The immunity of 1336 PLUS drives to externally generated interference is good. Usually, no special precautions are required beyond the installation practices provided in this publication.
It is recommended that the coils of DC energized contactors associated with drives be suppressed with a diode or similar device, since they can generate severe electrical transients.
Careful attention must be given to the arrangement of power and ground connections to the drive to avoid interference with nearby sensitive equipment. The cable to the motor carries switched voltages and should be routed well away from sensitive equipment. The ground conductor of the motor cable should be connected to the drive ground (PE) terminal directly. Connecting this ground conductor to a cabinet ground point or ground bus bar may cause high frequency current to circulate in the ground system of the enclosure. The motor end of this ground conductor must be solidly connected to the motor case ground.
Shielded or armored cable may be used to guard against radiated emissions from the motor cable. The shield or armor should be connected to the drive ground (PE) terminal and the motor ground as outlined above.
Common mode chokes at the drive output can help reduce common mode noise on installations that do not use shielded cable. Common mode chokes can also be used on analog or communication cables. Refer to page 2–34 for further information.