KROHNE IFC 090 Converter EN - Manual (Page 47)

6/2
Stable signal outputs when measuring tube empty 6.3
Output signals can be stabilized to values as for “zero” flow to prevent random output signals
when the measuring tube is empty or when the electrodes are not wetted in the event the
measuring tube is partially full.
- Display: 0
- Current output: 0 or 4 mA, see setting in Fct. 1.05
- Pulse output: no pulses (= 0 Hz), see setting in Fct. 1.06
Precondition: electrical conductivity of product:
≥
200 µS/cm,
≥
500 µS/cm for meter sizes DN 2.5 - 15 and 1 / 10 ” - 1 / 2 ”
Changes on amplifier PCB, see illustration in Sect. 8.9.
Switch off power source before opening the housing!
1) Unscrew cover from the terminal compartment using the special wrench. Pull off the
two plugs for supply power (3-pin) and outputs/inputs (6-pin).
2) Unscrew cover from the electronic compartment using the special wrench.
3) If provided, remove display unit. For this purpose, detach the two screws R and fold
display unit to the side, see illustration in Sect. 8.5.
4) Carefully pull off the blue 9-pin plug X1/X4 (forming the connection to the primary head).
5) Detach the 2 recessed head screws Q and carefully remove the electronic unit.
6) Join the two “semicircles” of points S1 and S3 on the amplifier board with tin solder,
see illustration in Sect. 8.9.
7) Reassemble in reverse order, points 5) - 2) above.
8) Switch on power.
9) Check setting of the low-flow cutoff SMU, Fct. 1.03, and reset if necessary:
L.F.CUTOFF switched on, range:
Operator control:
Display Version: IFC 090
/ D, see Sect. 4 and 5.3, Fct. 1.03
Basic Version: IFC 090 / B, see Sect. 6.2.
10) After checking and/or resetting, replace the cover on the electronic compartment and
tighten using the special wrench.
NOTE: The screw thread and gasket of the housing cover should be well greased at
all times, always check for signs of damage and never allow dirt to accumulate.
Replace defective gasket immediately.
Full scale range Q
100%
Cutoff ...... values
... OFF ... ... ON ...
> 3 m/s > 10 ft/s > 0 2 % 1 %
1 - 3 m/s 3 -10 ft/s > 0 6 % 4 %
< 1 m/s < 0 3 ft/s >10 % 8 %