Instrument Transformer, Div of GE FT, RT Data Sheet

FT & RT

TEST SWITCHES

KEY BENEFITS

The FT Switches and FT Test Plugs have all the features necessary for applications involving the measurement of individual
currents and voltages to facilitate testing of substation instrumentation and protection devices from the front of the panel.
The make before-break current short circuit feature allows test personnel the convenience of isolating equipment from current
transformer circuits.

Voltage measurements can be made directly on the FT Switch without disturbing existing connections. There is a test clip provision
located on the top of each pole that allows connection with standard spring clip test leads.

APPLICATIONS

FT Test Switches:

The ITI FT Test Switches and Test Plugs provide a safe, simple, immediate and reliable method to isolate equipment and measure
system current and voltage during field testing and commissioning.

RT Rack Mount Test Switches:

RT Switch assemblies for rack and switchboard mounting permit convenient isolation of switchboard relays, meters and
instruments. RT racks allow quick and easy multi-circuit testing by conventional test methods and for faster installation into
switchgear.

FEATURES

FT Test Switch:

• Built with a maximum of ten individual poles, of potential,

current, and current shorting switch units

• Switches can be assembled in a variety of different

arrangements to match customer requirements

• FT Test plugs are used in conjunction with the FT Switches

to enable easy measurement, calibration, verification or
maintenance of relays, meters and instruments

• UL / cUL E101598

Protection:

• With the cover in place, a meter type seal can be placed

through either of the cover studs of the FT Switch to
prevent unauthorized access

• Standard black cover mounts only when all switches are

in the closed position

• A clear cover is available that can be installed with the

switchblades in the open or closed position

Energy

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RT Rack Mount Test Switches:

• RT Switches accommodate three FT switches mounted

on a 19” wide steel mounting panel (Brushed aluminum
available)

• Provides up to 30 terminals with three FT combinations

• Color and finish can be customized

• Optional rack heights for label applications

• Each panel is supplied with the hardware to mount the RT

assembly to the 19” rack enclosure

• The RT assembly will support an FT style test plug

• Full-length clear cover is standard. Full length black cover,

individual clear covers, and individual black covers are
available

• UL / cUL E101598

Protection:

• Once the full-length clear cover on the RT switch is

installed, it prohibits access to some of the rack mounting
screws

• Individual clear covers offer additional protection

consistent with common testing procedures to ensure
only correct switch is exposed during testing

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FT & RT Test Switches

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FT Specifications

Rating

The standard FT switch is rated at 600 volts and 30 Amps. The
Switch meets or exceeds all requirements of ANSI / IEEE Standard
C37.90 and is UL and cUL recognized.

Mounting

FT Switches are designed for semi-flush mounting on the front of
switchboard panels, facilitating inspection and accessibility.

Drilling Plan - Inches

Fasteners

Captive fasteners are made of molded plastic with a threaded brass
insert for easy cover installation and removal.

Switch Poles

FT Switches are available in configuration of 1 to a maximum of
10 individual poles or switch units. Each pole identified by letter (A
thru J), which is visible along the top of the base from left to right.
The individual switch units are of knife blade type. There are three
different types of switch units available: potential, current, and
current shorting.

Blade assembly of two position pole “C-C” (outside of base)

FT Switch Construction

The base of the FT Switch is made of black electrical grade plastic
material which provides a tough insulated enclosure. Barriers are
molded into the base (front and rear) to separate the switch units
from one another. The barriers provide insulation between poles and
ample space between terminals.

Cover

FT Switches come with a black opaque cover or a clear see-through
cover. Switch covers provide a tough insulated enclosure for the
switch and are made from plastic material. The clear cover affords
the user the option of leaving switch handles in the open position
and replacing the cover while maintaining the provision for a meter
type seal when some or all switch handles are in the open position.
This feature allows the user to service electrical equipment while still
complying with OSHA lockout/tag-out procedures. The clear cover
can be ordered separately for retrofit to existing FT Switches. RT
racks come standard with a full length clear cover and can be sealed
with a meter seal.

Switch Handles

Switch handles are made of a molded plastic insulating material
typically black in color. Red handles can be supplied by replacing
the “P” with “T” for potential handles and replacing “C” with “R” for
current handles. Additional colors are available upon request.

Each handle has a dovetail indentation to hold a circuit identification
label (by others). Knife blade switches can be operated independently
or ganged together with a horizontal interlocking bar (see page 4).

A hole runs through the middle of each switch handle to allow
insertion of interlocking bars. 2 to 10 switch handles can be
mechanically tied together.

Terminals

Connection terminals are located at the rear of the switch and can
be either screw or stud type. Terminals are numbered 1 thru 20 for
easy identification. Each pair of numbered terminals is associated
with a matching pole designated by a letter on the front of the switch.

FT switch terminals 1 thru 20 (rear view)

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FT & RT Test Switches

FT Test Plugs

The Test Plug with a maximum of 10 positions is designed to match
the pole configuration of specific styles of FT Switches. Not every
switch configuration is suitable to accept a Test Plug. For available
styles, see switch selection tables.

10-Pole “In-Service Series” Test Plug Inserted into FT Test Switch

In-Service Series Test Plug

Provision is made only on current poles with shorting springs to
automatically short-circuit current transformer circuits when the
knife switches are opened prior to inserting the Test Plug.

This Test Plug is typically used to connect devices measuring the
currents and voltages being applied to the switchboard relays, meters
and instruments without interrupting or short-circuiting the circuit.
Only the current test switches with the current jack must be opened
before inserting the Series Test Plug. Connections to the test plug must
be made before inserting the test plug into the FT Switch. Before
inserting the Test Plug, all switchblades that are opposite bi-conductor
paddles must be placed in the full open position.

Single Pole Current Test Plug with Open
Secondary CT Protection

• HelpsreduceriskofhighvoltagesassociatedwithopenCT

secondary

• Reducesrisksduetooperatorerror,incorrectequipmentsettings

and deviation from correct test procedures

• Addssafetyforoperatorsandtechnicians

• Providesasimple,fastandreliablemethodtoisolateandservice

installed meters, relays and CT’s

How it works

If a CT opens during operation:

• TestplugshortstheCTsecondarytohelpreducetheriskofover-

voltage conditions for personnel and equipment

• RedLEDprovidesvisualindicationofanopenCTsecondary

circuit causing an over-voltage condition

Features

• Ergonomichand-helddesignallowsin-servicecurrent

measurement with an ammeter

• Ratings:600V,20Acontinuous

• LEDindicationofover-voltageprotectionoperation

• DesignedforusewithITIFTtestswitch

• AvailablewithorwithoutCTopensecondaryprotection

• ANSI/IEEEC37.90standards

10-Pole “In-Service Series” Test Plug

Ordering Information:

Catalog Number Open Circuit CT Protection

SPTP-01 Yes
SPTP-02 No

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FT & RT Test Switches

Non Standard FT Style Switch Selector

Step 1

• TheSwitchbodycansupport1to10polesinslotmarkedA

through J

• Enteraletterfromthelegend.Leaveunusedslotsblank

Position:

Excample:

P C - - C R C R - - R P P P

Legend:

P=Potential, Black

T=Potential, Red

C=Current, Non-shorting, Black

C-C or C-C-C- or C-C-C-C = Current , Shorting, Black

R = Current, Non-shorting, Red

R-R, R-R-R, R-R-R-R = Current, Shorting, Red

Additional colors available - See page 11

(Note: Some functions will require more than one slot in the
switch body)

Step 2

(Optional)

If a tie bar is required then check this box
and draw a dark heavy line over the poles to be joined.

(In the example shown in Step 1 positions H, I and J will operate
together.)

Step 3

Select a cover style

Clear (installs over open and closed switch blades)

Black (installs over closed switch blades only)

Step 4

Select a rear terminal type

Screws (Standard) Studs (Optional)

FACTORY USE ONLY

Catalog Number Assignment

444