Description And Operation; Introduction; Interrupter Assembly; Figure 18. Typical Vcp-W Rear View Showing Vacuum Interrupters And Current Carrying System - Eaton VCP-W Series Instructions For Installation/Operation/Maintenance/Servicing

Instruction Booklet IB131006EN
Effective March 2019
TOC switches will also operate once the CONNECTED position is
reached, if TOC switches are provided in the structure. Remove the
levering-in crank at this point.
Close the circuit breaker. Any provided MOC switches will operate
and the motor closing springs will charge if control power is avail-
able.
Engage the levering-in crank. The slider can be pushed in to engage
the levering-in crank and the circuit breaker will automatically trip.
Lever the circuit breaker out approximately halfway towards the
TEST position.
Attempt to lift the circuit breaker lift/pull handle to pull the circuit
breaker out. The position withdrawal interlock will prevent lifting the
handle high enough to disengage the levering latch from the nut.
This prevents the circuit breaker from being pulled out.
Non-BPI pan assembly:
Engage the levering-in crank and the circuit breaker will automatically
trip and the MOC switches will operate if the circuit breaker cell is
equipped with MOC switches designed to operate in the TEST posi-
tion.
Lever the circuit breaker towards the CONNECTED position. As
the circuit breaker moves, protective compartment shutters will
automatically begin to open uncovering fixed primary contacts.
TOC switches will also operate once the CONNECTED position is
reached. TOC switches are provided in the structure. Remove the
levering-in crank at this point, if equipped with this option.
Close the circuit breaker. Any provided MOC switches will operate
and the motor closing springs will charge if control power is avail-
able.
Attempt to engage the levering crank. The slider cannot be pushed
far enough to engage the levering-in crank. Trip the circuit breaker,
engage the levering-in crank, and lever the circuit breaker out
approximately halfway towards the DISCONNECT/TEST position.
Attempt to lift the circuit breaker lift/pull handle to pull the circuit
breaker out. The position withdrawal interlock will prevent lifting the
handle high enough to disengage the levering latch from the nut.
This prevents the circuit breaker from being pulled out.
Attempt to close the circuit breaker by pushing the manual close
button. The circuit breaker will go trip free (springs discharge but
circuit breaker will not close). Lever the circuit breaker to the
DISCONNECT/TEST position. The secondary contacts will disengage
automatically.
BPI and non-BPI pan assembly:
If the extension rails are installed, then remove the extension
rails. Disengage the levering latch by lifting the handle on the
circuit breaker and attempt to pull the circuit breaker out. The
circuit breaker will not move out more than two inches beyond the
DISCONNECT or DISCONNECT/TEST position. Push the circuit
breaker back to the DISCONNECT or DISCONNECT/TEST position.
Engage the extension rails. Once again disengage the levering
latch and pull the circuit breaker out. The circuit breaker will trip,
close and trip as it comes out on to the extension rails from the
DISCONNECT or DISCONNECT/TEST position.
Automatic/manual hybrid secondary (optional - Figure 46):
It will function the same as the Non-BPI pan assembly above due to
the replacement of the "L " bracket with the "Z" bracket.
THE INTERFACE CHECKS OUTLINED IN THIS MANUAL AND THE MANUAL
PROVIDED WITH THE ASSEMBLY STRUCTURE ARE INTENDED TO VERIFY
SAFE AND PROPER OPERATION. IF OBSERVED CONDITIONS ARE NOT AS
DESCRIBED, CONTACT EATON FOR ASSISTANCE.
36
EATON www.eaton.com
NOTICE
operation, and maintenance of type
VCP-W vacuum circuit breakers

5. Description and operation

5.1 Introduction

Type VCP-W, VCPW-SE, VCP-WC, and VCPW-ND vacuum circuit
breakers are horizontal drawout designs for use in metal-clad switch-
gear compartments. Most ratings can be stacked two high in a
vertical section resulting in a considerable savings of floor space.
Vacuum interrupters are used with all circuit breakers to close and
open the primary circuit. All VCP-W circuit breakers are operated by
a front mounted spring type stored energy mechanism
(Figure 5). The stored energy mechanism is normally charged by an
electric motor, but can be charged manually with the manual main-
tenance tool. Since the same basic, front accessible mechanism is
used for all VCP-W circuit breakers, a minimum investment in spare
parts is required.
The primary insulation used with Type VCP-W circuit breakers is
flame retardant and track resistant glass polyester except for the
Type VCPW-SE circuit breaker. The VCPW-SE special environment
circuit breaker design utilizes cycloaliphatic epoxy for its primary
insulation. "Fast On" type secondary control terminations are used
on Types VCP-W, VCP-WC, and VCPW-ND circuit breakers, while the
Type VCPW-SE circuit breaker utilizes ring type secondary control
terminations.
The rest of this section describes the overall operation of the VCP-W
circuit breaker as well as the function and operation of all major
sub-assemblies and/or parts. Keep in mind that VCP-W will be used
throughout the text when referring to any one of the three types
of circuit breakers, unless there is a specific difference between
VCP-W, VCPW-SE, VCP-WC, and VCPW-ND.

5.2 Interrupter assembly

Vacuum interrupters are mounted vertically and supported from the
fixed stem which is clamped to the top conductor. The exclusive
current transfer system consists of a series of plated, high-
conductivity copper leaf conductors that are pressed on the movable
interrupter stem. This design provides a multipoint contact resulting
in low electrical and thermal resistance. Utilizing this non-sliding
current transfer system between the movable stem and the breaker
main conductor eliminates the need for maintenance (Figure 18).
Multiple finger, floating type primary disconnecting contacts at the
ends of the top and bottom conductors provide a means for
interfacing with the primary conductors mounted in the switchgear
(Figure 18).
Figure 18. Typical VCP-W rear view showing vacuum interrupters
and current carrying system.
Instructions for installation,