NATIONAL ALUMINIUM COMPANY LIMITED - Rites

All instruments and control devices provided on panels shall be of miniaturized design,
suitable for modular flush mounting on panels with front draw out facility and flexible plugin
connection at rear.
All electronic modules shall have gold plated connector fingers and further all input and
output modules shall be short circuit proof. These shall also be tropicalised & components
shall be of industrial grade or bette better.
4.26 ELECTRICAL NOISE CONTROL
The equipment furnished by the Contractor shall incorporate necessary techniques to
eliminate measurement and control problems caused by electrical noise. Areas in
Contractor's equipment which are vulnerable to electrica electrical l noise shall be hardened to
eliminate possible problems. Any additional equipment, services required for effectively
eliminating the noise problems shall be included in the proposal. The equipment shall be
protected against ESD as per IEC IEC-801- 2. Radio Frequency equency interference (RFI) and Electro
Magnetic Interference (EMI) protection against hardware damage and control system mal-
operations/errors shall be provided for all systems.
4.27 TAPPING POINTS FOR MEASUREMENTS
Tapping points shall include probes, wwherever
herever applicable, for analytical measurements and
sampling. For direct temperature measurement of all working media, one stub with internal
threading of approved pattern shall be provided along with suitable plug and washer. The
Contractor will be intima intimated ted about thread standard to be adopted. The following shall be
provided on equipment by the Contractor. The standard which is to be adopted will be
intimated to the Contractor. Temperature test pockets with stub and thermo well Pressure
test pockets
4.28 ELECTRONIC MODULE/COMPONENT DETAILS
The Contractor shall have to furnish all technical details including circuit diagrams,
specifications of components, etc., in respect of each and every electronic card/module as
employed on the various solid state as well as microprocessor based systems and equipment
including conventional instruments, peripherals etc. It is mandatory for the Contractor to
identify clearly the custom built ICs used in the package. The Contractor shall also furnish the
details of any equivalents uivalents of the same.
4.29 JUNCTION BOXES
The junction boxes shall be made of minimum 2 mm thick sheet steel. Gland plates shall be
removable type and made of 3 mm thick sheet steel. The boxes shall be provided with
detachable cover or hinged door with captive screws. Top of the box shall be arran arranged to
slope towards the rear of the box. The box shall be hot dip galvanized and shall be provided
with suitable neoprene gaskets to achieve degree of protection of IP IP--55
as per IS: 2147.
Adequate spacing shall be provided to terminate the external cables cables. . The boxes shall be
suitable for mounting on various types of steel structures. The terminal blocks provided shall
be of 650 V grade, rated for 10 A for control cables. Suitable numbering for terminal blocks
Technical Specifications: Sec-5,General Techn chnical Requirements
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