Basic Installation and Operation Guide VMX Series Digital Solid State Soft Starters 18 – 1000A
Page 10 of 27
Figure 3:
VMX Power Connections
Integral
Bypass
Contactor*
VMX Starter
.
Disconnect
or
Circuit
Breaker
Solid State
.
Over Load
.
MTR
G
R /
L1
T /
L3
S /
L2
U /
T1
W /
T3
V /
T2
Electrical connections
Power Terminations
All line and load power terminations are to be made to plated copper Bus Tabs located on each unit. Bus tabs
are pre-drilled to accept industry standard bolts.
The following power schematic provides the termination points as they are labeled on the unit. This is
diagrammatic only. All power terminations are physically located on the bottom of each unit. Refer to local code
standards for wire sizing and length.
Connect appropriately sized power conductors to the unit input terminals marked L1, L2, L3 (R, S, T for IEC
users). Avoid routing power wires over the control board or display. Note: If control power is present, but line
power is disconnected from L1, L2, L3, the display will show
[n3PH]
indicating “no 3 Phase”.
Connect the motor leads to the unit load terminals marked T1, T2, T3
(U, V, W for IEC users). Soft Starters such as the
VMX Series
cannot
operate without a load, even for testing. The
VMX Series
will trip on
“Phase Loss” if any or all of the conductors are disconnected from the
load terminals. Contact the Factory for assistance in no-load testing.
Caution!
Never interchange input and output connections to the
unit. This could cause excessive voltage in the control
logic circuit and may damage the unit.
Bypass Contactor
*
Bypass Contactors are integral (built-in) on all VMX…-BP (panel
mount), and all VMX…–E (NEMA 12 enclosed) versions.
Power Factor Correction Capacitors
Power factor correction capacitors can be connected to motors
controlled by
VMX Series
starters, however they must be off-line during
ramping. Connect PFC capacitors to the Line side of the starter with a
separate capacitor control contactor.
WARNING!
Never connect power factor correction capacitors on
the load side of the unit. The SCRs will be seriously
damaged if capacitors are located on the load side.
Grounding / Earthing
Connect the ground cable (PE) to the ground terminal as labeled “G” on the unit. Refer to the National Electrical
Code or your local code for the proper ground wire sizing and be sure that the ground connector is connected to
earth ground. In ungrounded systems, it is not necessary to connect a ground to the unit however local codes
should always be consulted.
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: [email protected]
