KROHNE UFM 3030 Service EN - Manual (Page 43)

UFM 3030 43
8.3 Change of power supply fuse
For continued fire protection or protection against other damage, replace with a fuse
specified in this handbook.
Before demounting the electronics from the housing disconnect instrument from the
mains. Always switch off power source before commencing work!
Only applicable for the 100-240 Vac power supply.
The 24Vac/dc power supply is provided with an auto restoring electronic fuse that does not need
replacement.
The main fuse is mounted on the power board of the
electronics. If this fuse is blown there will be no reading
on the display and the backlight will be off. The fuse
should not blow normally unless a problem has
developed in the instrument. Try to determine and
correct cause of the blown fuse, then replace only with
a fuse of the correct rating and type. The main fuse
can only be reached by demounting the complete
electronics from the housing.
1. Use the special wrench to remove the cover from the front compartment.
2. Remove screws A, fold display board to side, and remove plug B (ribbon cable, display board).
3. Power fuse F1 is now accessible. It must be replaced by the same type of fuse as specified
below.
4. Reassemble in reverse order.
Fuse specification
To avoid unsafe situations replace a blown main fuse only with a type with the following
specifications:
Dimensions
5 x 20 mm (miniature cartridge fuse)
Rated current 800 mA
Characteristic Time Delay (T)
Rated voltage 250 V
Breaking capacity 1500 A (ceramic body fuse, high breaking capacity)
Standard IEC 60127-2
Approvals UL and OR CSA, VDE, SEMKO, BSI