MicroLogic Trip Unit Power Supply

Internal Power Supply for MicroLogic 5 and 6 Trip Units

The protection functions and the test functions of MicroLogic and 6 trip units operate with the current through the internal current transformers (CT).

When the load current is higher than 20% of the rated current In, the internal current supply provides the power supply for the full functioning of the MicroLogic trip unit. This includes:

• The MicroLogic display screen and LEDs

• The maintenance and diagnostic functions

To provide a power supply to the MicroLogic 5 or 6 trip unit when the load is below 20% of the rated current In, and maintain the full functioning of the MicroLogic trip unit, one of the following optional power supplies can be used:

• An external 24 Vdc power supply connected permanently to the MicroLogic trip unit

• A power supply connected temporarily to the test port on the MicroLogic trip unit:

  • Pocket battery

  • Service Interface connected to a power supply

  • USB maintenance interface connected to a power supply or a PC

Internal Power Supply for MicroLogic 7 Trip Units with Integrated Earth-Leakage Protection

The protection functions and the test functions of MicroLogic Vigi 7 trip units operate with the current through the internal current transformers (CT) and the internal voltage power supply.

When the load current is lower than 20% of the rated current In, the internal voltage power supply provides the power supply for the following minimum functions of the MicroLogic trip unit:

• The protection functions

• The indication LEDs

• The earth-leakage protection test

When the load current is higher than 20% of the rated current In, the internal current supply provides the power supply for the full functioning of the MicroLogic trip unit. In addition to the minimum functions, this includes the following functions:

• The MicroLogic display screen and indication LEDs

• The maintenance and diagnostic functions

To maintain the full functioning of the MicroLogic 7 trip unit when the load is lower than 20% of the rated current In, one of the following optional power supplies can be used:

• An external 24 Vdc power supply connected permanently to the MicroLogic trip unit

• A power supply connected temporarily to the test port on the MicroLogic trip unit:

  • Pocket battery

  • Service Interface connected to a power supply

  • USB maintenance interface connected to a power supply or a PC

External 24 Vdc Power Supply

The 24 Vdc power supply maintains the operation of the functions of the MicroLogic trip unit in all circumstances, including in low load conditions (load below 20%), and when the circuit breaker is open and not energized.

The 24 Vdc power supply is essential to enable the MicroLogic trip unit to display the trip cause.

The external 24 Vdc power supply is provided to the MicroLogic trip unit once it is connected to another module in the ULP system (for example, IFM Modbus-SL interface for one circuit breaker).

When the MicroLogic trip unit is not connected to a ULP module, it can be connected directly to an external 24 Vdc power supply by using the optional 24 Vdc supply terminal block.

One 24 Vdc power supply can be used to provide power to several MicroLogic trip units or other ULP modules.

Recommended 24 Vdc Power Supplies

Available 24 Vdc power supplies include the range of Phaseo ABL8 power supplies and the AD power supplies. For more information, refer to LVPED217032EN ComPact NSX & NSXm Catalogue.

Characteristic	Phaseo ABL8 power supply	AD power supply
Illustration
Overvoltage category defined by IEC 60947-1	Category II	Category IV per IEC 62477-1 (Vac model) Category III per IEC 62477-1 (Vdc model) Category III per UL 61010-1
Input supply voltage AC	110–120 Vac 200–500 Vac	110–130 Vac 200–240 Vac
Input supply voltage DC	–	24–30 Vdc 48–60 Vdc 100–125 Vdc
Dielectric withstand	Input/output: 4 kV RMS for 1 minute Input/ground: 3 kV RMS for 1 minute Output/ground: 0.5 kV RMS for 1 minute	Input/output: 3 kV RMS for 1 minute (110–130 Vac and 200–240 Vac model) 3 kV RMS for 1 minute (110–125 Vdc model) 2 kV RMS for 1 minute (24–30 Vdc and 48–60 Vdc model)
Temperature	50 °C (122 °F) 60 °C (140 °F) with 80% nominal load maximum	70 °C (158 °F)
Output current	3 A, 5 A, or 10 A	1 A
Ripple	200 mV peak-peak	200 mV peak-peak
Output voltage setting for line loss compensation	24–28.8 Vdc	22.8–25.2 Vdc

ULP Module Consumption

The following table lists the ULP module consumption:

For more information on power supplies, refer to DOCA0093EN ULP System (IEC Standard) - User Guide

Pocket Battery

Use the pocket battery to provide a temporary power supply to the MicroLogic trip unit.

The pocket battery enables use of the MicroLogic display screen and keypad for setting and displaying when the power supply to the MicroLogic trip unit is interrupted.

The pocket battery can be connected by using the trip unit connector (supplied with the pocket battery) connected to the test port on the MicroLogic trip unit.

Check the charge level of the pocket battery by sliding the switch to the Test position. The green LED on the pocket battery lights up to indicate the battery status.

For more information on the pocket battery, refer to DOCA0140EN ComPact NSX - Circuit Breakers and Switch-Disconnectors 100–630 A - User Guide.

Service Interface

Use the Service Interface to provide a temporary power supply during periods of setting, commissioning, testing, and maintenance.

For more information on the Service Interface, refer to DOCA0170EN Service Interface - User Guide.

USB Maintenance Interface

Use the USB maintenance interface to provide a temporary power supply during periods of setting, commissioning, testing, and maintenance.

The USB maintenance interface is connected to the test port on the MicroLogic trip unit.

The USB maintenance interface must be connected to the mains power supply or to a PC

For more information on the USB maintenance interface, refer to .