ComPacT™ NSX100-250 MicroLogic™ 4.2 Trip Units

Safety Warnings

⚠️ DANGER: Failure to follow these instructions can result in death or serious injury.

• Hazard of Electric Shock, Explosion or Arc Flash: Apply appropriate personal protective equipment (PPE) and follow safe electrical work practices (NFPA 70E, CSA Z462, NOM-029-STPS or local equivalent). This equipment must only be installed and serviced by qualified electrical personnel. Turn off all power supplying this equipment before working on or inside. Always use a properly rated voltage sensing device to confirm power is off. Put back all devices, doors, and covers before turning on power. Beware of potential hazards and inspect the work area for tools and objects.
• Voltage Limit for Installation: Do not install a MicroLogic 4.2 trip unit on a network with a voltage above 440 V~.
• Hazard of Fire: When installing the MicroLogic trip unit, ensure snap-off screws (A) break when tightened. Use snap-off screws LV429513 for installation. If replacing a trip unit with a different rating, redefine settings and adapt connection characteristics.
• Hazard of Equipment Damage: Be careful not to pinch wires when installing the front cover. Tighten all front cover screws to the stated torque. Do not overtorque screws. Do not use power equipment to torque screws.
• Absence of Earth-Leakage Protection: MicroLogic 4.2AL trip units do not protect against earth-leakage faults; they only indicate their presence.

California Proposition 65 Warning: This product can expose you to chemicals including lead and lead compounds, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

Product Overview

The ComPacT™ NSX100-250 series offers advanced protection and control for electrical distribution systems. The MicroLogic™ 4.2 and 4.2AL trip units provide sophisticated electronic trip functions, including:

• Overload protection (Ir)
• Short-circuit protection (Io, Isd)
• Earth-leakage protection (IΔn)
• Adjustable time delays (Δt)

These units are designed for reliable operation in various industrial and commercial environments.

Installation Instructions

1. Required for Installation

Ensure you have the following items:

• ComPacT NSX100-250 circuit breaker
• MicroLogic 4.2 or 4.2AL trip unit
• Snap-off screws LV429513 (x12)
• Tools: PZ2 screwdriver, 3.5 mm (1/8 in.) screwdriver, T10 screwdriver, T25 screwdriver.
• Accessories: LV429451, GHD16303AA (refer to specific documentation if required).

2. Before Working on Equipment

1. Turn off all power supplying this equipment before working on or inside it.
2. Use the push-to-trip button to trip the device.
3. Use a properly rated voltage sensing device to confirm power is off.

3. Installing the Trip Unit

Follow these steps:

1. Loosen and remove screws from the front cover or accessories as indicated in the instruction sheet shipped with the device.
2. Install the trip unit into its designated compartment.
3. Ensure the trip unit is correctly seated. The unit should click into place.
4. Secure the trip unit using the provided snap-off screws (LV429513), tightening them with a T25 screwdriver to 0.9 N.m (8 lb-in). The screws are designed to break off once the correct torque is applied.
5. Attach any necessary accessories.

4. Reinstalling Front Cover

Before energizing the device, put back the front cover or accessories to prevent access to live terminals. Ensure all screws are tightened to the specified torque and that wires are not pinched.

Trip Unit Adjustment

The MicroLogic trip units allow for precise adjustment of protection parameters. The IΔn dial must be in the OFF position when not actively testing or using earth-leakage protection.

Key Adjustment Parameters:

• In (Rated Current): Set according to the circuit breaker rating (e.g., 40/100A, 64/160A, 100/250A).
• Io (Instantaneous Short-Circuit Threshold): Typically set as a multiple of In.
• Ir (Long-Time Delay Current): Adjustable from 0.4 to 1 times the rated current (In). Example: For In=63A, Ir can be set from 0.4*63A to 1*63A.
• Isd (Short-Time Delay Current): Adjustable as a multiple of Ir. Example: Isd = 5 x Ir.
• Δt (Time Delays): Adjustable time settings for short-circuit protection (e.g., 50ms, 100ms, 200ms, 500ms, 1000ms).

Refer to the specific settings diagrams for detailed adjustment ranges and examples.

Testing Procedures

1. Dielectric Test

This test verifies the insulation integrity of the trip unit. The dial must be in position B while the circuit breaker is in use. For the dielectric test, turn the dial to position A (Test). Do not close the transparent cover during the test. After the test, return the dial to its original position B.

2. Earth-Leakage Protection Test

Press the test button to simulate an earth-leakage fault and test the differential protection function. This test is mandatory before commissioning.

Periodic Testing Recommendations:

• In the absence of local regulations, Schneider Electric recommends testing:
  • (1) every 3 months
  • (2) once a month for devices in corrosive or harsh environments.

Wiring and Diagrams

The MicroLogic 4.2 and 4.2AL trip units feature detailed internal schematics and connection points for various functions, including auxiliary contacts (SDx Module) for remote signaling.

MicroLogic 4.2 Wiring Example:

• The main circuit is protected by the trip unit.
• The SDx Module provides signaling outputs (SD1, SD3, SD4) for status indication (e.g., trip, alarm).
• Connections are made via terminals for power supply and signaling.

MicroLogic 4.2AL Wiring Example:

• Similar to MicroLogic 4.2, with specific considerations for the 4.2AL model.
• The diagram illustrates the sequence for testing and the connection of the SDx Module.
• Ensure connections are made according to the terminal markings and the provided diagrams.

Sealing and Manufacturing Date

Sealing Accessory

To install the sealing accessory, consult the instruction sheet GHD16296AA.

Manufacturing Date Code

The product's manufacture date is coded as PP-YYYY-Www-D, where:

• PP: Plant code
• YYYY: Year of manufacture
• Www: Week of manufacture
• D: Weekday of manufacture (Monday = 1)

Example: 7Q-2019-W20-3 indicates a product manufactured at plant 7Q on Wednesday, May 15, 2019.

Contact Information

Schneider Electric Industries SAS
35, rue Joseph Monier
CS 30323
F - 92506 Rueil Malmaison Cedex
www.se.com

Schneider Electric Limited
Stafford Park 5
Telford, TF3 3BL
United Kingdom
www.se.com/uk

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