KROHNE BM 70 M User Manual
Page 28
28
BM 70 M
7.6 Electrical
connection
The electrical connection for supply power and signal inputs/outputs is made in the terminal
compartment (Ex-e) of the signal converter. Observe requirements specified in VDE 165, and
consult the safety advice given in Section 9.4.
In the BM 70 M version with intrinsically safe signal output, only certified
intrinsically safe equipment may be connected to the blue terminals, even if the
device is not operated in the hazardous area!
Terminals
conductor cross-section 0.5 - 2.5 mm² (solid conductor: max.
4mm²)
PE safety conductor and/or
FE functional ground
U-clamp terminal (max. 4 mm² conductor cross-section)
(see also terminal assignments below and in Sect. 9.4)
Cable entries
3x M25x1.5 (with standard cable gland: cable clamping area =
9-16 mm)
Signal cable shielding
required for RS 485 line
recommended for current output when line lengths > 100 m (350ft)
"Ex" equipotential bonding:
U-clamp terminal (max. 4 mm² conductor cross-section) on "neck"
of signal converter
Rated temperature of power cables:
Version
Max. flange temperature
Rated temperature of power cables
w/o high temperature
≤
100°C/212°F
70°C/158°F
distance piece
> 100°C/212°F
80°C/176°F
with high temperature
≤
200°C/392°F
70°C/158°F
distance piece
> 200°C/392°F
80°C/176°F
Terminal assignment:
Supply power
Connections for 115/230 V AC
Connections for 24 V DC/AC (any polarity)
Connection of an FE functional ground is not
mandatory
N
L
PE
~
~
N
L
Inputs/Outputs
1
2
+(-)
-(+)
24V DC
24V AC
FE
~
~
Inputs/Outputs