ABB 266 HART Series, Operating Instruction

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2600T Series Pressure transmitters | OI/266/HART-EN Rev. D 29
Important
With Category 3 transmitters for use in “Zone 2”, a qualified cable gland for this type of protection must be installed by the customer (see the section
“Hazardous Area Consideration”). An M20 x 1.5 threads is located in the electronics housing for this purpose.
For transmitters with “Flameproof enclosure” (Ex d) type of protection, the housing cover must be secured using the locking screw.
The screw plug that may have been supplied with the transmitter must be sealed at the plant using Molykote DX.
The installer assumes responsibility for any other type of sealing medium used.
At this point, we wish to draw your attention to the fact that increased force will be required to unscrew the housing cover after an interval of several
weeks.
This is not caused by the threads, but instead is due solely to the type of gasket.
Analogue output (HART) transmitter wiring
1 - Inner ground termination
point
2 - External ground termination
point
3 - Hand-held communicator
4 - Line load
5 - Remote indicator
6 - Power source
+
-
+
+
-
-
+M
-
Kent-Taylor
0
4
3
5 6
7
8
9
10
20
40
0
60
100 %
2
80
691HT
A B C
1
D E F
2
G H I
3
J K L
4
M N O
5
P Q R
6
S T U
7
V W X
8
Y Z #
9
@ % & /
0
+
-
PV
REVIE W SERIAL
LINK
TRI M
F1 F2 F3 F4
CONF
-
2 1
+
1
2
5
4
3
6
HART hand-held communicator may be connected at any wiring termination point in the loop, providing the minimum resistance
is 250 ohm. If this is less than 250 ohm, additional resistance should be added to allow communications. The handheld terminal
is connected between the resistor and transmitter, not between the resistor and power source.
Supply requirement
For signal/power connection use twisted, stranded pairs of wiring no 18 to 22 AWG / 0.8 to 0.35mm2 ø up to 5,000 feet (1500
meters). Longer loops require larger wire. If a shielded wire is used, the shield should be grounded only at one end, not both
ends. In case of wiring at transmitter end, use the terminal located inside the housing marked with the appropriate sign.
The 4 to 20 mA dc output signal and the dc power supply to the transmitter are carried from the same pairs of wires. The supply
voltage at the transmitter terminals must be between the limits of 10,5 and 42V dc.
For Ex ia and intrinsically safe (FM, CSA and SAA) approval power supply must not exceed 30 Vdc. In some countries the
maximum power supply voltage is limited to a lower value. For maximum power supply voltage please refer to the top
identification plate of the transmitter.
Figure 35: HART transmitter connection scheme