GE 15LSWGR901, Operation & Maintenance Manual

Page: 182 / 188

6
5.
INTERLOCKS
5.1 Current Rating Interlock
Each Manual Ground and Test Device is equipped with
a current rating interference plate (15) Fig. 2, which
allows the properly rated Manual Ground and Test
Device to enter the metal-clad unit. Refer to GEK
90209 “Metal Clad Switchgear Types VM-4.16 and VM-
13.8” for the operation of this interlock in the metal-
clad equipment. Two nameplates on the device give
the current rating. One on the front cover and the
other is on the right hand side of the lower frame.
CAUTION:
Make certain the current rating of the
Manual Ground and Test Device matches the current
rating of the compartment being tested. If the current
ratings do not match and the Ground and Test Device
is forced into the compartment by tampering with the
interlock, serious injury could result to the operator.
5.2. Compartment Elevation Interlock
A Compartment Elevation Selector Lever (3) Fig. 1, on
the front of the Manual Ground and Test Device is
used to select which compartment is to be tested.
When the lever is” Up” the device can enter the upper
compartment. When the lever is “Down” the device
can be used in lower
compartment. The Selection
Lever distinguishes between the upper and lower
compartment by operating a dent (4) Fig. 1, which
contacts the interference plate in metal-clad unit. This
is same plate as is used for the Current Rating
Interlock.
The Elevation Selector Lever also operates the
”Compartment Indicator” label (8) Fig. 1, and “Bus and
Line/Load Indicator” label (7) Fig. 1. This means that
after the Compartment Elevation position has been
set, the upper and lower sets of extension bars are
identified.
CAUTION: This interlock is provided as a safeguard for
the operator so that the terminals being tested are
labeled. It is the responsibility of the operator to
determine which terminals should be exposed for
particular test. If this interlock is forced, the terminals
may be mislabeled so that serious injury could result
to the operator.
6.
INDICATORS
6.1. Indicator Rods
Indicator rods (2) Fig. 1, are provided at the front of the
Manual Ground and Test Device to indicate when
Connection Bars (1, 2, 3) Fig.2, are attached to the
Extension Bars (5) Fig. 2. The Indicator Rods run
parallel to the Extension Bars. They are spring
mounted in such a way that when the Connection Bar
is attached to the Extension Bar, the Indicator Rod
must be moved forward towards the front of the
device. The Connection Bar holds the Indicator Rod in
the extended position. When the Connection Bar is
removed a spring returns the Indicator Rod to its
rearward position.
CAUTION : The Indicating Rods are not interlocks to
prevent unsafe operation. As the name implies, the
rod indicates if a Connection Bar is attached. It is the
responsibility of the operator to check the primary
connections to make certain they match the desired
testing condition. Forcing the Indicating Rod could
indicate an incorrect testing condition and result in
serious injury to operator.
6.2. Protective Shutter
A Protective Shutter (6) Fig. 1, is provided to cover the
Extension Bars that do not have the Connection Bars
attached. This Shutter is manually positioned up or
down by hand tightening screws (9) Fig. 1, located on
rear of the front cover
. These screws are located on
the rear so that they will be inaccessible when the
Manual Ground and Test Device is in the
compartment. In this way the exposed Extension Bars
cannot be uncovered unless the device is removed
from the metal-clad unit.
When the Indicator Rods are extended forward, the
Indicator Rods will interfere with motion of the shutter
so that it will not completely cover these terminals.
This provides another indication as to which studs
Connections Bars are attached.
CAUTION : The Protective Shutter is not an interlock to
prevent unsafe operation. It is provided as a
convenience to the operator as a cover for the
primaries not under test. It is the responsibility of the
operator to check the primary connections to make
certain they match the desired testing conditions.
Tampering with shutter or partially covering the
terminals could result in an unsafe testing condition
and cause serious injury to the operator.