Emheater EM12 Series, User Manual

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EM12 User’s Manual 3. Installation of Frequency Inverter
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frequency setting.
Length of cable between the inverter and motor Carrier frequency (d6-00)
Less than 50m Less than 15kHz
Less than 100 m Less than 10kHz
More than 100m Less than 5kHz
3.9.3 Grounding Wiring

The inverter will produce leakage current. The higher the carrier frequency is, the larger the leakage current
will be. The leakage current of the inverter system is more than 3.5mA, and the specific value of the leakage
current is determined by the use conditions. To ensure the safety, the inverter and the motor must be grounded.

The grounding resistance shall be less than 10ohm. For the grounding wire diameter requirement, refer to 2.6
electrotype of main circuit peripheral devices.

Do not share grounding wire with the welding machine and other power equipment.

In the applications with more than 2 inverters, keep the grounding wire from forming a loop.
Diagram 3-7 Grounding Wire Connection Sketch Map
3.9.4 Countermeasures for Conduction and Radiation Interference
Diagram 3-8 Connection of conduction and radiation interference solutions

When the input noise filter is installed, the wire connecting the filter to the inverter input power end shall be as
short as possible.

The filter enclosure and mounting cabinet shall be reliably grounded in large area to reduce the back flow
impedance of the noise current Ig.

The wire connecting the inverter and the motor shall be as short as possible. The motor cable adopts 4-core
cable, with the grounding end grounded at the inverter side, the other end connected to the motor enclosure.
The motor cable shall be sleeved into the metal tube.

The input power wire and output motor wire shall be kept away from each other as far as possible.

The equipment and signal cables vulnerable to influence shall be kept far away from the inverter.

Key signal cables shall adopt shielding cable. It is suggested that the shielding layer shall be grounded with
360-degree grounding method and sleeved into the metal tube. The signal cable shall be kept far away from the
inverter input wire and output motor wire. If the signal cable must cross the input wire and output motor wire,
they shall be kept orthogonal.

When analog voltage and current signals are adopted for remote frequency setting, twinning shielding cable