Composition Rules for IMUs

Introduction

Connection of an IMU in the ULP system is simple, but must comply with the rules concerning composition, RJ45 plug/plug ULP cords, and the ULP module power supply.

General Rule: Composition of an IMU
ToDo @Gregory: decide if rule need to be updated if an IMU with IFM/IFE + IO is possible

An IMU is composed of the following two device types:

One main device (circuit breaker or switch ) and an internal ULP communication module
One or several external ULP modules

Main device type	ULP modules
PowerPacT H-, J-, and L-frame circuit breaker with BSCM circuit breaker status control module and/or MicroLogic 5 or 6 trip unit PowerPacT H-, J-, and L-frame switch-disconnector with BSCM circuit breaker status control module	0 or 1 FDM121 display 0, 1, or 2 IO modules 0 or 1 interface among: IFE interface IFE server ⁽¹⁾ IFM interface
PowerPacT P- and R-frame circuit breaker with BCM ULP circuit breaker communication module MasterPacT NT/NW circuit breaker with BCM ULP circuit breaker communication module	0 or 1 FDM121 display 0, 1, or 2 IO modules 0 or 1 interface among: IFE interface IFE server ⁽¹⁾ IFM interface
MasterPacT MTZ drawout circuit breaker with ULP port module	0 or 1 FDM121 display 0, 1, or 2 IO modules 0 or 1 interface among: IFE interface IFE server ⁽¹⁾ EIFE embedded Ethernet interface IFM interface (LV434000 only)
MasterPacT MTZ fixed circuit breaker with ULP port module	0 or 1 FDM121 display 0, 1, or 2 IO modules 0 or 1 interface among: IFE interface IFE server ⁽¹⁾ IFM interface (LV434000 only)
(1) One IFE server with stacked IFM interfaces: In terms of power supply, the maximum number of IFM interfaces stacked to one IFE server is 11 in order to limit voltage drop. In terms of Modbus-SL communication, it depends on the performance requirement. As it takes approximately 500 ms at 19,200 Baud per device to refresh 100 registers, the more interfaces added the longer the minimum refreshment period. The minimum refreshment period depends on the number of IFM interfaces stacked to one IFE server. Multiply the time to refresh one device by the number of devices to find the minimum refreshment period expected in the application. For instance, an installation with eight IFM interfaces stacked to one IFE server at 19,200 Baud would take approximately 4 seconds to be read. For good communication performance, a maximum of eight IFM interfaces stacked to one IFE server is recommended.

These examples illustrate the composition rules for an IMU.

A	PowerPacT H-, J-, L-, P-, or R-frame, or MasterPacT NT/NW circuit breaker
B	MasterPacT MTZ circuit breaker with ULP port module
C	MasterPacT MTZ drawout circuit breaker with ULP port module and EIFE interface

General Rule: Order of ULP Modules in an IMU

Connect the ULP modules in a single IMU in any order. Base the connection on the ULP cable recommendations and the desired layout for the ULP modules in the electrical equipment.

A	A PowerPacT H-, J-, L-, P-, or R-frame, MasterPacT NT/NW, or MasterPacT MTZ circuit breaker

General Rule: ULP Line Termination

The ULP modules placed at the end of the ULP line must have a ULP line termination (part number TRV00880) on the unused ULP RJ45 connector.

Example of ULP line termination on IFE interface:

Place the ULP modules which have an internal ULP line termination at the end of the ULP line, that is:

BSCM module or MicroLogic 5 or 6 trip unit for PowerPacT H-, J-, and L-frame circuit breakers.
BCM ULP module for PowerPacT P- and R-frame or MasterPacT NT/NW circuit breakers.
ULP port module for MasterPacT MTZ circuit breakers.

NOTE: In an architecture with an EIFE interface connected to a ULP port module, the ULP port module is the end of the ULP line.

General Rule: Cables to Interconnect IMUs on Communication Networks

Do not connect the IMUs to one another with ULP cords.

Use only the Ethernet cable to interconnect IMUs connected to an Ethernet network.

A	A PowerPacT H-, J-, L-, P-, or R-frame, MasterPacT NT/NW or MasterPacT MTZ circuit breaker

Use only the Modbus cable or stacking accessory to interconnect IMUs connected to a Modbus network.

A	PowerPacT H-, J-, L-, P-, or R-frame or MasterPacT NT/NW circuit breaker

General Rule: Power Supply Through the ULP Cord

Only one device can be powered through the ULP cord. This device must be at the end of the ULP line. It can be done only for the following devices:

FDM121 display.
BSCM module and MicroLogic trip unit for PowerPacT H-, J-, and L-frame circuit breakers.
BCM ULP module for MasterPacT NT/NW and PowerPacT P- and R-frame circuit breakers.

Example: In the diagram, the FDM121 display and the PowerPacT H-, J-, and L-frame MicroLogic trip unit are powered through ULP system. The IFE server and the IO modules are connected to the power supply. As the IFM interfaces are stacked on the IFE server, they are already powered.

A	IFE server
B	IFM interfaces stacked on IFE server
C	FDM121 display
D	IO module
E	MicroLogic trip unit in PowerPacT H-, J-, and L-frame circuit breaker

NOTE: The ULP port module on MasterPacT MTZ circuit breaker must be connected to a 24 Vdc power supply.

Length of ULP Cords

The rules for ULP cord length are as follows:

The maximum length of the ULP cord between two ULP modules in an IMU is 5 m (16.4 ft) if one of the ULP modules does not have an external power supply.
The maximum length of the ULP cord between two ULP modules in an IMU is 10 m (32.8 ft) if both ULP modules have an external power supply.
The maximum length of all the ULP cords on a single IMU is 20 m (65.6 ft).
The bending radius of the ULP cords must be 50 mm (1.97 in) minimum.

Summary of Connection Rules

Characteristic	Value
Connection	Daisy-chaining of ULP cords and ULP line termination at the end of the ULP line.
Maximum length	20 m (65.6 ft) in total for the IMU. 10 m (32.8 ft) between two ULP modules if both ULP modules have an external power supply. 5 m (16.4 ft) between two ULP modules if one of the ULP modules does not have an external power supply.
Voltage range supported	24 Vdc -10%/+10% (21.6–26.4 Vdc)
Current limitation on each ULP RJ45 port	300 mA