HNC Electric HV480 Series, Руководство пользователя

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3) Main loop terminal of frequency inverter of 45kw and above:
Description of main circuit terminal of three-phase frequency inverter
Terminal
marking
Name Description
R,S,T
Three-phase power supply input
terminal
Connection point for AC input three-phase power supply
㊀
,
㊉
Negative and positive terminals of
DC bus
Common DC bus input point
㊉ ,PB Brake resistor connection terminal Brake resistance connection point
㊉ ,P+ DC reactor connection terminal
U,V,W frequency inverter output terminal Connecting three-phase motor
Earth terminal Earth terminal
2.2.2 Main circuit wiring method and wiring matters needing attention:

Input power supply R, S, T: input side wiring of frequency inverter, no phase sequence requirements.

Terminals
⊕
and Θ DC bus: please note that there is still a high residual voltage in the DC bus just after the
power failure, so it must wait at least 15 minutes later, or confirm that the voltage is less than 36 V before
touching, otherwise there is danger of electric shock.

When selecting an external brake unit, pay attention to the positive and negative polarity, which cannot be
reversed, otherwise, the frequency inverter will be damaged or even damaged by fire. In order to prevent stray
inductance from affecting the braking effect, the wiring length of the braking unit should not exceed 5m.
Twisted pair or tight double wire should be used for parallel preparation, and non-inductive resistance should
also be used for braking resistance.

Brake resistance connection terminals
⊕
, PB
：
22kW G type machines and the following specifications are
models with built-in brake function. The wiring precautions for the brake resistance are the same as those for the
output side U, V, and W: the frequency inverter capacitors or surge absorbers cannot be connected to the output
side of the frequency inverter, otherwise, the frequency inverter will often be protected or even damaged. When
the motor cable is too long, due to the influence of the distributed capacitance, it is easy to generate electrical
resonance, thus causing the motor insulation to be damaged or causing a large leakage current to cause over
current protection of the frequency inverter. When the length of the motor cable is greater than 100 m, an AC
output reactor must be installed.

Earthling terminal : the terminal must be reliably grounded, and the resistance value of grounding wire must
be less than 0.1Ω. Failure to do so will result in work of equipment is abnormal or even damaged Do not share
the earthling terminal with the N terminal of the zero line of the power supply.

See [2.2.4 inverter standard wiring diagram] for wiring method].

Frequency inverter on/off operation should avoid frequent power-up and power-down operations (less than twice
per minute) or direct start-up operations of the frequency inverter through contactors. Refer to the following table
for air switch, contactor and conductor section.