Operation - Michell Instruments PROMET EExd Installation, Operation & Maintenance Manual

PROMET EExd Process Moisture Analyzer Sampling Systems
____________________________________________________________
3.

OPERATION

Operation of the PROMET EExd Sampling Systems should be carried out in conjunction
with and referring to the PROMET EExd Process Moisture Analyzer Users Guide prior to
commencing system start-up procedure.
Before commencing the start up procedure it is essential to ensure the installation
conforms to the correct Hazardous area and local plant standards.
Check all cables are according to certificated approved specifications and as a minimum
are as described below:
Power Cable
Communications
Cable
Communications
Cable
There is a mandatory purge procedure stipulated as part of the hazardous area
certification of the PROMET EExd product. This procedure must be fully carried out prior
to any power or signal connections to the PROMET EExd being energised.
This procedure must also be carried out at any time following service or maintenance
periods that causes any of the PROMET EExd or associated gas handling equipment
sample lines to be disconnected.
It is not necessary to carry out this procedure if, during a shut down period, the sample
lines have not been disconnected, or if the power or signal connections only have been
disconnected.
Before commencement of the start-up procedure ensure that all power and signal
connections to the PROMET EExd flameproof enclosure are fully isolated and if
necessary observe the stipulated de-energisation period of 45 minutes.
Before any gas pressure is applied, check all gas inlet & outlet connections are fully
tightened up and that all valves and regulators are in the closed position.
BEFORE power is applied to the sampling system check that the PROMET EExd Power
Isolator switch is set to the OFF position.
Apply power to the sampling system and allow the temperature within the enclosure to
stabilise. This will prevent the possibility of condensation occurring within the gas
handling components during start-up.
____________________________________________________________
Minimum Cable Requirements
3 core, 0.75 mm² conductor area (6A)
Communications: For use with 4-20mA only or Modbus
only - 2 pairs, 0.5 mm² conductors and with an overall
braided screen.
For use with 4-20mA and Modbus - 4 pairs individually
screened, 0.5 mm² conductors and with a overall braided
screen.
www.michell.com
Installation, Operation & Maintenance Manual and User Guide
14