Chapter 1 Safety 3
EV2100 Series Variable Speed Drive User Manual
1.3.1 About Motor and Load
Compared to the power frequency operation
The drive is a voltage type variable speed drive.
The output voltage is in PWM wave with some
harmonics. Therefore, temperature rise, noise and
vibration of motor are higher.
Low Speed Constant Torque Operation
Driving a common motor at low speed for a long
time, the drive’s life will be reduced due to the
deteriorating heat dissipation effect, so a special
variable frequency motor is needed if long time
operation with constant torque is required
.
Motor’s over-temperature protecting threshold
The drive can protect the motor from
over-temperature. If the ratings of the driven motor
are not in compliance with the drive, be sure to
adjust the protective threshold to ensure the motor
is properly protected.
Operation above 50Hz
If the motor operated above 50Hz, motor vibration,
noise as well as bearing and mechanical devices
sufficient should be taken into consideration.
Lubrication of mechanical devices
Over time, the lubricants in mechanical devices,
such as gear box, geared motor, etc. when running
at low speed, will deteriorate. Frequent
maintenance is recommended.
The mechanical resonance point of load
The drive system may encounter mechanical
resonance with the load when operating within
certain band of output frequency. Skip frequencies
have been set to avoid it.
Frequent startup/shutdown
The drive should be started and stopped via its
control terminals. It is prohibited to start and stop
the drive directly through input line contactors,
which may damage the drive with frequent
operations.
Insulation of Motors
Before using the drive, the insulation of the motors
must be checked, especially, if it is used for the first
time or if it has been stored for a long time. This is
to reduce the risk of the Drive from being damaged
by the poor insulation of the motor. Wiring diagram
is shown in Fig. 1-1. Please use 500V insulation
tester to measure the insulating resistance. It
should not be less than 5M
Ω
.
电动机
兆欧表
接地体
EV2000
EV2100
Mega-Ohm-Meter
Motor
Earthing conductor
EV2100
电动机
兆欧表
接地体
EV2000
EV2100
Mega-Ohm-Meter
Motor
Earthing conductor
EV2100
Fig. 1-1 Checking the insulation of motor
1.3.2 About Variable Speed Drive
Varistors or Capacitors Used to Improve the
Power Factor
Don't connect any varistor or capacitor to the
output terminals of the drive, because the drive's
output voltage waveform is pulse wave, otherwise
tripping or damaging of components may occur; in
addition, don't install circuit breaker or contactor at
the output side of the drive as shown in Fig.1-2.
M
U
V
W
EV2000
EV2100
Fig. 1-2 Capacitors are prohibited to be used.
Circuit breakers connected to the output of the
drive
If circuit breaker or contactor needs to be
connected between the drive and the motor, be
sure to operate these circuit breakers or contactor
when the drive has no output, to avoid damaging of
the drive.
