Baldor VS1GV21-1B, Installation & Operating Manual, Page: 27 / 204

Power Wiring 4-11 MN765
4.10 M-Contactor
If required by local codes or for safety reasons, an M-Contactor (motor circuit contactor) may be installed. However,
incorrect installation or failure of the M-Contactor or wiring may damage the control. M-Contactor connections are shown
in Figure 4-9.
CAUTION: If an M-Contactor is installed, the control must be disabled for at least 200msec before the
M-Contactor is opened. If the M-Contactor is opened while the control is supplying voltage and
current to the motor, the control may be damaged. Before the control is enabled, the M-Contactor
must be closed for at least 200msec.
Figure 4-9 Motor Connections and Optional Connections
*Optional components not provided with control.
Baldor
Control
* AC Motor
Note 1
*Optional
Load
Reactor
Note 1
A1 B1 C1
A2 B2 C2
T1 T2 T3
T1
T2 T3
G
Note 3
* Optional
RC Device
Electrocube
RG1781-3
8
9
*
M Enable
J2
* M-Contactor
To Power Source
(Rated Coil Voltage)
*M=Aux Contacts of optional M-Contactor
GND
*Optional M Contactor Connections
Note 2
See recommended tightening torques in Table A-2.
M
M
NOTES:
1. Metal conduit should be used. Connect conduits so the use of the Load Reactor or RC Device does not interrupt EMI/RFI
shielding.
2. See Line/Load Reactors described previously in this section.
3. Use same gauge wire for ground as for T1, T2 and T3 for AA, B, and C controls. For size D, E and F controls, size the
grounding conductor per the local electrical code.
4.11 Long Motor Leads
The wire leads that connect the motor to the control are critical in terms of sizing, shielding and the cable characteristics.
Short cable runs are usually trouble free but fault-monitoring circuitry can produce numerous faults when long cables (over
100 feet) are used.
• 100+ft (30m): Baldor recommends adding an optional load reactor to the output of the control.
• 250+ft (75m): Baldor recommends adding and optional load reactor and common mode choke to the control.
The load reactor and/or common mode choke should be placed in close physical proximity to the control. Unexpected
faults may occur due to excessive charging current required for motor cable capacitance. If you use long motor leads and
experience unexpected trips due to overload conditions and are not sure how to correctly size and connect the optional
load reactors, please contact your Baldor representative.