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PHASE 3 - TRANSMITTER WIRING
4.
TRANSMITTER WIRING
4.1
PROTECTIVE GROUNDING
All transmitters are supplied with an external ground connection
for protective grounding.
Wire this ground connection marked with:
earth ground.
For a transmitter measuring loop an earth ground should
maintain a resistance of 5 ohms or less.
Use a heavy conductor, at least 15 AWG / 1,6 mm
WARNING ! - A protective grounding connection is
absolutely necessary to insure personnel protection, to
protect against surge (in case of installation of this option)
and to prevent explosions in potentially explosive
environment.
WARNING ! - In case the surge protection option is
present and the transmitter is installed in a Hazardous
area, the transmitter has to be power supplied from a
voltage source isolated from mains (galvanic separation).
Furthermore the potential equalization for the entire
powering cable must be guaranteed since the intrinsic
safety circuit of the transmitter is grounded.
4.2
ELECTRICAL CONNECTIONS
WARNING ! - Do NOT make electrical connections
unless the electrical code designation stamped on the
transmitter data plate agrees with the classification of the
area in which the transmitter is to be installed. Failure to
comply with this warning can result in fire or explosion.
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 EEx 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.
WARNING ! - Electrical shock can result in death or
serious injury. Avoid contact with the leads and terminals.
High voltage that may be present on leads can cause
electrical shock.
Follow these steps to wire the transmitter:
1. 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.
2. These connection ports have a 1/2 inch internal NPT
threads. Various adaptors and bushings can be fitted to
these threads to comply with plant wiring (conduit)
standards.
3. 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.
4. In case an Output meter is present it has to be removed by
pulling it out. Grip around the complete meter to avoid
pulling the cover from the base of the meter.
- 12 -
5. Run the cable through the cable gland and the open port.
6. Connect the positive lead to the + terminal, and the negative
lead to the – terminal.
✶
Note: Do not connect the power across the test
to a suitable
terminals. Power could damage the test diode in the test
connection.
Ø
2
7. 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 corrosive vapors
and gases.
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.
WARNING ! - Cable, cable gland and unused port
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