KROHNE BM 70 M Series, Installation And Operating Instructions Manual

Page: 72 / 110

72 BM 70 M
9.2 Fuses
Device-internal fuses for power:
24 V DC/ AC*
T 1.25 A
115 V AC** T 315 mA
230 V AC** T 160 mA
* Terminals 1 and 2 are both fuse-protected.
** Only connection L (for TN system) is fuse-protected; optionally also both connections N and L
(for IT system), see Sect. 9.3.
Location of fuses on the "line" board and replacement of fuses: see Sect. 9.3.
In accordance with operative regulations, it may be necessary to provide additional fuse
protection when installing the system.
Recommended line fuse protection:
24 V DC/ AC min. T 2 A
115 V AC min. T 0.5 A
230 V AC min. T 0.25 A
9.3 Changeover of operating voltage and replacement of fuses
Attention:
Always switch off power source before commencing work!
Hazardous-duty systems:
Before opening the "flameproof enclosure" (large cover on the signal converter) in the hazardous
area, make absolutely certain that there is no explosion hazard. Allow the prescribed waiting time
of 10 minutes to elapse first!
1. Unscrew sunshade SD, if fitted.
2. Detach safety lock SV using Allen key (size 4 mm).
3. Remove cover DE from the electronic compartment
flameproof enclosure) with the supplied special
wrench
4.1 Replacement of power fuse(s)
Location of fuses: see drawings below. Use only the specified types.
4.2 Changeover of operating voltage (AC Version only)
Through a different orientation of the voltage selector switch on the "line" board you can
switch over between 115 V AC (85-127V) and 230 V AC (170-254V). For this purpose, pull
the plug next to the fuse holders up and out (see drawing below), turn it 180° and plug it
back into the holder. Also change the two fuses F2 and F3 to suit the selected voltage.
Do not forget to alter the voltage information on the signal converter nameplate and in the
terminal compartment!