INSTALLATION
(continued)
1--2
Connecting Power Conductors
A
Wiring Diagram
is furnished with the ATB. All wiring
must be made in accordance with the local codes. After
the power cables have been tested, connect them to the
appropriate terminal lugs on the Bypass Switch as shown
on the wiring diagram provided with this ATB. Make
sure that the lugs provided are suitable for use with the
cables being installed.
Standard terminal lugs are
solderless screw type and will accept the wire sizes listed
on the drawings provided with the ATB. Be careful when
stripping insulation from conductors; avoid nicking or
ringing the conductor. Remove surface oxides from
conductors by cleaning with a wire brush. Follow
conductor manufacturer’s instructions when aluminum
conductor is used. Apply joint compound to conductor,
then carefully wipe away excess compound. Tighten the
cable lugs to the torque specified on the rating label.
Be sure that the Normal and Emergency power
connections are in proper phase rotation.
!
Figure 1–1. Bus tie plates (top view).
See job specific drawings supplied with ATB.
!
Bus Connections
If bus connection is used, use SAE grade 5 hardware to
connect bus to appropriate terminal plates on bypass
switching device. Wipe off bus surfaces before they are
joined. If bus is dirty, gently clean surfaces with a
non-flammable solvent. Avoid touching cleaned surfaces.
Do not breathe cleaning solvent vapors.
!
Use SAE grade 5 hardware and tighten the bolted joints
to the torque specified in Table 2-1.
The reliability of the connection depends
on how clean and how tight the joint is.
!
Table 2-1. Tightening torque values for bolted joints.
Bolt Diameter
(Grade 5 hardware)
in inches
Recommended
Tightening Torque
in foot pounds
5/16
12
3/8
20
1/2
50
5/8
95
3/4
155
Harnesses
All internal connections are made at the factory. The
bypass switch, transfer switch, and control panel are
joined together by an interconnecting wire harness. The
disconnect plugs are already engaged on enclosed
switches. For open–type switches, the plugs must be
engaged after installation is completed. Align harness
plugs with sockets in the control and push them together
until they are secure.
Engine Starting Contacts
and Auxiliary Circuits
The engine control contact signal connections and
auxiliary circuits are located on terminal block TB as
shown on the
Wiring Diagram
provided with the ATB.
Connect the signal wires to the appropriate terminals.