LOCAL PUSH BUTTON STATION TECHNICAL SPECIFICATION
This specification covers design, manufacture, testing and supply of Industrial Control stations.
All materials, equipment and accessories shall conform to latest edition of relevant Indian standards, some of which are listed below:
IS 2147: Degree of Protection provided by enclosures for low voltage switchgear
and Control gear.
IS 6875: Push buttons and related control switches.
IS 694: PVC insulated cables (for voltages up to 1100 volts) with copper
(PART I) conductors.
IS 4794: Push button switches.
IS 1248: Direct acting indicating analogue electrical measuring instruments
and their accessories.
IS 1336: Recommendations for the colour of push buttons.
Local control station shall be cast iron / cast aluminum enclosure as specified in the datasheet with IP55 protection. For outdoor use enclosure of local control station shall
Be weatherproof & shall be provided with canopy.
Enclosure door shall be bolted type with no component mounted on it except the push
button / selector switch operating knobs. Contact elements shall be mounted inside/ on
the base of control station. Suitable cutout with cemented clear glass shall be provided
on the door for Ammeter.
Padlocking facility for the stop pushbutton to be provided on the front plate if specified.
Suitable for connection of 2.5 mm² aluminum / copper conductors. Terminal design
must ensure secure & vibration – proof connections. Terminals for each push button to
be brought out separately into terminal chamber.
Enclosure of local control station shall be provided with external fixing lugs.
Enclosure of local control station shall be provided with two nos. external earth terminals each complete with 2 plain and one spring washers, and a nut.
Enclosure of all local control stations shall be provided with two cable entries ¾” E.T. at bottom unless specified otherwise. One entry to be blocked with rubber grommet.
Push buttons and other components required for local control station shall be as per data sheet.
Push buttons element shall have 1 NO & 1 NC momentary (unless specified otherwise in data sheet) type contacts of rating 5A, 500 V AC. The knobs of start and stop push buttons shall be green and red in colour respectively. All stop push buttons shall have stay put feature and mushroom knobs.
Ammeters shall be CT operated (CT provided elsewhere) with 1 Amp. CT secondary rating. All ammeters shall be Industrial grade ‘A’ accuracy and shall have a basic range of 0-1/6 with suppressed scale for 1-6. Calibration will be as per data sheets. Ammeters shall conform to IS 1248.
Indicating lamps shall be low burden filament type / neon / LED with bayonet cap. Lamp cover shall be glass or other equivalent unbreakable material.
Selector switches shall be cam type, spring loaded with rating and other details as per purchase data sheet.
Local control stations shall be completely wired up to terminals with 2.5 sq.mm. Copper conductor PVC insulated cables. Wiring shall be carried out as per Contractor’s wiring diagrams, where furnished. A terminal block to be provided for connection of external cables.
Terminals to be clamp type and suitable for 2.5 sq. mm. conductor. Ample space to be provided between gland plate and terminals.
All metal surfaces shall be thoroughly cleaned and degreased to remove scale, rust, grease and dirt. Fabricated structures shall be pickled and then rinsed to remove any trace of acid. The surface shall be prepared by applying a coat of phosphate paint and coat of yellow zinc chromate primer. The surface shall be made free from all imperfections before undertaking the finishing coat.
After preparation of the surface, it shall be powder coated with two coats of epoxy based final paint. Colour shade of final paint shall be as specified in datasheet. The finished panels shall be dried in stoving ovens in dust free atmosphere. Panel finish shall be free from imperfections like pinholes, orange peels, runoff paint etc.
All unpainted steel parts shall be cadmium plated or suitably treated to prevent rust formation. If these parts are moving elements then they shall be greased.
Each control stations to be provided with rear engraved Perspex nameplates with white
Letters on black background. (Inscription details will be furnished separately).
Push buttons switches, indicating lamps etc. to be provided with legend plates giving their respective function.
DRAWING & INFORMATION
Drawings and Test Certificates as stipulated in Vendor Document Requirements shall be furnished.
General Arrangement drawing showing all dimensions, cable entry details, earthing terminals, mounting arrangement etc. shall be furnished for Owner / consultant’s approval before manufacturing is started.
TESTING & INSPECTION
Vendor to make all arrangement to carryout the following tests:-
a) Physical Inspection.
b) Operation test.
c) Insulation test.
d) H.V. test.
Purchaser reserves the right to inspect the control stations and witness the tests at manufacturer’s works.
The bidder shall provide with his quotation, separate priced list of recommended operation and maintenance spares.
Quality assurance shall follow the requirement of the “VAISHNO CFG” QA document applicable to local control stations concerned.
QA involvement will commence at bid stage and follow through to completion and acceptance, thus ensuring total conformity to Purchaser’s requirement.
Deviations from specifications must be stated in writing at the time of the bid stage. In the absence of such a statement it will be assumed that the requirements of the specification are met without exception.
VAISHNO SWITCHGEAR PVT. LTD.