MAN-0148, Rev 1
11
March 2016
SECTION 2: Wiring and installation
2.1 Field Installation
Warning
Wiring codes and regulations may vary. ATEX requires that supply connection wiring must be rated at
least 5°C above the maximum ambient temperature of 85 °C. Wiring must comply with all applicable regulations relating to
the installation of electrical equipment in a hazardous area and is the responsibility of the installer. If in doubt, consult
qualified personnel before wiring the system.
Warning
Do not open the transmitter enclosure in a classified area (Do not open when an explosive atmosphere
may be present).
Guidelines
•
The safety ground connection of the transmitter is a Green screw found in the enclosure. See Figure 4 for
Ground screw location.
Note:
The electronics module has to be removed to access Ground screw. Follow steps
1-7 under Section ‘1.2.3 Rotating electronics module relative to enclosure and conduit entries’, when
removing electronics module.
•
If the 4-20mA signal is not used, connect a jumper between the 4 – 20mA terminal and the Common terminal
to allow analog current levels to be monitored at the Test Jacks on the faceplate.
The use of shielded cable is highly recommended for signal, input, output and power wires. Refer to Section ‘2.1.2 Cable
choice and guidelines’ for recommended cable to help eliminate interference caused by extraneous electrical or
electromagnetic ‘noise’. To reduce the effect of Radio Frequency signals on the equipment, follow the recommendations
listed under Section ‘2.1.2 Cable choice and guidelines’.
In applications where wiring is installed in conduit, conduit must not be used for wiring to any other electrical equipment.
For effective communication, Net Safety limits sensor separation to 2000 feet using 16AWG wires.
Modbus RS-485 connection 2-wire mode, multipoint serial line available. Up to 247 addresses allowed.
When developing a RS-485 chain of devices, the last device in the chain requires an end of line termination resistor (120
Ohms).
Transmitter connector terminals accommodate wire from 14 to 20 AWG wires.
2.1.1 Seals
Warning
The use of conduit wiring seals is recommended to protect the system against water ingression, and
equipment should be installed according to local electrical codes. Seals are especially recommended for installations that
use high-pressure or steam cleaning devices in proximity to the transmitter and/or sensor. The cementing material used on
the Millennium II sensors is suitable for an operating temperature range of
(-55 °C to + 85 °C).
Guidelines
It is recommended that explosion-proof drains and conduit breathers be used. In some applications, alternate changes in
temperature and barometric pressure can cause ‘breathing’ which allows moist air to enter and circulate inside the conduit.
Joints in the conduit system are seldom tight enough to prevent this ‘breathing’.
Threaded connections on the enclosure between the enclosure and conduit pipe need to be sealed with thread tape, such
as Teflon tape, or something similar.
Hydrophobic filters (IPF-001) may be used to protect sensors from water.
It is the responsibility of the installer to install conduit seals where necessary, and to design conduit runs to ensure that
condensation does not accumulate and collect inside the enclosure.
