Heinrichs Messtechnik GmbH
Ex- Supplement operating manual
UMC4 with TM/TMU/TME/TMR/TM-SH
Page
11 of 31
4.3.3.1
Sensor Cable Pin Assignment
Pin Designation
Connection / Pin Assignment
Protection Type
Ex ia
Sensor circuit
Pick-Up1 +
1
x
Pick-Up1 -
2
x
Pick-Up2 +
3
x
Pick-Up2 -
4
x
TIk-
5
x
Temperature Sensor -
6
x
Temperature
7
x
TIk+
8
x
Exciter coil +
9
x
Exciter coil -
10
x
Schirm
Schirm
x
4.3.3.2
Cable Parameters
The operator is to comply in all cases with the applicable installation regulations such as EN 60079-14
“Electrical apparatus for explosive gas atmospheres
- Part 14: Electrical installations in hazardous areas
The operator is to comply in all cases with the applicable installation regulations such as EN 60079-14
“Electrical apparatus for explosive gas atmospheres
- Part 14: Electrical installations in hazardous areas
”.
Applicable guidelines pertaining to the interconnection of intrinsically safe circuits must also be observed.
The following maximum values apply to the cable mentioned above:
C
L
= 100 pF/m wire to wire
C
L
= 170 pF/m wire to shield
L
L
= 700 µH/km wire to wire
L
L
= 500 µH/km wire to shield
Warning
If a connecting cable other than the Heinrichs Messtechnik cable is used, the intrinsic safety of
the cable is to be validated using the cable’s nominal values
4.3.3.3
Equipotential bonding
Equipotential bonding between the sensor and transmitter is essential and must be established and
maintained. Connection points are provided on the outside of the sensor and transmitter for this
purpose.
