Elcon HiD 2000 Series, User Instruction Manual

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6-1
6 Servicing
6.1 Maintenance
Introduction
Elcon Instruments HiD range isolator modules do not require any particular maintenance under normal operating
conditions. They are designed to operate trouble free and with high stability for long time. Periodic checks (yearly
based) can be scheduled to verify their performances, based on the following:
•
remove dust from module and termination boards. Dust on circuit board facilitate corrosion in humid
environments producing effects similar to that of a corrosive atmosphere, and reduces the thermal
exchange rate.
•
all wiring to the Hazardous Area and Safe Area side are properly made and screws are securely tight.
•
modules are of the exact model specified and properly plugged into the correct position on the
Termination Board.
•
cables are not damaged, of the correct type and properly routed in the trunks.
•
cubicle or enclosure where the instruments are installed are not damaged and provide the adequate
protection level and ventilation
All faulty unit (module or backplane) should be returned to Elcon factory or Reps. for repairs or replacement.
WARNING:
ANY REPAIR MADE BY UNAUTHORIZED OR NOT SKILLED PERSONNEL MAY COMPLETELY INVALIDATE
THE INTRINSIC SAFETY OF THE INSTRUMENTS. REPAIR NOT MADE BY ELCON INSTRUMENTS IS FULLY
AT USER'S RISK AND RESPONSIBILITY AND THE WARRANTY TERMS OF THE MODULE WILL BE NULL
AND VOID TO ALL EFFECT
6.2 Functional Check & Troubleshooting
General Information
BE CAREFUL TO PERFORM ANY MEASUREMENT WITH CERTIFIED TESTING EQUIPMENT WHEN
OPERATING IN HAZARDOUS AREA ENVIRONMENT.
The personnel performing installations and maintenance should refer to the specific documentation and Codes of
Practice for Intrinsic Safety.
They should be qualified with the technical background that in some countries is a requisite to obtain the license
for repairing certified equipment.
Before going deeper into isolator troubleshooting, check for the following:
•
check the 24 Vdc supply is within the specified limits (20.4 Vdc to 30 Vdc), and correct polarity applied.
•
check that on the Board the “Power ON” green LED in ON; if not, check the supply fuse, replace it if it
is blown; ratings are 2A for the 8 positions Board, 4A for the 16 positions Board.
•
check that the “PWR On” green LED on the isolators are ON (Bus powered type).
•
check that the Fault red LED on the Board and on the isolators are not lit
•
check wiring connection, polarity, cable routing and separation from non I.S. conductors.
•
check correct module type has been plugged.
•
check output signals to match the application
•
replace the eventually faulty modules with spare healthy unit by simply lifting the side yellow tabs of the
module case and unplugging it from the backplane, without disturbing any of the wiring.
With this concept there are no live wires or loose plugs left hanging from the cable truncking during the
plant commissioning, repairing or maintenance phases, which may cause an additional hazard.
In the following, step by step instructions are provided to check the isolators functional behaviour. This is both
useful as a troubleshooting aid and to enable a straightforward verification of key units specifications. Current
consumption, power dissipation and a few other non critical parameters are not covered by the procedure (but can
anyway be easily tested by the user). The focus is on accuracy and other application-critical specifications.
When some doubt exist about a faulty unit, please follow the check procedure suggested in this section. When the
problem is confirmed, the unit should be returned for repair to the nearest authorised representative of Elcon
Instruments, clearly specifying which of the procedure verification steps were not passed.
To carry on the functional check, the following instrumentation is required:
- a stabilised
power supply , 0-30 V range, current > 200 mA; the power supply should guarantee an error lower
than 0.1 V (with respect to the specified voltage) measured at the isolator terminals;