KROHNE ALTOFLUX IFM 4080 K EEx EN User Manual

Page 18

Figure 11: IFC 090-EEx electronics unit (115/230 Vac version).

4.1.2 Replacement of power fuse(s)

The power fuse(s) of the different IFC 090…-EEx electronics units (regular or MODIS) have
a different rating and are located on slightly different locations on the power supply printed
circuit board. Only the power fuse on the 100…230 Vac power supply version of the regular
IFC 090-EEx electronics unit can be reached without removing the complete unit out of the
housing (only the display unit has to be unscrewed).

Regular IFC 090-EEx with 24 Vac/dc power supply

Before commencing work,

note the instructions in Section 3.1 ("Before opening")

Then continue as follows:

1. Remove the cover of the electronics compartment.
2. Unscrew the two screws marked with A of the display unit and turn it carefully aside.
3. Disconnect the 2-pole field circuit connector (item B) as well as the 3-pole electrode

circuit connector (item C). See figure 11 above.

4. Unscrew the two mounting screws D of the electronics unit and screw SE, which fixes the

copper earth strip to the integrated aluminum dividing wall at the back of the electronics
compartment. Use a screwdriver with a long shaft (

≥

200 mm) like type Philips No. 2 for

screw SE. Then take out the electronics unit, but be careful with the connecting cables,
so that they do not get damaged.

5. The defective power fuse(s) F1 and/or F2 (see figure 12 on the next page) can be

replaced now. The 24 Vac/dc power supply uses two sub-miniature fuses type TR 5 that
are rated T1.25A in accordance with IEC 127-3 publication (part No. 5.09080.00.00).

6. Reassemble in reverse order (points 3 through 1).

Note the instructions of section 3.1 ("After opening") during reassembling.

Display unit

(back side)

Flat cable of

display unit

Copper earth strip

B: Field circuit
connector (2-pole)

C: Electrode circuit
connector (3-pole)