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Instruction Book IB182312EN June 2016 www.eaton.com
50/75/150 VCP-W
Selectable Ground and Test Device
SECTION 4: DESCRIPTION AND OPERATION
The SG&T is a draw out device that can be inserted into a circuit
breaker cubicle in the same manner as the 150 VCP-W Circuit
Breaker. It can be ordered as a single terminal device or a double
terminal selectable ground and test device. Each terminal is isolated
from each other and the ground bus connections by insulating
barriers. The upper and lower terminals are accessible upon opening
the respective front hinged door. The ground connection is easily
accessible on the lower front section of the device (Figure 3.3.a).
Interchangeable primary disconnects allow the SG&T device to be
converted between the available amperes for this device. (1200A /
2000A and 3000A)
WARNING
IT IS MOST IMPORTANT THAT THE LOAD OR LINE TERMINALS BE
CORRECTLY IDENTIFIED FOR EACH COMPARTMENT BEFORE USING THIS
DEVICE.
Type 150 VCP-W Selectable Ground & Test devices are also available
with either the upper or lower terminals only.
4.1 INSULATING BARRIERS
Insulating barriers are GPO-3 glastic material used to isolate the
primary terminals from each other and the ground connections.
4.2 BUSHINGS AND DISCONNECTING CONTACT
ASSEMBLIES
The upper and lower bushings, which are the primary circuit
terminals of the selectable ground and test device, consist of
silver plated insulated conductors. Multiple finger type primary
disconnecting contacts at the ends of the conductors provides
means for connecting and disconnecting the SG&T device to the bus
terminals in the switchgear compartment. (Figure 3.5)
4.3 GROUNDING CONTACTS
The grounding contact is an assembly of spring-loaded fingers,
which ground the device by engaging the switchgear cell grounding
bus when the SG&T device is levered into the “connect” position.
The ground contact is located at the lower section of the device, on
the truck, and visible from the front of the device. (Figure 3.3.a)
4.4 BREAKER-CELL CODING PLATES
NOTICE
CODE PLATES WILL BE SUPPLIED PER SWITCHGEAR REQUIREMENTS AND
THEREFORE AMPERAGE/RATED SHORT-TIME CURRENT ARRANGEMENTS
WILL NOT BE COVERED IN THIS MANUAL. DETAILED INFORMATION
ON THE SPECIFIC CODE PLATE OPTIONS WILL BE PROVIDED WITH THE
CUSTOMER ORDER.
This is a combination of a notched plate in the cell and interference
bars on the breaker, so that only appropriately rated breakers can be
put into the cell (Figure 3.3.a).
WARNING
FOR 1200A/2000A/3000A UNIVERSAL SELECTABLE GROUND & TEST
DEVICES A CODE PLATE HAS BEEN FACTORY INSTALLED TO MATCH THE
RATING OF THE FACTORY-INSTALLED PRIMARY DISCONNECTS. ENSURE
THAT THE CORRECT PRIMARY DISCONNECTS AND CODE PLATES HAVE
BEEN INSTALLED FOR THE CORRECT APPLICATION.
4.5 CELL POSITION DESCRIPTION
Position A: This is the withdrawn position. In the withdrawn position,
the selectable ground and test device is out of the cell. The racking
handle is not required for this position.
Position B: As the SG&T device is pushed into the cell, it will reach a
mechanical stop. This is the “disconnect” position.
Position C: Continue rotating the racking handle until the rotating
handle turns freely, and the SG&T device stops moving. The device
will have reached the “connect” position. (Figure 5.11) Remove the
racking handle.
Figure 4.1. Installed Code Plate (1200A/50kA Unit Shown)
Figure 4.2. Primary Disconnect Installed (3000A)
