only open the drain valves
⑦
briefly, and close them again before vapor escapes.
To commission the pressure transmitter for vapor, proceed as follows:
1.
Open both the shut-off valves
⑥
at the pressure tapping point.
2. Open the stabilizing valve
②
.
3. Wait until the steam in the differential pressure lines
⑤
and in the equalizing vessels
⑧
has condensed.
4. Open the differential pressure valve
③
and the vent valve on the positive side of the
pressure transmitter
①
slightly, until air-free condensate escapes.
5. Close the vent valve.
6. Open the vent valve on the negative side of the pressure transmitter
①
slightly, until
condensate escapes without bubbles.
7. Close the differential pressure valve
③
.
8. Open the differential pressure valve
④
slightly, until condensate escapes without
bubbles, then close it.
9. Close the vent valve on the negative side
①
.
10.Open the differential pressure valve
③
by rotating it in ½ turn.
11.Check and correct, if necessary, the zero point (4 mA) when the start of scale value is
0 kPa.
The result is only error-free if the differential pressure lines
⑤
have equally high
condensate columns with the same temperature. The zero calibration must be repeated if
required if these conditions are fulfilled.
12.Close the stabilizing valve
②
.
13.Fully open the differential pressure valves
③
and
④
.
14.You can briefly open the drain valves
⑦
to clean the line.
15.Close the drain valve
⑦
before vapor escapes.