Danfoss ADAP-KOOL AKD 102 Operating Instructions Manual page 35

Electrical Installation
5.1.10 How to Connect Motor - Introduction
See section General Specifications for correct dimensioning of motor cable cross-section and length.
•
Use a screened/armoured motor cable to comply with EMC emission specifications (or install the cable in metal
conduit).
•
Keep the motor cable as short as possible to reduce the noise level and leakage currents.
•
Connect the motor cable screen/armour to both the decoupling plate of the frequency converter and to the metal
of the motor. (Same applies to both ends of metal conduit if used instead of screen.)
•
Make the screen connections with the largest possible surface area (cable clamp or by using an EMC cable gland).
This is done by using the supplied installation devices in the frequency converter.
•
Avoid terminating the screen by twisting the ends (pigtails), as this will spoil high frequency screening effects.
•
If it is necessary to break the continuity of the screen to install a motor isolator or motor relay, the continuity must
be maintained with the lowest possible HF impedance.
Cable length and cross-section
The frequency converter has been tested with a given length of cable and a given cross-section of that cable. If the cross-
section is increased, the cable capacitance - and thus the leakage current - may increase, and the cable length must be
reduced correspondingly.
Switching frequency
When frequency converters are used together with sine wave filters to reduce the acoustic noise from a motor, the
switching frequency must be set according to the sine wave filter instruction in 14-01 Switching Frequency.
Precautions while using Aluminium conductors
Aluminium conductors are not recommended for cable cross sections below 35 mm2. Terminals can accept aluminium
conductors but the conductor surface has to be clean and the oxidation must be removed and sealed by neutral acid free
Vaseline grease before the conductor is connected.
Furthermore, the terminal screw must be retightened after two days due to the softness of the aluminium. It is crucial to
ensure the connection makes a gas tight joint, otherwise the aluminium surface will oxidize again.
All types of three-phase asynchronous standard motors can
be connected to the frequency converter. Normally, small
motors are star-connected (230/400 V, D/Y). Large motors
are delta-connected (400/690 V, D/Y). Refer to the motor
name plate for correct connection mode and voltage.
NOTE
In motors without phase insulation paper or other insulation reinforcement suitable for operation with voltage supply (such
as a frequency converter), fit a sine-wave filter on the output of the frequency converter. (Motors that comply with IEC
60034-17 do not require a Sine-wave filter).
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ADAP-KOOL Drive Operating Instructions
Illustration 5.11 Terminals for motor connection
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MG.11.L4.02 - ADAP-KOOL Drive
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