Month: June 2025

Mounting

The LSM mounts in two slots of a Bulletin 1771 Series B, I/O chassis. Mounting dimensions will vary with the size of the chassis selected. 

Refer to the appropriate 1771 literature for specific dimensions.

Power Supply

The LSM backplane power requirement is 1.1A at 5V DC. Refer to the appropriate 1771 literature for additional information on available power supply current.

Chassis Grounding

For correct and reliable performance, the grounding recommendations specified for Allen–Bradley PLC systems must be followed.

Swing Arm

The LSM requires the use of a Cat. No. 1771-WC (10 position, gold contacts) Swing Arm.

Wiring

There are two sets of terminals associated with the LSM; a 10 position swingarm and an 8 position fixed terminal block. 

All customer wiring to the LSM is accomplished via these terminals on the front of the module. 

The 10–position swingarm is used to make all of the voltage (PT) connections to the module as well as the Load Share connections. 

These connections are designed to accommodate wire size 0.5 mm2 (22 AWG) through size 2.0 mm2 (14 AWG). 

The 8–position fixed terminal block is used to make all of the current (CT) connections. 

These connections are designed to accommodate gauge wire size 0.5 mm2 (22 AWG) through ring lugs size 3.25 mm2 (12 AWG). 

Phasing and polarity of the AC current and voltage inputs and their relationship are critical for the correct operation of the unit. 

Figure 2.1 through Figure 2.5 shown on Pages 2–7 through 2–11 provide wiring diagrams to help ensure correct installation. 

Two (2) conductor shielded wire (22 gauge or greater) should be used for Load Share wiring.

The shield shall be grounded at the PLC Chassis ground point only.

Location

The Bulletin 1402 Line Synchronization Module (LSM) should be installed in a Bulletin 1771 I/O chassis that is located in a dry, 

dirt free environment away from heat sources and very high electric or magnetic fields. 

The module is designed to operate in an ambient temperature between 0 and 60° Celsius. 

The LSM is typically installed in a local rack in order to maximize data transfer rates.

Enclosure

This equipment is classified as open equipment and must be installed (mounted in an enclosure during operation as a means of providing safety protection. 

The enclosure chosen should protect the LSM from atmospheric contaminants such as oil, moisture, dust, corrosive vapors, or other harmful airborne substances. 

A steel enclosure is recommended to guard against EMI (Electromagnetic Interference) & RFI (Radio Frequency Interference). 

The enclosure should be mounted in a position that allows the doors to open fully. 

This will allow easy access to the wiring of the LSM and related components so that servicing is convenient. 

When choosing the enclosure size, extra space should be allowed for associated application equipment such as, transformers,

fusing, disconnect switch, master control relay, and terminal strips.

Synchronization and Load Share Errors

In order to synchronize two three phase systems without high instantaneous

energy transfer, the voltage, frequency, and phase displacement of the two

systems must be matched. Kilowatt Load Sharing can be implemented by

matching the ratio of power system load to system capacity to the ratio of

actual alternator power to rated alternator power. The LSM provides the

following information to allow the user’s system to achieve the necessary control actions.

• Voltage Match Error (in steps of 0.05 percent)

• Frequency Match Error, or slip (in steps of 0.01 Hz)

• Synchronizing Bus to Reference Bus Phase Match Error (in steps of 1 degree)

• Load Sharing Error (scalar quantity between 0.000 and  1.000)

• Synchronization Status

— Frequency Within Limits

— Voltage Within Limits

— Phase Within Limits

— Synchronization Mode Conflict Failure

— Phase Rotation Mismatch Failure (3 phase synchronization mode only)

— No Reference Bus Voltage Present Failure

— No Synchronizing Bus Voltage Present Failure

— Reference Bus Over Voltage Failure

— Synchronizing Bus Over Voltage Failure

Measurements

In addition to the synchronization function, the LSM provides an extensive array of monitoring information 

for systems wired in Wye, Delta, or Open Delta. 

Chapter Objectives

After reading this chapter, you should be able to identify the product features and system applications.

Introduction

The Bulletin 1402, Line Synchronization Module (LSM), is designed to meet the needs of manufacturers, 

system integrators, and users of 3 phase alternators and cogeneration systems or for applications that require 

two three–phase systems to be synchronized with each other. 

The module provides means for automatic synchronization, load sharing, and high speed power system monitoring.

General Description

The Line Synchronization Module (LSM) is a two slot 1771 form factor module that fits into a standard Allen–Bradley 1771 I/O chassis. 

It performs three functions:

1. Measures appropriate parameters from the two three–phase systems and provides control and 

error signals to implement engine governor control for synchronization.

2. Provides an analog output that is representative of the ratio of the power being supplied by the alternator to the output rating of the alternator, 

reads an analog input that represents the ratio of the total system load being supplied to the total system capacity, 

and provides an error signal to adjust the alternator for proper load sharing based on the instantaneous load requirements.

3. Performs as a multi–function digital power monitor for the system.

These functions provide data and control signals which are communicated to the PLC-5 via the 1771 backplane.

Analog Servo System

The 1394 Analog Servo system (1394x-SJTxx-A) provides a digital servo drive system with a traditional ±10V DC analog interface. 

It can be used as a velocity or torque control system and is quickly commissioned with the Allen-Bradley universal Bulletin 1201 HIM

(Human Interface Module), which provides access to auto tuning and start-up prompting. 

The 1394 also provides a SCANport interface as a standard feature.

9/440 CNC System

The 9/440 CNC system module gives you all the power and programming capabilities of a 9/Series CNC,

integrated into the compact packaging of the 1394 System Module. 

The 9/440 CNC System Module provides terminating points for:

• Resolvers

• Encoder feedback (for optional position feedback or spindle control)

• Two serial ports (for communicating with the 9/Series ODS or other peripherals such as printers or tape readers)

• E-STOP string and status

• Spindle outputs

• 9/Series fiber optic ring connection

• Touch probe interface

• Remote I/O connection

GMC System

The 1394 GMC System provides all the functionality of the IMC S Class Compact Motion Controller and power conversion within the 1394 system module. 

Allen-Bradley offers two versions of the 1394 GMC system module (Standard GMC and GMC Turbo). 

Both systems are completely programmed and commissioned using GML (Graphical Motion Control

Language),offer Allen-Bradley DH485, RS-232, and RS-422 as standard communications, and ave Remote

I/O and AxisLink available as communication options.

The 1394x-SJTxx-C (Standard GMC) system supports four axis modules and provides four channels of auxiliary encoder input. 

The 1394C-SJTxx-L (Standard GMC) provides the same functionality of the 1394x-SJTxx-C, 

but supports only one axis module and provides two channels of auxiliary encoder input.

In addition, the 1394x-SJTxx-T (GMC Turbo) provides more GML application program memory and executes the programs faster. 

The 1394x-SJTxx-T offers 64K of memory with a 32-bit processor while the 1394x-SJTxx-C offers 32K of program memory with a 16-bit

processor. The 1394x-SJTxx-T also includes a direct, high speed link to the SLC 5/03, 5/04, or 5/05 that simplifies the programming required to transfer data between the 1394x-SJTxx-T and the SLC.

CNC Interface System

The 1394 9/Series CNC Interface system (1394-SJTxx-E) provides a digital servo system to be used with the 9/260 and 9/290 CNC. 

This system provides all power electronics and uses a cost-saving digital interface approach. 

Servo control for this system is handled by the 9/Series CNC. 

A fiber optic I/O ring is provided to the 1394 and the system is completely interfaced with and programmed using ODS (Off-Line Development System) and the CNC operator panel. 

The 1394 System 

The 1394 is a modular, multi-axis motion control and drive system family. 

Its unique design allows the 1394 to be used as an integrated motion controller and drive system (GMC) with Turbo or standard 

IMC S Class Compact functionality, an integrated 9/440 CNC system, 

a 9/Series CNC digital interface drive system, a SERCOS servo drive system, or an analog servo drive system.

All 1394 systems provide direct line connection (transformerless) for 360 and 480V three-phase input power, 

efficient IGBT power conversion, and slide-and-lock, module-to-module connection 

systems. Each system module can be configured with up to four axis modules, 

with each axis module interfacing to a motor. 

The 1394 provides significant panel space and interconnect savings.

SERCOS System

The 1394 SERCOS system module (1394C-SJTxx-D) provides a digital servo drive system with a fiber-optic digital network interface.

It can be used as a velocity or torque control system and is quickly commissioned with the Allen-Bradley SERCOS Interface Module

(Bulletin 1756 with 1756-MxxSE), which provides access to auto tuning and start-up prompting. 

The 1394 also provides a SCANport interface as a standard feature.

For specific installation and wiring information refer to the 1394 SERCOS Multi-Axis Motion Control System User Manual(publication 1394-5.20).