Intermatic MIL72ASTUZH-24 Electromechanical Time Control User Manual

1. Product Overview

The Intermatic MIL72ASTUZH-24 is a 24-hour electromechanical timer module designed for integration within control panels. It supports both surface and DIN rail mounting configurations. This timer is suitable for light-duty commercial applications requiring 24 VAC single-phase control, such as lighting systems, HVACR equipment, pumps, motors, fan controls, access control systems, and general-purpose electrical circuits. The unit includes a pre-installed, non-replaceable Nickel Metal Hydride battery for internal functions.

This device features a synchronous drive mechanism and a 21 Amp SPDT switch. It is equipped with captive trippers that allow for 15-minute interval programming. Electrical connections are made via 1/4-inch quick-connect terminals. A 3-way override function provides manual control flexibility.

2. Safety Information

WARNING: Risk of electric shock. Installation and servicing of this device should be performed by qualified personnel only. Disconnect power at the circuit breaker or fuse box before installing or servicing. Follow all local and national electrical codes.

• Ensure the power supply matches the timer's voltage rating (24 VAC).
• Do not exceed the maximum load rating of 21 Amps.
• Keep the device dry and away from moisture.
• Do not attempt to open or repair the unit. There are no user-serviceable parts inside.

3. Package Contents

• 1 x Intermatic MIL72ASTUZH-24 Electromechanical Time Control Module

4. Product Features

• Synchronous drive mechanism (timekeeping relies on continuous power).
• 21 Amp Single-Pole Double-Throw (SPDT) switch for versatile load control.
• Captive trippers for setting ON/OFF intervals in 15-minute increments.
• 1/4-inch quick-connect terminals for secure and efficient wiring.
• 3-way manual override switch for temporary control without altering the program.
• Designed for surface or DIN rail mounting within control panels.
• Includes a non-replaceable internal Nickel Metal Hydride battery for internal functions.

5. Installation

Important: Installation must be performed by a qualified electrician in accordance with all applicable electrical codes.

1. Disconnect Power: Before beginning installation, ensure that power to the circuit is completely disconnected at the main service panel (circuit breaker or fuse box).
2. Mounting:
   • Surface Mount: Secure the timer module to a flat surface inside the control panel using appropriate fasteners through the designated mounting holes.
   • DIN Rail Mount: Attach the timer module to a standard DIN rail within the control panel.
3. Wiring: Connect the 24 VAC power supply and the load wires to the 1/4-inch quick-connect terminals as per the wiring diagram provided with the product packaging. Ensure all connections are secure.
4. Verify Connections: Double-check all wiring for correctness and security before restoring power.
5. Restore Power: Once installation is complete and verified, restore power to the circuit.

Figure 1: Front view of the Intermatic MIL72ASTUZH-24 timer module, showing the 24-hour dial with captive trippers and the manual override switch.

6. Operation

The MIL72ASTUZH-24 operates on a 24-hour cycle, allowing for precise scheduling of connected devices. As a synchronous drive timer, it relies on continuous power for timekeeping. In the event of a power outage, the timer will stop and will not automatically resume at the correct time when power is restored.

1. Set Current Time: Rotate the outer dial clockwise until the current time aligns with the time indicator arrow (usually a small triangle or line on the stationary part of the timer). The dial is marked with AM/PM indicators. If a power outage occurs, you will need to reset the current time.
2. Program ON/OFF Times:
   • The dial has captive trippers around its circumference. Each tripper represents a 15-minute interval.
   • To set an "ON" period, push the trippers outwards for the desired duration.
   • To set an "OFF" period, leave the trippers in their inward position.
   • The timer will activate the connected device when the dial rotates to an "ON" (outward) tripper and deactivate it when it rotates to an "OFF" (inward) tripper.

7. Manual Override

The timer features a 3-way manual override switch, typically located on the front of the unit. This switch allows for temporary control of the connected load without affecting the programmed schedule.

• AUTO: The timer operates according to the programmed schedule.
• ON: The connected device is continuously ON, overriding the schedule.
• OFF: The connected device is continuously OFF, overriding the schedule.

Return the switch to the "AUTO" position for the timer to resume its programmed operation.

8. Maintenance

The Intermatic MIL72ASTUZH-24 is designed for minimal maintenance. No routine user maintenance is required.

• Cleaning: If necessary, gently wipe the exterior of the timer with a dry, soft cloth. Do not use liquid cleaners or solvents.
• Battery: The unit contains a non-replaceable Nickel Metal Hydride battery for internal functions. This battery is not user-serviceable.

9. Troubleshooting

If troubleshooting steps do not resolve the issue, contact Intermatic customer support for further assistance.

10. Specifications

11. Warranty and Support

For warranty information, technical support, or service inquiries, please contact Intermatic customer service. Refer to the official Intermatic website or the product packaging for the most current contact details and warranty terms.

Intermatic Website: www.intermatic.com