Electrical Connections; Primary Lead Connections; Ground Connections; Secondary Control Wiring - Siemens SDV-4A Instruction Manual

Electrical Connections

Hazardous voltages.
Will cause death, serious injury, and
property damage.
De-energize and properly ground high
voltage conductors before working on or
near them. The user must adjust the breaker
height to ensure compliance with safety
codes for electrical clearance.

Primary Lead Connections

The primary leads should be brought down from above
the breaker if possible, with adequate clearance to other
parts, and with the proper supports so that the breaker
bushings are not subjected to excessive strains.
The leads should be sized to have a capacity at least equal
to the maximum operating current of the circuit and within
the rating of the breaker. Connections are to be made to
the bolted terminals of the bushings and must be securely
tightened to a clean, bright surface to assure good contact.

Ground Connections

Diagonally opposite grounding pads are provided for con-
necting the cabinet to ground, using at least a 4/0 AWG
conductor on each pad. A good low-resistance ground is
essential for adequate protection and for proper function-
ing of electronic components such as protective relays.
Provision for connecting to ground pads must be made in
such a manner that a reliable ground connection is ob-
tained. Consult latest National Electrical Code or National
Electric Safety Code for ground connection standards.

Secondary Control Wiring

All secondary control wiring installed by the factory is neatly
routed and secured in place. Make all field connections in
a similar manner. Check that the relay panel (if so equipped)
clears any additional wiring installed.
A conduit panel opening is provided in the bottom of the
relay and control compartment for the connection of con-
trol circuits. The control wires should be run separately
from high voltage wiring to prevent inductive coupling
between them and should be sized for full operating cur-
rent to avoid a drop in voltage below that specified on the
nameplate. All conduits should be sealed off at their en-
trance to the relay and control compartment.
Terminal blocks are provided inside the relay and control
compartment for the connections necessary for the con-
trol wiring, bushing current transformers and relay panel
(if so equipped). These terminal blocks are located inside
the control compartment immediately behind the control
compartment access door.
Connection diagrams are provided with each breaker and
will be found in the pocket inside the control compartment
door.
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