GE Industrial Solutions DV-300 DC Drive Users Manual - Manual (Page 76)

GEI-100332Ga
——— WIRING PROCEDURES ———
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External devices
As for the installation of contactors, protection devices, chokes, filters and other external devices it is neces-
sary to follow the indication given in the previous chapters. The same theory is valid for motors, encoders and
tachometers.
Connection cables
The encoder shielded cable must be made of twisted pairs. The connection cables of the encoders and of the
motors, if possible, should be connected directly to the device, without going through support terminal strips.
The shieldings of the signal conductors have to be ground connected on both sides. Anyway, for all analog and
digital signals with very long connections (outside the electric board), it is suggested to have a ground connec-
tion only on the converter side, in order to avoid possible noises caused by the closing of the ground loops. In
particular cases it could be necessary to connect the shielding on both sides, thus granting the point equipoten-
tiality via suitable connection cables.
The encoder cable has to be made up of twisted loops with the global shielding connected to the ground on the
converter side. Avoid to connect the shielding on the motor side connector. In particular cases (cable longer than
100 meters, strong electromagnetic noise), it could be necessary to use a cable with a shielding on every loop to
be connected to the power supply ground. The global shielding has always to be ground connected.