Hubbell LX-450, LX-440 User Manual

Hubbell Industrial Controls, Inc.

A subsidiary of Hubbell Incorporated

4301 Cheyenne Drive
Archdale, NC

Instruction Manual

Transfer switches

LX-440 Non-Automatic

Telephone [phone]

FAX [phone]

LX-450 Automatic

100, 200, 260, 400, 600, 800, 1000, 1250 Ampere

2, 3, 4 Pole

Publication No. 201

April, 2001

Transfer Switch

Table of Contents

1.0 Introduction....................................................................................................................................3

2.0 Specifications and Certifications ..................................................................................................4

Specifications .....................................................................................................................................4

Certifications ......................................................................................................................................4

3.0 Installation......................................................................................................................................4

Receiving and Storage........................................................................................................................5

Location..............................................................................................................................................5

Line Connections................................................................................................................................5

4.0 Operation........................................................................................................................................5

Automatic Operation ..........................................................................................................................6

5.0 Standard and Optional Features ..................................................................................................7

Standard Features ...............................................................................................................................7

Optional Features................................................................................................................................8

6.0 Maintenance .................................................................................................................................10

Transfer Test.....................................................................................................................................10

Troubleshooting................................................................................................................................11

Settings .............................................................................................................................................11

7.0 Transfer Control Relay Board....................................................................................................12

8.0 Plant Exerciser Timer .................................................................................................................14

Set the time .......................................................................................................................................14

Programming ....................................................................................................................................14

9.0 Spare Parts and Drawing References ........................................................................................16

Spare Parts ........................................................................................................................................16

Drawing References .........................................................................................................................16

Page 2 of 16 Pages

Transfer Switch

1.0 Introduction

Hubbell’s non-automatic, LX-440, and automatic, LX-450, transfer switches are available in 2, 3, and 4
pole models with ampere ratings of 100 to 1250 A. The transfer switches are available as open type or
in an individual cabinet.

The automatic transfer switch has a Solid State Transfer Control Module, LX-301, that monitors voltage
and controls the transfer to and from the normal and emergency sources. The non-automatic transfer
switch has a selector switch to manually initiate transfer. A handle is included with all transfer switches
to manually close the normal or emergency contacts.

Emergency

Source

Normal

Source

PRM

optional

Control
Module

(LX-301)

To engine

start contacts

(If generator backup)

Normal Source
Transformer

Transfer Control

Relay Board

TSE

TSN

To load

Switching

Mechanism

Emergency Source
Transformer

Figure 1-1 Block Diagram of automatic transfer switch showing one phase

Page 3 of 16 Pages

Transfer Switch

2.0 Specifications and Certifications

Specifications

Switch Mechanism Solenoid Actuation

Short Circuit Ratings of Transfer Switches

100 A
200 A
260, 400, 600 A
800, 1000, 1250 A

Control Voltage 120 VAC

Pick-up Voltage 90% of normal source voltage

Drop-out Voltage 84% of normal source voltage

Auxiliary Contacts 10 A, 125/250 VAC

Note

Time delay settings and voltage pick-up and drop-out levels are set at the factory and should not be
changed without consulting the factory.

RMS Symmetrical Amperes

42,000
50,000 When protected by
65,000 a circuit breaker.
85,000

90% of emergency source voltage

84% of emergency source voltage

Certifications

Hubbell’s Automatic transfer switches meet the requirements for all of the certifications listed below.

UL 1008 Standard for Safety for automatic transfer
switches

NEC Article 517, Health Care facilities

NEC Article 702, Optional Standby Systems

NEC Article 701, Legally Required Standby
Systems (LX-450 only)

NFPA 20 Installation of Fire Pumps

3.0 Installation

Refer to the transfer switch nameplate to ensure that the voltage, current, and horsepower ratings are
compatible with the load.

Refer to the receiving, handling, storage, installation, and inspection procedures in the Instruction
Manual that accompanies the combination Fire Pump Controller and automatic transfer switch. Many of
the procedures in the installation section are applicable to the automatic transfer switch in the adjoining
cabinet. For automatic transfer switches sold as an individual unit, and for additional information,
follow the procedures below.

Page 4 of 16 Pages

Transfer Switch

Receiving and Storage

After receiving the transfer switch inspect the cabinet for any damage that may have occurred during
shipping. If the transfer switch is not installed immediately, cover the cabinet and store in a dry area.
Condensation can corrode the contacts and other metal parts.

Location

The transfer switch should be located as close as possible to the engine generator or to the alternate
power source. If possible, there should be a clear line of sight between the transfer switch and the
engine generator.

Line Connections

Refer to the drawings posted inside the cabinet door and in the drawing packet for customer
connections.

Before drilling and punching holes in the cabinet for wiring connections cover the transfer switch with a
protective covering. Small debris falling into the automatic transfer switch may jam the switching
mechanism or may cause electrical failure.

Ensure that the normal (primary), emergency (alternate), and load isolation switches are open before
making connections. Connect the load, normal source, and emergency source power cables in the same
phase sequence. Refer to the latest NFPA 70 and Field Connections Wiring Diagram for cable sizes and
torque requirements.

All other standard customer connections are made to PTB1 on the left side of the mounting panel. Use
approved 14-gauge wire for all control connections. Typical field connections are shown below.

Terminal Connections Description

PTB1-1 and –2 Engine Start Contact, for generator set

PTB1-5 and -6 TSNa4 contacts closed, normal position

PTB1-7 and -8 TSNa3 contacts closed, normal position

PTB1-9 and -10 TSEa4 contacts closed, emergency position

PTB1-11 and -12 TSEa3 contacts closed, emergency position

TSN - Auxiliary Contact, Normal source
TSE - Auxiliary Contact, Emergency source

After installation is complete, perform a transfer test as described in section 6.0 Maintenance.

4.0 Operation

Refer to the schematic and wiring diagrams that are provided with the transfer switch. These drawings
are provided in a packet, along with this manual. A schematic is also posted on the inside of the cabinet
door.

Page 5 of 16 Pages