ABB 266 HART Series, Руководство по эксплуатации

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30 OI/266/HART-EN Rev. D | 2600T Series Pressure transmitters
266 Models - HART
1 2
3
The actual possible line length of the electrical circuit depends on the total capacitance and resistance, and can be estimated
using the following formula:
65 x 10
6
R x C
L =
C
f
+ 10000
C
–
Where:
L = Line length in meters
R = Total resistance in Ω (ohms)
C = Line capacitance in pF/m
Cf = Maximum internal capacitance of the HART field devices
located in the circuit, in pF
Avoid routing cables with other electrical cables (with inductive load, etc.) or near large electrical equipment.
Wiring procedure
Follow these steps to wire the transmitter:
– Remove the temporary plastic cap from one of the two electrical connection ports located at both sides in the upper part of
the transmitter housing.
– These connection ports may have a 1/2 inch internal NPT or M20 threads. Various adaptors and bushings can be fitted to
these threads to comply with plant wiring (conduit) standards.
– Remove the housing cover of the “field terminals” side. See the indication on the label on top of the housing. In an Explosion-
Proof/Flame-Proof installation, do not remove the transmitter covers when power is applied to the unit.
– Run the cable through the cable gland and the open port.
– Connect the positive lead to the + terminal, and the negative lead to the – terminal.
– Plug and seal the electrical ports. Make sure that when the installation has been completed, the electrical ports are properly
sealed against entry of rain and/or corrosive vapors and gases.
– If applicable, install wiring with a drip loop. Arrange the drip loop so the bottom is lower than the conduit connections and the
transmitter housing.
– Put back the housing cover, turn it to seat O-ring into the housing and then continue to hand tighten until the cover contacts
the housing metal-to-metal. In Ex-d (Explosion Proof) installation, lock the cover rotation by turning the set nut (use the 2mm
Allen key supplied with the instrument).
Electrical connection via connectors
Harting connector (HART output versions) on DIN housing
1 - DIN Housing with Harting angle connector
2 - DIN Housing with Harting straight connector
3 - Harting Han 8D socket insert for mating plug supplied (view of sockets)
Warning - General risks
Cable, cable gland and unused port plug must be in accordance with the intended type of protection (e.g. intrinsically safe, explosion proof, etc.) and
degree of protection (e.g. IP6x according to IEC EN 60529 or NEMA 4x). See also the addendum for “EX SAFETY” ASPECTS AND “IP” PROTECTION. In
particular, for explosion proof installation, remove the red temporary plastic cap and plug the unused opening with a plug certified for explosion
containment
Figure 36: Harting HAN straight and angle connection connectors