Baldor UM Series, Инструкция по установке и эксплуатации

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3-2 Receiving & Installation MN1213
Figure 3-1 Installing the Circuit Boards
Electrical Installation
All interconnection wires between the control, AC power source, motor, host
control and any operator interface stations should be in metal conduits. Use listed
closed loop connectors that are of appropriate size for wire gauge being used.
Connectors are to be installed using crimp tool specified by the manufacturer of
the connector. Only class 1 wiring should be used.
All wiring must performed to the requirements of the National Electrical Code
(NEC) and local requirements.
Electrical Noise Considerations
All electronic devices are vulnerable to significant electronic interference signals
(commonly called “Electrical Noise”). At the lowest level, noise can cause
intermittent operating errors or faults. From a circuit standpoint, 5 or 10 millivolts
of noise may cause detrimental operation. For example, analog speed and torque
inputs are often scaled at 5 to 10VDC maximum with a typical resolution of one
part in 1,000. Thus, noise of only 5 mV represents a substantial error.
At the extreme level, significant noise can cause damage to the drive. Therefore,
it is advisable to prevent noise generation and to follow wiring practices that
prevent noise generated by other devices from reaching sensitive circuits. In a
control, such circuits include inputs for speed, torque, control logic, and speed and
position feedback, plus outputs to some indicators and computers.
Relay and Contactor Coils
Among the most common sources of noise are the coils of contactors and relays.
When these highly inductive coil circuits are opened, transient conditions often
generate spikes of several hundred volts in the control circuit. These spikes can
induce several volts of noise in an adjacent wire that runs parallel to a
control-circuit wire. Figure 3-2 illustrates noise suppression for AC and DC relay
coils.