Connection Of The Analog Output (Hart) - ABB 2600T Series Operating Instruction

9.2

Connection of the analog output (HART)

1
2
Fig. 25: Electrical connections
1 Digital output | 2 Connection for Pt100 resistance thermometer | 3 Internal ground connection | 4 External ground connection |
5 Remote display | 6 Handheld terminal | 7 Power supply
Change from one to two columns
For connection of signal voltage / supply voltage twisted cable
with a conductor cross section of 18 ... 22 AWG / 0.8 ... 0.35
2
mm2 to to max. 1500 m length must be used. For longer
leads a greater cable cross section is required.
For shielded cables the cable shielding must only be placed on
one side (not on both sides). For the grounding on the
transmitter the inner terminal marked with
The output signal (4 ... 20 mA) and the power supply are
conducted via the same conductor pair. The transmitter
always works with a supply voltage between 10.5 and 42 V
DC.
For devices with "Ex ia" type of protection, "Intrinsic Safety"
(FM, CSA, and SAA approval) the supply voltage must not
exceed 30 V DC. In some countries the maximum supply
voltage is limited to lower values. The permissible supply
voltage is specified on the name plate on the top of the
transmitter.
The possible line length depends on the total capacity and the
total resistance and can be estimated based on the following
formula.
65 x 10 6 C
f
L = -
R x C
L = Line length in meters
R = Total resistance in Ohm
C = Line capacity
C = Maximum internal capacity in pF of the HART field
f
devices in the circuit
3
+ +
DIGI T AL OUTPUT
PWR /COMM.
USEWIRING RATED
5 °C MIN . ABOVE MAX 5 °C MIN ABOVE MAX .
AMBIENT T EMPE RATURE AMBIENT TEST
RTD E XT.
METER +
1 2 3 4
4
5
can also be used.
+ 10000
C
+
-
-
+M
7
%
Kent-Taylo r
Avoid cable installation, together with other power lines (with
inductive load, etc.), as well as the vicinity to large electrical
installations.
The HART handheld terminal can be connected to any
connection point in the circuit if a resistance of at least 250 Ω
is present in the circuit. If there is resistance less than 250
Ohm an additional resistor must be provided to enable
communication. The handheld terminal is connected between
the resistor and transmitter, not between the resistor and the
power supply.
266CRx, 266JRx, 266CSx, 266JSx | OI/266CXX/266JXX/HART-EN Rev. B 31
7
+
-
+
-
6
M10137