DE-STA-CO VARI-PAK DC CONTROL - Manual (Page 11)

Failure to follow the Safety Warning Instructions may result in electric shock, fire or explosion.
Do not fuse neutral or grounded conductors. Note: See section V, Fusing, on page 10. A
separate AC line switch, or contactor, must be wired as a disconnect switch, so that the contacts
open each ungrounded conductor. (See figure 4, below for AC Line and Armature Connection.)
Note: Do not bundle AC or motor leads with logic leads or erratic operation may occur.
1. Twist logic wires (speed adjustment potentiometer or voltage signal input wires) to avoid
picking up electrical noise. If wires are longer than 18”, use shielded cable.
2. You may have to earth ground the shielded cable. If noise is coming from devices other
than the drive, ground the shield at the drive end (ground screw in enclosure). If noise is
generated by a device on the drive, ground the shield at the end away from the drive. Do
not ground both ends of the shield.
3. Do not bundle logic wires with power carrying lines or sources of electrical noise. Never
run speed adjustment potentiometer or voltage signal input wires in the same conduit as
motor or AC line voltage wires.
4. Connect earth ground to the earth ground screw provided in the enclosure. (See figure
4 for ground screw location.)
Two .875” (22.2 mm) knockout holes are provided for a standard 1/2” knockout connec-
tor (not supplied) for wiring. A plug is provided if only one knockout is required. Be sure
to use suitable connectors and wiring that is appropriate for the application.
A. AC Line – Connect AC Line to ter-
minals L1 and L2. (Be sure the
control model and rating match
the AC line input voltage. See
table 1, on page 3.)
B. Motor Armature – Connect motor
armature to terminals A1 (+) and
A2 (-). (See table 1, on page 3).
WARNING! Do not wire switches
or relays in series with the arma-
ture. Armature switching can
cause catastrophic failure of
motor and/or control. Do not
bundle AC line and motor wires
with other wires (e.g. potentiometer, analog input, Run, Jog, Stop, etc.) since errat-
ic operation may occur. Do not use this control on shunt wound motors.
C. Ground – Be sure to ground (earth) the control by connecting a ground wire to the Green
Ground Screw located to the right of the terminal block. Do not connect ground wire
to any other terminals on control.
D. Main Potentiometer – The control is supplied with the main potentiometer prewired.
However, the control can also be operated from a remote potentiometer, or from an iso-
lated analog voltage for voltage following. To operate from an external source remove
white, orange and violet potentiometer leads from terminals P1, P2 and P3. The leads
may be taped and left in the control. The potentiometer itself may be removed, if a seal
is used to cover the hole in the front cover. Note: Use shielded cable on all connec-
tions to P1, P2, or P3 over 12” (30cm) in length. See section IV, items 1-4.
9
TABLE 5 – TERMINAL BLOCK WIRING INFORMATION
TB2
A1 A2 L1 L2
A
M
AC LINE
INPUT
Do not connect
ground wire to any
other terminal
Earth
Ground
MOTOR
FIGURE 4 – AC LINE & ARMATURE CONNECTION
Terminal Block
Designation
Connection
Designation
Supply Wire Gauge*
Maximum
Tightening Torque (in-lbs)
Minimum Maximum
TB2 A1, A2, L1, L2 22 12 12
TB1 Logic Connections 24 14 3.5
*Use Cu wire only (AWG)