| Motor
winding |
~
Speed tolerance |
Typical
rated speeds at 60Hz |
Start/Stop
frequency |
Coast
without brake |
Coast
with dynamic braking |
Starting
torque (% of rated torque) |
Pros |
Cons
|
| Split Phase
(SI) |
+/-3% |
1700-1750
(4-pole)
3450
(2-pole) |
Up to 6
per hour |
20 to 600
revolutions |
0.5 to
6 revolutions |
175%
and up |
No capacitors
|
Switch
life 50k to 250k starts |
Permanent
Split Capacitor
(CI) |
+/-3% |
1700-1750
(4-pole)
3450
(2-pole) |
Up to 10
per minute |
20 to 600
revolutions |
0.5 to
6 revolutions |
90 to
100% |
Very reliable,
Low starting current |
Low
starting
torque |
| Three Phase
(PP, Non-synchronous) |
+/-3% |
1700-1750
(4-pole)
3450
(2-pole) |
Up to 10
per minute |
20 to 600
revolutions |
0.5 to
6 revolutions |
200 to
400% |
Most reliable
and efficient, No cap/switch |
Requires
three-phase power supply |
| Reluctance
Synchronous Split Phase (SY) |
near 0% |
1800
(4-pole)
3600
(2-pole) |
Up to 6
per hour |
20 to 600
revolutions |
0.5 to
6 revolutions |
110 to
150% |
Same as
split-phase, plus exact speed |
Switch
life 50k to 250k starts |
| Reluctance
Synchronous Capacitor (YC) |
near 0%
|
1800
(4-pole)
3600
(2-pole) |
Up to 10
per minute |
20 to 600
revolutions |
0.5 to
6 revolutions |
80 to
100% |
Exact speed,
Very reliable, Low starting current |
Low starting
torque |
| Reluctance
Synchronous Three Phase (YP) |
near 0% |
1800
(4-pole)
3600
(2-pole) |
Up to 10
per minute |
20 to 600
revolutions |
0.5 to
6 revolutions |
200 to
500% |
Exact speed,
Most reliable and efficient, No cap/switch |
Requires
three-phase power supply |
| Brushless
DC (BLDC) |
near 0%
|
2500 |
Up to 10
per minute |
20 to 600
revolutions |
0.5 to
6 revolutions |
175%
and up |
Exact speed
control |
Requires
a control board |
