NATIONAL ALUMINIUM COMPANY LIMITED - Rites

Encl: IP-45
Control voltage – 220 V DC
BELT SWAY SWITCH
The belt sway switch shall be shall be auto reset type and provided at both ends and at an
interval of 50 mtrs (for conveyor length greater that 200 mtrs) on both sides of conveyors and
also before and after belt weighing system on both sides. It shall be of auto reset type.
The belt sway switch shall be industrial heavy duty type housed in dust and vermin proof box
with degree of protection IP IP-54. 54. The switch shall be designed that conveyor does not come in
direct contact with the switches and mechanism shall have strong rest spring to absorb high
impact of loaded belt edge.
The switch element shall be self rest type and shall have 2NO+2NC contacts each rated for
10A, 240V AC. It shall be suitable for ambient temp. of 600C. Resetting spring mechanism,
built in terminal box, actuating ctuating rollers, roller shafts, supporting frame, etc shall be provided as
per requirement. Belt sway switch shall be J&N make.
PULL CHORD SWITCH
Pull chord switches shall be auto reset type industrial heavy duty enclosed in dust and vermin
proof enclosure with degree of protection IP IP-65. 65. They shall be provided with following
facilities;
• Switch elements shall be 2NO+2NC each rated for 10A, 240V AC.
• Automatic locking arrangement in the operated position with manually reset
• Snap action type for posi positive operation of contacts
• Number of position shall be 11-0-1
• Separate compartment for built in terminal box
• Suitable base plate Pull rope shall be stranded galvanized steel wire with at least 1
mm thick PVC cover and having overall diameter of 6mm to 7m 7mm. m.
Pull rope switch shall be placed at an interval of 25 mtr on both sides of conveyor with
minimum of one pair for conveyor length less than 25 mtr.
ZERO SPEED SWITCH
The unit shall be provided with MS flags, sensing probes, monitoring unit and inte interconnecting
special cables. The unit shall be of multi speed range with setting facility and shall be provided
with output contacts (2NO+2NC) with facility for initial bypass adjustable time delay, nuisance
tripping delay and analog/digital speed display. 4-20mA 20mA isolated DC signal shall be applicable
for external metering. Sensing probe shall be provided with metallic enclosure of degree of
protection IP-67 67 and LED lamp for visual indication of correct functioning of sensing probe.
Technical Specification:Sec-6, Electrical
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