1. Introduction
The Intermatic ML900TW is a 900-Watt power pack designed for low-voltage lighting systems. It converts standard 120-volt AC household current to 12-volt AC, suitable for landscape lighting. This unit features an integrated timer with ground shield for automated operation and enhanced safety. It is built for durability and ease of installation, providing a reliable power source for your outdoor lighting needs.
2. Safety Information
- Always disconnect power at the circuit breaker before installing or servicing the power pack.
- This unit is designed for outdoor use and features weather-resistant housing. Ensure all connections are secure and protected from moisture.
- Do not exceed the maximum rated wattage of 900 Watts. Overloading the unit can cause damage or create a fire hazard.
- Ensure proper grounding to prevent electrical shock.
- Keep children and pets away from the unit during operation.
- Refer to local electrical codes for specific installation requirements.
3. Package Contents
Verify that all components are present before beginning installation:
- Intermatic ML900TW 900-Watt Power Pack
- Ground Shield
- 2 Sets of Trippers (for timer programming)
- Instruction Manual (this document)
4. Product Features
- 900-watt power capacity for controlling extensive lighting systems.
- Converts 120-volt AC to 12-volt AC power.
- Automatic multiple on/off timer for scheduled operation.
- Manual override switch for temporary control.
- Weather-resistant housing for outdoor durability.
- Includes three independent 300-watt circuits.
- Keyhole mountings for easy installation.
5. Setup and Installation
5.1 Mounting the Power Pack
The ML900TW features keyhole mountings on the back for secure wall mounting. Choose a suitable outdoor location that is protected from direct heavy rain and accessible for wiring and programming. Ensure the mounting surface is sturdy enough to support the unit's weight (approximately 29.8 pounds).
Image: Front view of the Intermatic ML900TW Power Pack, showing the timer dial and output terminals.
5.2 Electrical Connections
- Input Power: Connect the 120-volt AC input power supply to the designated terminals inside the power pack. Ensure the power is OFF at the circuit breaker before making any connections.
- Output Power: Connect your low-voltage landscape lighting cables to the 12-volt AC output terminals. The ML900TW includes three independent 300-watt circuits, allowing for flexible wiring of your lighting zones. Distribute the load evenly across the circuits to prevent overloading.
- Grounding: Ensure the unit is properly grounded according to local electrical codes. The included ground shield should be installed as per instructions to enhance safety.
6. Operation
6.1 Setting the Timer
The ML900TW features an automatic multiple on/off timer. Use the provided trippers to set your desired ON and OFF times. Insert the ON trippers at the times you want your lights to turn on, and the OFF trippers at the times you want them to turn off. The timer dial typically rotates over a 24-hour period.
- Rotate the timer dial clockwise to align the current time with the indicator arrow.
- Insert the 'ON' trippers into the dial at the desired activation times.
- Insert the 'OFF' trippers into the dial at the desired deactivation times.
- Ensure trippers are securely seated.
6.2 Manual Override
A manual override switch is provided to temporarily bypass the timer settings. This allows you to turn the lights ON or OFF independently of the programmed schedule. Return the switch to the 'AUTO' position for timer operation to resume.
7. Maintenance
The Intermatic ML900TW is designed for minimal maintenance. Periodically inspect the unit and wiring for any signs of damage, wear, or loose connections. Ensure the weather-resistant housing remains sealed and free from cracks. Clean the exterior with a damp cloth as needed. Do not use abrasive cleaners or solvents.
8. Troubleshooting
- Lights not turning on: Check the power supply at the circuit breaker. Verify all wiring connections are secure. Ensure the timer is set correctly and the manual override switch is not in the 'OFF' position. Check for blown bulbs in your lighting system.
- Timer not functioning: Ensure the timer dial is rotating. Check that the trippers are correctly inserted and making proper contact. If the timer mechanism appears stuck or unresponsive, the unit may require professional inspection.
- Humming noise: A slight hum is normal for transformers. However, if the hum is excessively loud or accompanied by unusual smells, immediately disconnect power and inspect for internal damage or loose components.
- Unit overheating: Ensure the total wattage of connected lights does not exceed 900 Watts. Check for short circuits in the low-voltage wiring. Ensure adequate ventilation around the power pack.
9. Specifications
| Specification | Value |
|---|---|
| Manufacturer | Intermatic |
| Part Number | ML900TW |
| Item Model Number | ML900TW |
| Item Weight | 29.8 pounds |
| Product Dimensions | 8.63 x 5 x 14 inches |
| Color | Black |
| Voltage (Input) | 120 Volts AC |
| Voltage (Output) | 12 Volts AC |
| Wattage | 900 Watts (Max) |
| Circuits | Three 300-watt circuits |
| Batteries Included | No |
| Batteries Required | No |
10. Warranty and Support
The Intermatic ML900TW Power Pack is backed by a 6-year limited warranty. For warranty claims or technical support, please contact Intermatic customer service. Keep your purchase receipt as proof of purchase.
