Hanbell RC2-AVI Series, Manual

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5. Electrical data and design
5.1 Motor design
HANBELL RC2-AVI series screw compressors are equipped with Y-
Δ motor for soft start with a frequency inverter,
VFD. The motor winding is especially designed and its insulation is enhanced for a wide spectrum of rotation frequency.
During start, before reaching the specified operating condition, the current is increased proportionally with time to the
rated amp. Because the motor voltage is low during start, the starting current and starting torque is also low.
5.2 Electrical installation with VFD
The general connection diagram of inverter is shown in Figure 5.1. An AC reactor should be installed between the
power supply and the inverter in order to prevent power system from serious breakdown.
Figure 5.1: RC2-AVI compressor & VFD installation diagram
5.3 V-F diagram
The motor of RC2-AVI series compressor is designed for variable speed control. Its voltage vs. frequency characteristic
diagram is as shown in Figure 5.2. When setting the inverter by its operation manual, please choose the same V/F
characteristic as shown in Figure 5.2 in order to operate the compressor with proper settings.
Figure 5.2: RC2-AVI motor V/F diagram
Variable Frequency Drive (VFD)
Motor
Inverter
Control Circuit
Control Voltage
In
p
u
t
V
o
lt
a
g
e
3
Φ，
2P
，Δ
AC Reactor
(Optional)
AC Reactor