Troubleshooting
SITRANS FPS200
Operating Instructions, 08/2019, A5E46744245-AB
21
7
Troubleshooting
Pos. Description of faults
Possible cause
Primary element
1
No or too low differential
pressure
The primary element is not mounting in direction of the flow.
Connections of differential pressure between primary element
and transmitter are inverted (the inlet side of the primary
element is not connected with the plus side of the transmitter
and the outlet side of the primary element is not connected
with the minus side of the transmitter).
Initial shut-off plus and/or minus side is not opened.
Counterbalance valve is not closed.
Leakage in the differential pressure lines.
Upstream and downstream distances are too short.
Air pockets in the system/differential pressure lines or the
transmitter
(see measurements of steam and liquids).
Condensate in the system/differential pressure lines or the
transmitter
(see measurements of gases)
.
Primary element not mounted aligned centrally.
Condensate vessels not mounted on the same height (different
heights in the condensate columns, only at steam applications)
2
Exceeding scope of
measurement
Upstream and downstream distances are too short.
Initial shut-off in the differential pressure line at the minus side
is not opened.
Primary element not mounted aligned centrally.
Condensate vessels not mounted on the same height (different
heights in the condensate columns, only at steam applications).
3
Air pockets in the primary
element/pressure line and/or
transmitter
(in case of
measurement of liquids)
Default of the mounting of the primary element or the
transmitter.
Improper venting (see the operation instructions of the
differential pressure transmitter).
Differential pressure lines without grade
(in case of
measurement of steam and liquids).