1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the LCWLYOBM GRT8-A1 Single Function Time Relay. This device is designed for industrial control applications requiring precise power-on delay functionality. Please read this manual thoroughly before installation and operation to ensure correct usage and optimal performance.
Safety Warning:
- Ensure all power is disconnected before installation or maintenance.
- Installation should only be performed by qualified personnel.
- Adhere to all local electrical codes and regulations.
2. Product Overview
The GRT8-A1 is a single-function time relay that provides a power-on delay. When power is applied, the relay waits for a set duration before activating its output contacts. This function is crucial for sequencing operations, protecting equipment, or managing power distribution in various industrial and automation systems.
Image 2.1: Front view of the GRT8-A1 Single Function Time Relay, showing terminals A1, S, A2, and output contacts 15, 16, 18, along with the time adjustment knobs.
The GRT8 series includes different models for various timing functions:
- GRT8-A (A1, A2): Power-on delay function. The relay energizes after a set time once power is applied.
- GRT8-B (B1, B2): Delayed disconnection function. The relay immediately energizes upon power application and de-energizes after a set time.
Image 2.2: Illustration comparing the functionality of A-type (power-on delay) and B-type (delayed disconnection) relays within the GRT8 series. The A-type activates after a delay, while the B-type deactivates after a delay.
3. Specifications
| Specification | Value |
|---|---|
| Model | GRT8-A1 |
| Function | Single Function Time Relay (Power-on delay) |
| Rated Voltage Range | AC/DC 12-240V |
| Output Contacts | 1 x SPDT (Single Pole Double Throw) |
| Rated Current | 16A (AC-1) |
| Mounting | DIN Rail |
| Package Dimensions | 1.18 x 0.79 x 0.39 inches |
| Item Weight | 1.76 ounces |
| Manufacturer | LCWLYOBM |
4. Setup and Installation
4.1 Mounting
The GRT8-A1 time relay is designed for DIN rail mounting. Securely clip the relay onto a standard 35mm DIN rail in an appropriate electrical enclosure.
4.2 Wiring Diagram
Refer to the wiring diagram below for proper connection. Ensure all connections are tight and secure to prevent electrical hazards and ensure reliable operation.
Image 4.1: Wiring diagram for the GRT8-A1 time relay. L and N represent the live and neutral power inputs. A1 and A2 are the control voltage terminals. S is the external control input. 15 is the common contact, 16 is normally closed (NC), and 18 is normally open (NO).
Terminal Descriptions:
- A1, A2: Power supply terminals for the relay (AC/DC 12-240V).
- S: External control input (if applicable for specific models or functions).
- 15: Common contact for the output relay.
- 16: Normally Closed (NC) contact. Connected to 15 when the relay is de-energized.
- 18: Normally Open (NO) contact. Connected to 15 when the relay is energized (after delay).
5. Operating Instructions
The GRT8-A1 features two rotary knobs for precise time adjustment. These knobs allow you to set both the time range and a percentage of that range.
Image 5.1: Knob time adjustment chart for the GRT8-A1. Knob 1 selects the time range (e.g., 1s, 10s, 1m, 10m, 1h, 10h, 1d). Knob 2 adjusts the percentage (10% to 100%) within the selected time range.
Setting the Time Delay:
- Knob 1 (Time Range): Rotate the upper knob to select the desired time range (e.g., 1 second, 10 seconds, 1 minute, 10 minutes, 1 hour, 10 hours, 1 day).
- Knob 2 (Percentage): Rotate the lower knob to select the desired percentage of the chosen time range (from 10% to 100%).
Example: To set a 5-minute delay:
- Set Knob 1 to '10m' (10 minutes).
- Set Knob 2 to '50%' (50% of 10 minutes is 5 minutes).
Operation Sequence (Power-on Delay - GRT8-A1):
- Apply power to terminals A1 and A2. The green 'Un' LED will illuminate, indicating power is present.
- The timing period begins. During this time, the output contacts (15-18) remain open.
- After the set time delay has elapsed, the output relay energizes. The red 'R' LED will illuminate, and contacts 15-18 will close (15-16 will open).
- The relay remains energized as long as power is supplied to A1-A2.
- To reset the timer, disconnect power from A1-A2.
6. Maintenance
The GRT8-A1 time relay is designed for long-term, maintenance-free operation under normal conditions. However, periodic checks are recommended:
- Visual Inspection: Periodically inspect the relay for any signs of physical damage, discoloration, or loose connections.
- Cleaning: If necessary, gently clean the exterior of the relay with a dry, soft cloth. Do not use solvents or abrasive cleaners.
- Connection Integrity: Ensure all wiring connections remain tight and free from corrosion.
Caution: Do not attempt to open or repair the relay. Refer to qualified service personnel for any issues beyond basic maintenance.
7. Troubleshooting
If the GRT8-A1 time relay does not function as expected, consider the following:
| Problem | Possible Cause | Solution |
|---|---|---|
| Relay does not energize after delay | No power to A1/A2; Incorrect wiring; Faulty unit | Check power supply; Verify wiring against diagram; Replace unit if faulty |
| Green 'Un' LED not illuminated | No power to A1/A2 | Check power supply and connections |
| Red 'R' LED not illuminating | Timing not complete; Faulty unit | Wait for set delay; Replace unit if faulty |
| Incorrect timing | Knobs set incorrectly | Re-adjust time range and percentage knobs |
8. Warranty and Support
For warranty information or technical support regarding your LCWLYOBM GRT8-A1 Single Function Time Relay, please contact your point of purchase or the manufacturer directly. Ensure you have your product model number and purchase details available when seeking support.
Manufacturer: LCWLYOBM