- 15 -
6.
In general, the curve shapes do not change if the zero and span values are set properly. If the
instrument is being re-ranged, simply use a new full scale value and normalize the output
curve to 100%. If extreme nonlinearities exist, such as that of a laminar to turbulent flow
regime transition, a new curve will need to be constructed. Furthermore, if a transition region
exists and the instrument must operate over a range of temperatures, several curves must be
constructed at fixed temperature steps throughout the temperature range to assure best
accuracy.
4.3 SPARE PARTS
There are no normally recommended spare parts to stock. The transducer and electronics boards are
a matched set and therefore are not interchangeable with others. Should a spare be needed, a complete
unit should be ordered and stocked. Spare fuses are ½A fast acting Wickmann fuse, part number
3730500041 or equivalent for 115/230 Vac usage and 1A slow blow Wickmann fuse part number
3741100041 for 24V usage.
4.4 TROUBLE SHOOTING
TABLE III. TROUBLE SHOOTING GUIDE
OBSERVATION
PROBABLE CAUSE
REM EDY
Flow trip level continually drifting
downward with constant flow.
Coating forming on wetted surface of
transducer.
1.
Clean transducer periodically.
2.
Adjust span potentiometer
clockwise until layer build-up
stabilizes.
After flow switch has been operating
properly:
Relay incorrectly trips with flow
above or below trip level and cannot
be adjusted using instructions in
SECTION 3.2
.
1.
Dirty electrical contacts.
2.
Bad electronic component
1.
Inspect electronics module and
its socket for corrosion. Clean
and replace.
2.
Contact factory.
Relay cannot be made to trip by
adjusting trip adjustment
potentiometer(s).
1.
Flow rate out of range of
instrument.
2.
Flow media change.
1.
Refer to SECTION 4.2 on
calibration to re-range the
instrument.
2.
Contact factory.
Relay trips on and off, or flow signal
is very noisy but flow is constant and
steady.
1.
Flow noise is being amplified
by fast response circuitry.
2.
Instrument has been readjusted
or instrument is defective.
1.
M ove time response jumper to
“SLOW .”
2.
Contact factory.
LED is not lit and relay stays in
alarm condition (N.C. contact is
made).
1.
No power to electronics.
2.
Blown fuse.
1.
Check incoming voltage.
2.
Replace fuse with appropriate
ampere and time delay rating.
3.
Return to factory.
