LT-S-(L) Technical manual
compressor. When this occurs, we recommend to use an adjustable Y-Δ timer or time
delayer to lengthen the time for MCM, MCS conversion — it takes 0.25 to 0.5
seconds to re-energize. Please refer to Y-Δ shift time graph for details. Because motor
is not powered during Y-Δ shift, shorter Y-Δ shift span is suggested to prevent second
start due to decreased rotation speed. However, if Y-Δ shift span is too short, above
mentioned pseudo short circuit might occur.
Figure 6-2. Y-
△
Shift Time
Y-Δ start features
1
）
Starting current in Y connection is 1/3 of lock rotor ampere.
2
）
Starting torque in Y connection is 1/3 of lock rotor torque.
3
）
Acceleration of motor rotor becomes smaller at full-load starting, therefore
compressors require starting at partial load.
Except for Y-Δ start, concerning soft start or reactance start, please kindly contact
Hanbell for further information.
6.1.2
Power requirements
Power limitation
Voltage limitation
Long term operation: within ±5% of rated voltage
Instant operation: within ±10% of rated voltage
Frequency: within ±2%of rated frequency
Caution
In the region where the electricity power is unstable, install an additional
