2-4 Installation
MN1269
Signal Wiring
All signal wiring and limit circuit wiring need not be larger than 22 AWG gauge. Signal
circuits, including the tachometer, should employ twisted, shielded pairs. Proper
termination of shielded cables is important to avoid creating ground loops or otherwise
degrading the noise immunity of the servo package. Cable shields should be terminated
at one end only. The other end should be left floating but insulated by electrical tape or
some other means to prevent contact with any metallic part. In most applications,
satisfactory noise immunity will be realized with the signal line shields terminated at the
respective signal input points. Note: Always reference the shield to the low side of the
signal wires which the shield is to protect. Earthing or grounding the shield does little
good unless the signal is also referenced to the same point. It is important to maintain
the continuity of cable shields through any intervening connector and/or terminal blocks.
Try to minimize the length of unshielded cable at these points.
Electrical Noise Suppression
Electrical noise suppression requires a thorough system design using a combination of
good grounding practices, shielded cable, cable separation and suppressors. The
customer must provide suppression of transient voltages in his equipment, which may
occur when interrupting current to an inductive load.
Wiring Instructions
Power Wiring
Wire the unit according to the National Electrical Code (NEC) as well as your local
requirements. Motor power and AC input wiring should be appropriate for the continuous
rated current for the motor being used.
The connections and the wiring can vary between chassis depending on the user’s
requirements and the terminal strip options chosen.
Note: Refer to the drawing in Appendix A before connecting the unit and integrating
it into the system.
Note: LD-2 units have screw type terminals for L1 and L2.
LD-4 units have screw type terminals for L1, L2 and L3.
Figure 2-2 Power Wiring
Servo Systems Co. • 115 Main Road • P.O. Box 97 • Montville, NJ, 07045-0097
(973) 335-1007 • Toll Free: (800) 922-1103 • Fax: (973) 335-1661
www.servosystems.com
