| Speed
Increasing Drives -Multiply SF by SR Factor |
TYPES OF PRIME MOVE |
SR Factor
Speed Ratio. 1.00 to 1.24 -Nil
Speed Ratio. 1.25 to 1.74 -1.05 Speed Ratio. 1.75 to 2.49 - 1.11
Speed Ratio. 2.50 to 3.49 -1.18
Speed Ratio. 3.50 to over -1 .25 |
Soft Start
Electric Motor
AC-StarDelta Start
DC-Shuntwould
I.C. Enignes with 4 or more cylinders
All prime movers fitted with soft starters.
centrifugal clutch.
Fluid powder coupling. |
Heavy Start
Electric Motor
AC-Direct on line start
DC-Series & compound wound
I.C. Engines with less than 4 cylinders. |
| Types of Driven
Machines |
Hours per
Day Duty
Upto 10 Over 10 to 16 Over 16 |
Hours per Day Duty
Upto 10 Over 10 to 16 Over 16 |
LIGHT DUTY
Conveyors (uniform load) Exhaust Fans
(max 7.5 kw)
Blowers, Pumps, Compressors
(Centrifugal) Generators.
Shifters (Light), Agitators (Liquid) |
1.0 |
1.1 |
1.2 |
1.2 |
1.2 |
1.3 |
MEDIUM DUTY
Agitators
& Mixers, Compressors ( with 3, or more cylinders) Rotary pumps, Conveyors
(non-uniform load).
Washing
Machine, Line Shafts, Printing Machines &
Screens. |
1.1 |
1.2 |
1.3 |
1.3 |
1.3 |
1.4 |
HEAVY DUTY
Pumps, Compressor,
(Reciprocating)
Bucket Elevator, Rotary Pumps,
Conveyors, Hammer Mills, Rubber Mixers. Pulverisers, Vibrating Screens, Textile Machinery. |
1.2 |
1.3 |
1.4 |
1.4 |
1.5 |
1.6 |
EXTRA
HEAVY DUTY
Crushers (Gyratory, Jaw, Roll)
Mills
(Ball, Rod, Tube). |
1.3 |
1.4 |
1.5 |
1.5 |
1.7 |
1.8 |
