DANGER!
Improper wiring in a hazardous environment can cause an explosion. Install the meter only in
an area that complies with the hazardous classification tag on the meter.
RS-485 output and cable entity parameters
Table 3-5:
Cable parameters for intrinsically safe circuit (linear)
Voltage (U
i
)
17.22 VDC
Current (I
i
)
484 mA
Maximum capacitance (C
i
)
1 nF
Maximum inductance (L
i
)
Negligible
Cable parameters for Ex ib IIB, Ex ib IIC
Voltage (U
o
)
9.51 VDC
Current (instantaneous) (I
o
)
480 mA
Current (steady state) (I)
106 mA
Power (P
o
)
786 mW
Internal resistance (R
i
)
19.8
Ω
Cable parameters for Group IIC
Maximum external capacitance (C
o
)
85 nF
Maximum external inductance (L
o
)
25 µH
Maximum external inductance/resistance ratio
(L
o
/R
o
)
31.1 µH/
Ω
Cable parameters for Group IIB
Maximum external capacitance (C
o
)
660 nF
Maximum external inductance (L
o
)
260 µH
Maximum external inductance/resistance ratio
(L
o
/R
o
)
124.4 µH/
Ω
3.4.2
Prepare the 4-wire cable
Important
For user-supplied cable glands, the gland must be capable of terminating the drain wires.
Note
If you are installing unshielded cable in continuous metallic conduit with 360º termination shielding,
you only need to prepare the cable – you do not need to perform the shielding procedure.
Wiring
Installation Manual
29