- 2070 Chaitra
Individual, group and multi-motor drives
Short answer
Group drive: one motor runs multiple machines via line shaft; low cost, low efficiency, no individual control. Individual drive: each machine has its own motor; high efficiency, flexibility, fault isolation. Multi-motor drive: multiple motors on one machine, each for a mechanism; best control and automation, higher cost; used in cranes, rolling mills.
Compare individual group and multi-motor drive system.
Electric drives are classified by how motors are arranged with respect to machines.
- Group drive: one motor drives several machines through a line shaft, belts and pulleys.
- Individual drive: each machine has its own motor (one motor may drive all mechanisms of that machine through gears).
- Multi-motor drive: one machine has several motors, each driving a separate mechanism (e.g. an overhead crane with hoist, trolley and bridge-travel motors).
Group Individual Multi-motor
M=shaft= M1-[m/c1] +--- machine ---+
| | | M2-[m/c2] | M1 M2 M3 |
m1 m2 m3 M3-[m/c3] | hoist trolley |
| travel |
+---------------+
| Point | Group | Individual | Multi-motor |
|---|---|---|---|
| Motors per machine | Fraction of one | One | Several |
| Initial cost | Lowest | Medium | Highest |
| Efficiency | Low (transmission losses, underloaded motor) | High | Highest |
| Speed control | Not individually | Per machine | Per mechanism |
| Reliability | Motor fault stops all | Fault stops one machine | Fault stops one mechanism |
| Layout flexibility | Poor (line shaft) | Good | Very good |
| Safety, cleanliness | Belts unsafe, noisy | Good | Good |
| Control complexity | Simple | Simple | Complex (coordination) |
| Automation | Difficult | Possible | Best suited |
| Applications | Old workshops, small flour mills | Lathes, drilling machines, pumps | Cranes, rolling mills, paper and textile machines, machine tools |
Group drive is cheap but wasteful and inflexible. Individual drive is the normal choice in modern industry. Multi-motor drive gives the best performance and automatic control for complex machines, at higher cost.
✓ Answer checked by Claude Opus 5.5 (high effort)
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