VYPER
™
VARIABLE SPEED DRIVE
INSTALLATION
100.200-IOM (SEP 13)
Page 26
EXTERNAL POWER AND CONTROL WIRING
External power and control signals must be brought in and
out of the Vyper
™
variable speed drive. The unit requires the
wiring to be properly installed to supply power to the unit
for processing. The Vyper
™
also outputs processed power
to the motor of a compressor package. The two connection
points are at the following locations:
INPUT POWER CONNECTION
For Remote-mounted units,
the Input power junction is located on the upper left side of
the cabinet. This location provides a junction for three power
cables, T1, T2, and T3. Incoming Power leads (See Figure 15)
must have their ends stripped of insulation for insertion in
the junction area.
WARNING
Be sure there is no power running through the leads during
installation!
The external power leads may be inserted into the top of the
circuit breaker and then fastened via a hex style wrench (See
Figure 16). In addition the grounding connection is adjacent
to the external power connections and located on the top
of the left wall of the cabinet. (See Figure 17)
Input Power Lead Torque Requirement
Wire Size
Material
Torque
4-4/0
Cu
275 in-lb
Figure 15 - Insulation stripped from power leads
OUTPUT POWER CONNECTION
(Remote Mount) The wire
leads from the motor must be prepared prior to installation.
The preparation involves stripping the lead insulation for the
motor to expose about ½” to 1” of the copper wire within
the lead. See Figure 15.
WARNING
Before working on the motor wiring, be certain that the
Drive has been powered down for at least five minutes.
This allows the internal capacitors/resistors to discharge
the DC bus and allow for safe maintenance of the unit.
Failure to do so may cause serious injury or death. Also
ensure that all power has been removed from the leads
while connecting to the Vyper
™
.
The motor leads must be brought in from the top of the
unit. Carefully remove the panel, which covers the motor
lead entry point, by removing the screws. Wires may then be
run into the interior of the cabinet. Be sure to leave enough
relief in the leads so no undue stresses are transferred to
the motor connection location in the interior of the unit.
The attachment points are T1, T2, and T3. They are labeled
in the body of the cabinet at the motor lead attachment
points. Insert the stripped connectors and tighten with a
small wrench. Connectors should not loosen when given a
moderate tug by hand.
Figure 16 - Fastening the power lead
Figure 17 - Grounding Lug
For remote-mounted units it is required that a dV/dt “snub-
ber” filter be installed between the Vyper
™
and the motor
to ensure a clean power signal into the motor. This filter is
required for all remote-mounted systems with power leads
between 3-50 feet in length.
OUTPUT POWER CONNECTION (Package Mount)
Package-mounted Vyper
™
drives have a different output
configuration than the remote-mount Vyper
™
. The Package-
mounted Vyper
™
uses 3/8" terminal lugs for the output power
connection to the compressor motor. Appropriate motor lead
hardware should be used to make the connections. The at-
tachment lugs are labeled T1, T2, and T3 and are located on
the back right wall of the interior of the Vyper
™
cabinet (See
Figure 18). The power wiring emerges from the rectangular
cutout on the back wall of the Vyper
™
cabinet (See Figure
19). Output power connections should be tightened as shown
in the table. An appropriate conduit must be connected to