Siemens SITRANS FP 7ME17.8, Operating Instructions Manual, Page: 18 / 23

Commissioning
SITRANS FPS200
18
Operating Instructions, 08/2019, A5E46744245-AB
6 Commissioning
6.1 Usage of further components
6.1.1 Condensate vessels (for steam applications, if included in the scope of delivery)
Usage
Usage of condensate vessels is recommended for gaseous media that turn liquid in the differential pressure lines
when cooling off. This is the case especially for steam. Depending on pressure and temperature, it may occur as
well with other media (for example alcohols).
Function, installation and commissioning
During installation, observe that the two condensate vessels are at the same height; otherwise, zero-point
calibration is difficult.
The condensate vessels, including the differential pressure lines to the differential pressure transmitter, must be
filled with water/condensate before commissioning the measurement. They may be filled in different manners:
•
Through fill sockets at the condensate vessels (if present).
•
Through the condensate drain valves or vent of the differential pressure transmitter.
For this, the differential pressure lines must be connected to the water supply, e.g. by a hose screw connection.
After commissioning of the steam line, wait until the differential pressure lines and condensate vessels have filled
with condensation on their own. All valves at the valve block must be closed for this.
Attention!
Overheating of the differential pressure transmitter must be avoided. Depending on steam temperature, the
temperature at the valve block must be monitored. Close the shut off valves in the differential pressure lines when
there is any danger of overheating.
The condensate vessels ensure that the differential pressure lines are always filled with water and that no hot steam
can reach the diaphragm of the differential pressure transmitter. Condensing steam ensures that the water column
is retained. Excess condensation flows back and evaporates again. Using condensate vessels in steam applications
considerably reduces fluctuations of the water column. The even measuring signal and increased zero stability
warrant even measuring accuracy. The water column transfers the effective pressure DP to the transmitter.
Note!
In any case, wait for a stable condition to be reached after filling and commissioning of the steel supply, before
setting the zero point.