GE ZTSCT User Manual

GE Zenith Controls

71R-5000A

11/04

ZTSCT/ZBTSCT Series
Closed Transition Transfer
& Transfer Bypass - Isolation Switches
100-4000 Amps

Operation and Maintenance Manual

Page

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

Equipment Inspection and Storage . . . . . . . . . .11

Final Equipment Inspection . . . . . . . . . . . . . . .11

Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

Power Connections . . . . . . . . . . . . . . . . . . . . . . .12

Engine Start Control Connections . . . . . . . . .12-3

Initial Energization . . . . . . . . . . . . . . . . . . . . .13-4

Control Connections . . . . . . . . . . . . . . . . . . . . . 5

Entelli-Switch 250 Microprocessor Controller . . . . .16

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

LCD & Keypad . . . . . . . . . . . . . . . . . . . . . . . . . .17

User Setting for Voltage & Frequency . . . . . . .1 8

Accessory Group Packages. . . . . . . . . . . . . . . . . 9

Accessory Definitions . . . . . . . . . . . . . . . . . . 10-13

How to Set the System Clock . . . . . . . . . . . . . . 13

CDT One Event Timer Exerciser . . . . . . . . . . 14

CDP Clock Exerciser . . . . . . . . . . . . . . . . . . . . 15

User Setup - CFG Menu . . . . . . . . . . . . . . . . . . 16

User Setup - SET Menu . . . . . . . . . . . . . . . . . . 17

User Setup - System Info . . . . . . . . . . . . . . . . . 18

Page

Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . .119

Test Options . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

ATS Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . .120

Open Transition . . . . . . . . . . . . . . . . . . . . . . . . 20

Closed Transition . . . . . . . . . . . . . . . . . . . . . . . 21

Emergency Service Procedure

for Extended Parallel Time . . . . . . . . . . . . . . . 22

Sequence of Operation . . . . . . . . . . . . . . . . . . . . . . 23

Open Transition . . . . . . . . . . . . . . . . . . . . . . . .123

Closed Transition . . . . . . . . . . . . . . . . . . . . . . . 24

Bypass-Isolation Operation . . . . . . . . . . . . . . . 25

100-400 AMP . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

600-1200 AMP . . . . . . . . . . . . . . . . . . . . . . . . . . 27

1600-4000 AMP . . . . . . . . . . . . . . . . . . . . . . . . . 28

Controls Power Supply (CPS) . . . . . . . . . . . . . . . . . 29

Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130

Troubleshooting & Diagnostics . . . . . . . . . . . . . . . . 31

Maintenance and Testing . . . . . . . . . . . . . . . . . . . . . 32

Inspection and Cleaning . . . . . . . . . . . . . . . . . 32

Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132

Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132

Table of Contents

Authorized Service

For GE parts and service, call: 773 299-6600

Introduction

GE Zenith Transfer Switches are used to provide a continuous source of power for lighting and other critical loads by
automatically transferring from source 1 power to source 2 power in the event that source 1 voltage falls below preset limits.

Voltage sensing and system control is performed via a state-of-the-art microcontroller located on the cabinet door.
It is designed to give highly accurate control of the transfer switch system.

All GE Zenith transfer switches are designed for use on emergency or standby systems, and are rated for total system or
motor loads. Transfer switches are UL Listed under Standard 1008 and CSA Certified under Standard C22.2 No. 178 and
IEC Listed under Standard 947.

NOTES: A protective device such as a molded case circuit breaker or fused

disconnect switch MUST

be installed on both sources of incoming

power for circuit protection and as a disconnection device.
All references made within this manual about the term “S1” or

“Source 1” relate to a Normal Power Source. All references made
about the term “S2” or “Source 2” relate to an Emergency
or Alternative Power Source.

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

Safety

Each GE Zenith transfer switch is factory wired and
tested. A complete information package is furnished
with each switch which includes:

a. Sequence of operation.
b. Description and operation of

all accessories supplied.

c. Power panel connection diagram

and schematic.

d. Description and identification of

all customer field connections.

Installation of GE Zenith transfer switches includes:

a. Mounting the transfer switch cabinet.
b. Connection of Source 1, Source 2,

and Load cables or bus bars.

c. Connection of external control

circuits as required.

Mounting

Adequate lifting means must be used to mount the
transfer switch into place. The recommended method for
moving the transfer switch using the lifting eyes, where
supplied, and a spreader bar is illustrated in Figure 1.
Enough room should be allowed to open the cabinet
doors fully for inspection and servicing of the switch per
NEC and local codes.

The safe operation of your switch is GE Zenith’s focus.
The proper storage, installation, operation and mainte­nance will help increase the life of the switch.

Equipment Inspection
and Storage

Once you have received the transfer switch, inspect
it for any damage. This includes damage to the
enclosure, power panel, control panel and wiring
harness. If any damage is found or suspected, file a claim
as soon as possible with the carrier and notify the nearest

GE Zenith representative.

Before installation, if it is necessary, store the transfer
switch in a clean dry place, protected from dirt and water.
Provide ample air circulation and heat, if necessary, to
prevent condensation.

5% to 95%
(non-con­densing)

-30°C to
+75°C
(-22°F to
+167°F)

40-400

AMP

(molded shell)

-20°C to +65°C
(-4°F to +149°F)

40-4000

AMP

(all other frame
and panel types)

-20°C to +60°C
(-4°F to +140°F)

Operating
Storage Temperature
Temperature (Ambient): Humidity

Final Equipment Inspection

Prior to energizing the transfer switch:

1. Remove any debris incurred, with a vacuum, due
to shipment or installation.

2. Verify that all cabled connections are
correct and that phase rotation of both sources
match.

3. Check engine start connections.

4. Verify the correct connection of all
control wires.

5. Check settings of all timers and adjust
as necessary.

6. Adjust any optional accessories as required.

7. Check the lug torque values of the power
connections.

NOTE: Lug torque values are specified

in table 2 on pg.2.

8. Make sure that all covers and barriers are
installed and properly fastened.

NOTE: Power panels ship from GE Zenith

in Source 1 Position.

Before drilling conduit entry holes or any

accessory mounting holes, cover and protect

the switch and control panel to prevent dirt

and metal fragments from entering the
mechanical and electrical components.

Failure to do so may result in

damage and malfunction of the switch.

DANGER

HAZARDOUS VOLTAGE

(Can Cause Severe Injury or Death)

Turn OFF all power before installation, adjustment, or removal of transfer switch or any of its components.

CAUTION

Due to hazardous voltage and current, GE Zenith rec-

ommends that a

GE Zenith Certified technician or a

qualified electrician must perform the

installation and maintenance of the switch.

WARNING

Do not use a blower since debris may

become lodged in the electrical and

mechanical components and cause damage.

CAUTION

2 GE Zenith Controls

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

Installation

Table 2

Tightening Torque for Lugs

Socket Size

Across Flats

Torque

Lb. - In.

Lb. - Ft.

45

1/8

4

100

5/32

8

120

3/16

10

150

7/32

12

200

1/4

17

275

5/16

23

375

3/8

31

500

1/2

42

600

9/16

50

D

CABINET

LIFTING EYES

SPREADER BAR

H

45°

Figure 1

Power Connections

GE Zenith transfer switches are supplied with UL listed
solderless screw type terminals as standard for the
Source 1, Source 2 and Load power connections.
Table 1 lists the number and sizes of cable lugs supplied
as standard for each switch amp rating.

Connect the Source 1, Source 2, and Load conductors
to the clearly marked terminals on the transfer switch.
Remove surface oxides from cables by cleaning with a
wire brush. Verify that all connections are correct before
tightening the lugs. All cable lug connections must be
tightened to the proper torque values as shown in
Table 2.

NOTE

: Do not run cables or wiring behind

front-connected transfer switches.

Engine Start
Control Connections

Engine-start control wires connect to control terminals
beside the MX250. Engine start terminals are indicated by
a schematic symbol (the symbol indicates the contact
state for a de-energized normal source). Figure 3 shows
the engine-start contacts.

Make all other necessary control connections to the con­trol panel terminal blocks per the schematics supplied
with the ATS.

NOTE: All control wires (18-12 AWG) must be

torqued to 19 in/lbs.

NOTE

: When lifting the switch using a spreader bar,

height H must be equal to half of distance D.

Table 1

Power Connections: Screw Type Terminals for External Power Connections

Switch Size

(Amps)

40

80
100
150

200, 225, 2500

260, 300*, 400

600

800, 1000, 1200

Source 1, Source 2 & Load Terminals

1 #8 AWG to 1/0

Cable Per Pole Range of Wire Sizes

1 #8 AWG to 1/0
1 #8 AWG to 1/0
1 #8 AWG to 3/0
1 #6 AWG to 250 MCM
1 #4 AWG to 600 MCM
2 #2 AWG to 600 MCM

4 #2 AWG to 600 MCM

Neutral Bar (When Required)

3 #8 AWG to 1/0

No. of Cables Range of Wire Sizes

3 #8 AWG to 1/0
3 #8 AWG to 1/0
3 #8 AWG to 300 MCM
3 #6 AWG to 300 MCM
3 #4 AWG to 300 MCM
8 #2 AWG to 600 MCM

12 #2 AWG to 600 MCM

1600, 2000

2600, 3000, 4000

Line, Load and Neutral terminals are located in the rear of switch

and arranged for bus bar locations

DANGER

HAZARDOUS VOLTAGE

(Can Cause Severe Injury or Death)

Turn OFF all power before installation, adjustment, or removal of transfer switch or any of its components.

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

Installation

(cont’d)

Engine Start
Control Connections

The engine-start terminals are clearly identified by a
label on the microcontroller backplate. In the case of
manual transfer switches, or in other applications not
requiring the microprocessor, clearly marked terminal
blocks are provided in the upper left corner of the con­trol panel for the engine start control wires.

Figure 3 shows location of engine start connections
for Bypass Isolation Transfer Switch. Figure 6 (pg.5)
shows location of engine start connections for
Automatic Transfer Switch.

Terminals for field connections to the A3 Source 2
auxiliary contacts and the A4 Source 1 auxiliary contacts
are also provided. These terminals are clearly marked
and appear on the side of the power panel. On 400
amp metal frame units these terminals appear on
the bracket above the operator handle.

Initial Energization

Before proceeding, refer to the information package
supplied with the ATS and read and understand the
information on all accessories provided.

1. Unlock the enclosure.

2. Open the enclosure.

3. Verify the correct system voltage.

NOTE: The equipment rating nameplate on

the transfer switch lists the voltage.
See Figure 4.

4. Close Source 1 circuit. breaker.

NOTE

: The controller will illuminate Source 1

Available LED if proper voltage is sensed.

5. Verify the phase to phase voltages at Source 1
line terminals.

6. Close Source 2 circuit breaker.

7. Start the generator’s engine.

NOTE

: The controller will illuminate Source 2

Available LED when preset voltage
and frequency levels are reached.

8. Verify the phase to phase voltages at Source 1
line terminals.

9. Verify that the phase rotation of Source 1
is the same as the phase rotation of
Source 2.

10. Shut down the generator’s engine.

11. Place the starting control in the Automatic position.

12. Complete the visual inspection of the transfer switch.

13. Close the enclosure.

14. Lock the enclosure.

Figure 4

Figure 2

Figure 3 (Typical)

SERIAL NUMBER:

RA

TING

: VOLTS -

AMPS -

SYSTEM VOLTS:

MODEL NUMBER:

HZ -

PHASE -

GE Zenith Controls

DANGER

HAZARDOUS VOLTAGE

(Can Cause Severe Injury or Death)

Turn OFF all power before installation, adjustment, or removal of transfer switch or any of its components.

E

CAUTIONS

Certain accessories, per specific

schematics, can inhibit automatic transfer.

Engine Gen-Set could start when

engine control wires are attached.

4

5

6

1

P Relay

2

(Engine Start)

3

Contact rating is
10 Ampere at 120VAC
or 28VDC Gold plated

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

Installation

(cont’d)

NOTE

: When the voltage and frequency

reach preset values, the Source 2
Available LED will illuminate.

7. Verify the phase to phase voltages at Source 2

line terminals.

8. Verify that the phase rotation of

Source 2 is the same as the phase
rotation of Source 1.

9. Shut down the generator's engine.

(Place in Automatic Mode.)

NOTE

: Source 2 Available LED

will turn off.

NOTE: The engine generator will continue

to run for the duration of Source 2
Stop Delay Timer.

10. Place the disconnect switch to

ENABLE.

11. Complete the visual inspection of the

transfer switch.

12. Close the enclosure.

13. Lock the enclosure.

Figure 5 – LCD and keypad

Initial Energization (cont’d)

After all options and accessories are checked and
verified, follow these steps to set up the ATS. Refer to
Entelli-Switch 250 display Figure 5. The annunciation
LEDs illuminate to indicate (1) source availability,
(2) ATS position, and (3) Entelli-Switch 250 control
function (timing).

1. Unlock the enclosure.

2. Open the enclosure.

3. Place the Disconnect Switch in the Inhibit.

NOTE: This step is only performed if the

“DS” Option was purchased.

4. Close the external (up-stream) Source 1
circuit breaker.

NOTES: Source 1 Available and Source 1

Position LED

’s will illuminate.

If Source 1 Available

LED

does not
illuminate, verify that Source 1 Voltage
is above the preset restore value.

The Gen-Set will start and run while
Source 2 stop Delay Timer is timing.

5. Close the External (up-stream) Source 2 line
circuit breaker.

6. Start the engine generator in

MANUAL mode.

When performing a hi-pot or

dielectric test on the power section,

DISCONNECT the control panel plugs from

the microprocessor to avoid potential damage.

S1 OK

21:56

MON 23 APR 2002

MORE TEST

WARNING

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

Installation (cont’d)

A complete information package is furnished with
each transfer switch including a complete connection
diagram and schematic which details all necessary
control circuit field connections.

The engine start control wires connect to the
engine start relay terminals located to the left
of the microprocessor. Figure 6 shows the location
of these terminals.

To R/T Box

To Power

Panel

Input/Output

Connectors

to I/O Modules

Engine Start
Connections

Clock Program
Backup Battery

Remove protective
strip to enable clock
functions

Network Connector

Control Connections

The terminals are clearly identified by a label on the
microcontroller backplate. In the case of manual trans­fer switches, or in other applications not requiring the
microprocessor, clearly marked terminal blocks are
provided in the upper left corner of the control panel
for the engine start control wires.

Figure 6

DANGER

HAZARDOUS VOLTAGE

(Can Cause Severe Injury or Death)

Turn OFF all power before installation, adjustment, or removal of transfer switch or any of its components.

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

Entelli-Switch 250 Controller

Entelli-Switch 250 Controller

Consists of two major assemblies:

I. The Microprocessor contains the following:

A. Entelli-Switch 250 Board - Customer Input

and Output (I/O) for system interface. Located
on the left hand side of the back of the unit
(see figure 7)

1. I/O accessories that can be found here are:
a. Engine start relay P output
b. Pre-Signal to transfer T3, W3 and

UMD output (optional)

c. Transfer Inhibit Q3 and Q7 input

(optional)
d. Remote test Q2 input (optional)
e. Network interface ZNET

input/output (optional)

B. LCD and Keypad located on the exterior

of the door (see figure 8)

1. User accessibility to the following:
a. LED indication of source

availability

b. LED indication of transfer

switch position

c. LCD screen indicates:

(1) timer count down (numeric)
(2) event reporting (text)

d. Keypad provides user interface to:

[in conjunction with LCD screen]

(1) Setting sensors and timers
(2) Configuring logic accessories

II. The Controls Power Supply (CPS)

Contains transformers which drop line voltage
to control level for controller input and SCR
inputs (see figure 7).

Figure 7

Figure 8

I/O Interface

CPS

Engine Start Relay P

Battery Strip

and

Access

Code Label

Entelli-Switch 250

Board

S1 OK

21:56

MON 23 APR 2002

MORE TEST

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

Entelli-Switch 250 Controller (cont’d)

Figure 9

LCD & Keypad

These options are accessible through the LCD and
keypad (see figure below). To become familiar with the
options loaded into a particular unit, scrolling through
the SET and CFG menu will show the descriptions of
the options (see pages 16-17). These menus are the very
same menus that are used to access the setting and/or
configuration of these options. The SET (setting) menu
is primarily used to show or change, time and voltage
settings. The CFG menu is primarily used to turn an
option on or off. When scrolling through these menus,
no changes can be made without entry of the access code.

The factory set six-digit access code is located on a white
label on the back of the unit (see figure 11 pgs. 16-18).

The Entelli-Switch 250 has many logic options. Each
controller is downloaded with options at the time of
manufacture. The collection of options that any one
controller has is specified at the time of order placement.
The following pages include all the options that can
reside in the controller. Not all units include all options.

Source 1 LED (Green)
indicates Source 1 is
acceptable for use

Source 1 Position LED (Green)
indicates Power Panel (ATS)
is closed to Source 1 position

Source 2 Position
LED (Red) indicates
Power Panel (ATS)
is closed to
Source 2 position

Source 2 (Red)
indicates Source 2
is acceptable for use

LCD Screen

Current Time,
Day and
Date of Display

Menus (MORE, CFG, TEST)

#1 or the word
on the LCD above the key.
The word above the key
changes depending on which
screen is being displayed.

S1 OK

* E *

01: 50

FRI 31 MAY 2003

MORE CFG TEST SET

Entelli-Switch 250

#2 or the word
on the LCD above the key.
The word above the key
changes depending on which
screen is being displayed.

Exercise Event
"Impending"

SET Menu

Keypad

#4 or the word
on the LCD above the key.
The word above the key
changes depending on which
screen is being displayed.

#3 or the word
on the LCD above the key.
The word above the key
changes depending on which
screen is being displayed.

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

User Setting for Voltage & Frequency

Standard 3-Phase Sensing
on 3 and 4 Pole Units

Source 1

Under Voltage "Restore"

Factory Default: 90%
This adjustment determines the minimum acceptable
voltage required to transfer to Source 1.
Adjust via the SET menu. Range is 85% to 100% in
1% increments (see page 17).
Once satisfied, the T timer will begin timing
to transfer to Source 1.

Under Voltage "Fail"

Factory Default: 80%
This adjustment determines the low voltage threshold.
Adjust via the SET menu. Range is 75% to 98% in 1%
increments (see page 17).
"Fail" must be a minimum of 2 % below "Restore"
setting. Once voltage falls below threshold, P timer
begins timing to signal Source 2 Generator to start.

Under Frequency "Restore"

Factory Default: 95%
This adjustment determines the minimum acceptable
frequency required to transfer to Source 1.
Adjust via the SET menu. Range is 90% to 100% in
1% increments (see page 17).
Once satisfied, the T timer will begin timing
to transfer to Source 1.

Under Frequency "Fail"

Factory Default: 90%, (5 seconds minimum).
This adjustment determines the low frequency threshold.
Adjust via the SET menu. Range is 88% to 98% in 1%
increments (see page 17).
"Fail" must be a minimum of 2 % below "Restore"
setting. Once satisfied, the T timer will begin timing to
transfer to Source 1.

Over Frequency "Restore"

Factory Default: 102%
This adjustment determines the minimum acceptable
Over Frequency threshold at which the transfer switch
is allowed to re-transfer to Source 1.
Adjust via the SET menu. Range is 102% to 104% in
1% increments (see page 17). “Restore” must be a
minimum of 1% below “Fail” setting.

Over Frequency "Fail"

Factory Default: 105%
This adjustment determines the maximum acceptable
Over Frequency.
Adjust via the SET menu. Range is 103% to 105% in 1%
increments (see page 17).Once exceeded, the P timer
begins timing to signal the generator to start.

Source 2

Under Voltage "Restore"

Factory Default: 90%
This adjustment determines the minimum acceptable
voltage required to transfer to Source 2.
Adjust via the SET menu. Range is 85% to 100% in
1% increments (see page 17).
Once satisfied, the W timer will begin timing
to transfer to Source 2.

Under Voltage "Fail"

Factory Default: 80%
This adjustment determines the low voltage threshold.
Adjust via the SET menu. Range is 75% to 98% in 1%
increments (see page 17).
"Fail" must be a minimum of 2 % below "Restore"
setting. Once voltage falls below threshold, T timer
will be bypassed to expedite the transfer to Source 1.

Over Voltage "Fail"

Factory Default: 110%
This adjustment determines the maximum acceptable
Over Voltage. Adjust via the SET menu. Range is 105%
to 110% in 1% increments (see page 17). Once exceed­ed, the T timer will be bypassed to expedite the transfer
to Source 1.

Over Voltage "Restore"

Factory Default: 105%
This adjustment determines the minimum acceptable
Over Voltage threshold at which the transfer switch is
allowed to transfer to Source 2. Adjust via the SET
menu. Range is 103% to 105% in 1% increments
(see page 17). “Restore” must be a minimum of
2% below “Fail” setting.

Under Frequency "Restore"

Factory Default: 95%
This adjustment determines the minimum acceptable
frequency required to transfer to Source 2.
Adjust via the SET menu. Range is 90% to 100% in
1% increments (see page 17).
Once satisfied, the W timer will begin timing
to transfer to Source 2.

Under Frequency "Fail"

Factory Default: 90%, (5 seconds minimum).
This adjustment determines the low frequency threshold.
Adjust via the SET menu. Range is 88% to 98% in
1% increments (see page 17).
"Fail" must be a minimum of 2 % below "Restore" setting.
Once satisfied, the W timer will begin timing to transfer
to Source 2.

Over Frequency "Fail"

Factory Default: 105%
This adjustment determines the maximum acceptable
Over Frequency. Adjust via the SET menu. Range is
103% to 105% in 1% increments (see page 17). Once
exceeded, the T timer will be bypassed to expedite the
transfer to Source 1.

Over Frequency "Restore"

Factory Default: 102%
This adjustment determines the minimum acceptable
Over Frequency threshold at which the transfer switch
is allowed to re-transfer to Source 2. Adjust via the SET
menu. Range is 102% to 104% in 1% increments
(see page 17). “Restore” must be a minimum of
1% below “Fail” setting.

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ZTSCT / ZBTSCT Operation and Maintenance Manual (71R-5000A)

Accessory Group Packages

Standard Accessory included in the group package.
Optional Accessory not included but can be added to group package.
Optional Accessory. Can not be used with accessory having the same symbol.
N/A
Denotes an Accessory with 2 circuits as a standard.
Denotes an Accessory with 3 circuits as a standard.

Table 3

**

Optional for 40-400 Amp

Accessories

6P
A1
A1E
A3
A4
Calibrate
CDT
CDP
DS**
DT
DW
E
EL/P
K/P
L1
L2
L3
L4
LN
P1
Q2
Q3
Q7
R1-3
R15D
R16
R50
S5P
S12P
S13P
T
T3/W3
U
UMD
VI
W
YEN

STDS EXES

2
2

2

2

2

2

Group Packages

CONS

2
2

2

2

SENS SPES PSGS

2
2

2

2

2
2

2

2

3
3

2

2

2

2

3