Introduction
The Directed Electronics Inc 528T is a versatile 12-volt accessory pulse timer designed for automotive and other low-voltage applications. It features an adjustable delay from 0 to 60 seconds and can be triggered by either a positive or negative pulse, or a state change. This manual provides essential information for proper installation, operation, and maintenance of your 528T unit.
Safety Information
- Always disconnect the vehicle's battery before beginning any electrical installation.
- Ensure all wiring connections are secure and properly insulated to prevent short circuits.
- This device operates on a 12V DC system. Do not connect to higher voltage sources.
- Installation should ideally be performed by a qualified professional or individuals with experience in automotive electrical systems.
- Protect the unit from moisture and extreme temperatures.
Product Overview
The 528T unit consists of a compact electronic module with multiple color-coded wires for various connections and an adjustable potentiometer for setting the delay time.
Image: Directed 528T Pulse Timer showing the clear casing, internal circuit board, and various colored wires extending from the unit.
Image: Top-down view of the Directed 528T Pulse Timer, highlighting the compact design and the bundle of wires.
Components
- Main Unit: Enclosed circuit board with a potentiometer for time adjustment.
- Wiring Harness: Multiple color-coded wires for power, trigger, and relay output.
- Blue Wire Loop: Used to select the trigger input type (positive or negative).
Specifications
| Feature | Detail |
|---|---|
| Input Voltage | 12V DC |
| Adjustable Timer | 0 - 60 Seconds |
| Relay Output | 30A (max) |
| Trigger Type | Positive (+) or Negative (-) Pulse, or State Change |
| Product Dimensions | 3.05 x 8 x 5 inches |
| Item Weight | 3.2 ounces |
| Model Number | 528T |
Setup and Installation
Proper installation of the 528T unit requires a basic understanding of automotive electrical systems. Refer to your vehicle's wiring diagrams as needed.
Wiring Diagram and Connections
The 528T unit features several color-coded wires. Identify each wire's function before making connections.
- Red Wire: 12V Constant Power Input. Connect this to a fused 12V constant power source.
- Black Wire: Ground Input. Connect this to a reliable chassis ground.
- Black/White Stripe Wire: Trigger Input (Negative). This wire is used for negative pulse or state change triggers.
- Yellow Wire: Trigger Input (Positive). This wire is used for positive pulse or state change triggers.
- Orange Wire: Relay Output (Normally Open - NO). This terminal connects to the device you want to power after the delay.
- Brown Wire: Relay Output (Normally Closed - NC). This terminal connects to the device you want to power until the delay activates.
- Blue Wire Loop: Trigger Selection.
Trigger Type Selection
The 528T can be configured for either positive or negative triggering using the blue wire loop.
- For Negative (Ground) Trigger: Leave the blue wire loop intact. The unit will trigger when the Black/White wire receives a negative pulse or goes to ground.
- For Positive (12V) Trigger: Cut the blue wire loop. The unit will trigger when the Yellow wire receives a positive pulse or 12V.
Connection Procedure
- Power Connections: Connect the Red wire to a fused 12V constant power source and the Black wire to a solid chassis ground.
- Trigger Connection: Based on your desired trigger type, connect either the Black/White wire (for negative trigger, blue loop intact) or the Yellow wire (for positive trigger, blue loop cut) to your trigger source. The unused trigger wire should be insulated.
- Load Connection: Connect the device you wish to control to the appropriate relay output wire.
- Use the Orange wire for a Normally Open (NO) connection. This means the circuit is open (off) until the timer activates, then it closes (on) for the set duration.
- Use the Brown wire for a Normally Closed (NC) connection. This means the circuit is closed (on) until the timer activates, then it opens (off) for the set duration.
- Insulation: Ensure all connections are properly soldered or crimped and insulated with electrical tape or heat shrink tubing.
- Mounting: Mount the 528T unit in a dry, secure location away from excessive heat or vibration.
Operating Instructions
Adjusting the Timer Delay
The 528T features an adjustable potentiometer (a small dial or screw) on the unit's circuit board. This allows you to set the delay time from approximately 0 to 60 seconds.
- Use a small screwdriver to carefully turn the potentiometer.
- Turning clockwise typically increases the delay time.
- Turning counter-clockwise typically decreases the delay time.
- Test the delay after each adjustment to ensure it meets your requirements.
Timer Activation
Once installed and configured, the timer activates upon receiving the specified trigger signal (positive or negative, depending on the blue loop setting).
- When triggered, the internal relay will switch its state (NO to closed, NC to open) for the duration set by the potentiometer.
- The timer will re-initiate if a new trigger signal is received while it is already timing, or if the trigger state changes.
Maintenance
- Regular Inspection: Periodically check all wiring connections for looseness or corrosion.
- Environmental Protection: Ensure the unit remains protected from water, dust, and extreme temperatures. If installed in an exposed area, consider adding a protective enclosure.
- Cleaning: If necessary, gently clean the exterior of the unit with a dry, soft cloth. Do not use harsh chemicals or solvents.
Troubleshooting
Unit Does Not Activate
- Check Power: Verify that the Red wire has a constant 12V supply and the Black wire has a solid ground connection.
- Check Trigger: Ensure the correct trigger wire (Black/White for negative, Yellow for positive) is connected and receiving the appropriate signal. Confirm the blue loop is correctly configured for your trigger type.
- Verify Load: Ensure the device connected to the Orange or Brown wire is functioning correctly and its wiring is secure.
Incorrect Delay Time
- Adjust Potentiometer: Carefully adjust the potentiometer on the unit. It may require fine-tuning.
- Test Repeatedly: Some units may exhibit slight variations in timing with rapid, repeated triggers. Test the delay under typical operating conditions.
Relay Not Switching
- Check Load Current: Ensure the connected load does not exceed the 30A rating of the internal relay. Overloading can damage the relay. Consider using an external relay for higher current applications.
- Internal Fault: If all other checks pass, the internal relay or circuit may be faulty.
Warranty and Support
Specific warranty information for the Directed Electronics Inc 528T is not provided in this manual. Please refer to the product packaging or contact Directed Electronics Inc directly for warranty details and technical support.
For further assistance, it is recommended to consult with an authorized Directed Electronics dealer or a qualified automotive electronics technician.
