Inovance MD520 Series, Hardware Manual

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System Structure
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20
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Table 3–1 Usage description of peripheral electrical devices
Device
Description
Circuit breaker
It is installed between the power supply and the AC drive input
side.
●
Circuit breaker for protection against short circuit: It cuts
off the power supply when overcurrent occurs on
downstream devices.
●
Earth leakage circuit breaker: It provides protection against
potential leakage current during AC drive running to
prevent electric shock and even a fire. Select proper earth
leakage circuit breakers as needed.
Fuse
It protects downstream semiconductor components in case of
short circuit.
Electromagnetic
contactor
It is used to switch on or off the AC drive. Do not use the
contactor to power on or off the AC drive frequently (time
interval ≥ one hour) or use the contactor to directly start the AC
drive.
AC input reactor
It provides the following functions:
●
Improves the input‑side power factor.
●
Eliminates high‑order harmonics at the input side
effectively and prevents other devices from being damaged
caused by distortion of voltage waveform.
●
Eliminates input current unbalance caused by unbalance
between the power supply phases.
EMC filter
It provides the following functions:
●
Reduces external conduction and radiation interference of
the AC drive.
●
Reduces conduction interference from the power supply to
the AC drive, thereby improving the anti‑interference
capacity of the AC drive.
Simple filter
It reduces external conduction and radiation interference of the
AC drive.
Braking resistor
For AC drive models containing letter B, the braking resistor is
optional. It dissipates regenerative energy during motor
deceleration.
Braking unit
For AC drive models not containing letter B, use a braking unit
(MDBUN) or recommended braking resistor of Inovance. The
braking unit dissipates regenerative energy during motor
deceleration.
Active front end (AFE)
unit
An AFE is an optional unit used to feed the energy generated by
the motor during braking back to the mains. With the AFE
installed, the braking unit and braking resistor are not required,
which reduces heat emission. Inovance AFE features energy
efficiency, low noise, low harmonic, and high power factor.