1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the GEYA GRT8-M1 Multifunction Time Relay. The GRT8-M1 is a versatile 16A time relay offering 10 distinct function choices and a wide AC/DC12V-240V voltage range, designed for various industrial and home automation applications. Please read this manual thoroughly before use to ensure safe and correct operation.
Figure 1: GEYA GRT8-M1 Multifunction Time Relay
2. Safety Instructions
- Installation and maintenance should only be performed by qualified personnel.
- Ensure the power supply is disconnected before any installation, wiring, or maintenance work.
- Verify that the voltage and current ratings of the relay match your application requirements.
- Do not expose the device to moisture, extreme temperatures, or corrosive environments.
- Always follow local electrical codes and regulations.
3. Product Overview and Components
The GRT8-M1 is an ultra-small, 18mm wide device designed for 35mm DIN rail mounting. It features three rotary switches for setting time range, time percentage, and function mode, along with LED indicators for power (green) and relay status (red).
Figure 2: Product Overview with Inputs, Outputs, and Controls
3.1. Terminals
- A1, A2: Power supply input terminals.
- S: Control input signal terminal.
- 15: Common terminal for output contact.
- 16: Normally Closed (NC) output contact.
- 18: Normally Open (NO) output contact.
3.2. Indicators
- Green LED (Un): Indicates power supply status.
- Red LED (R): Indicates relay output status.
3.3. Rotary Knobs
- Top Knob: Time range selection (e.g., 0.1s-1s, 1s-10s, 1m-10m, 1h-10h, 1d-10d).
- Middle Knob: Time percentage setting (0-100%).
- Bottom Knob: Function mode selection (A-J).
4. Setup
4.1. Mounting
The GRT8-M1 is designed for 35mm DIN rail mounting. To mount, simply clip it onto the DIN rail. To remove, pull out the red mounting clip at the bottom and detach it from the rail. The device can also be screwed through the two mounting holes for fixed installation.
Video 1: Unboxing and Physical Overview of GRT8-M1. This video demonstrates how to unbox the relay, identifies its main components, and shows the mounting clip mechanism.
4.2. Wiring
Connect the power supply to terminals A1 and A2. The control signal (if used by the selected function mode) connects to terminal S. The output load is connected to the common terminal 15 and either 16 (Normally Closed) or 18 (Normally Open) depending on the desired operation.
Figure 3: Example Wiring Diagram for E Mode (Off Delay with S Break)
Figure 4: Comparison of Wiring Diagrams for GRT8-M1 (1 SPDT output) and GRT8-M2 (2 SPDT outputs)
5. Operating Instructions
5.1. Setting Time and Function
The GRT8-M1 features three rotary knobs for precise control:
- Time Range (Top Knob): Select the desired time scale (e.g., 1s, 10s, 1m, 10m, 1h, 10h, 1d, 10d).
- Time Percentage (Middle Knob): Fine-tune the delay time within the selected range (0-100%). For example, if the time range is set to '10s' and the percentage is set to '30%', the actual delay time will be 3 seconds.
- Function Mode (Bottom Knob): Choose one of the 10 available operating modes (A-J).
Figure 5: Setting Time Range and Percentage using Rotary Knobs
Figure 6: Overview of the 10 Delay Modes (A-J)
Video 2: This video demonstrates the E-mode function, provides guidance on wiring, and explains how to set the time on the GRT8-M1 relay.
Video 3: A comprehensive demonstration of all 10 function modes (A-J) of the GRT8-M1 multifunction time relay.
5.2. Function Mode Descriptions
The GRT8-M1 offers 10 distinct function modes, categorized by their trigger mechanism:
Functions Controlled by Power Supply Voltage:
- A: On Delay (Power On): The load connects after a set delay time once power is applied.
- B: Interval (Power On): The load connects immediately upon power-on and disconnects after a set delay time.
- C: Repeat Cycle (Starting Off): The load remains off for a set time, then turns on for the same set time, repeating the cycle.
- D: Repeat Cycle (Starting On): The load turns on for a set time, then turns off for the same set time, repeating the cycle.
- J: Pulse Generator: Generates a short pulse (0.5s) after a set delay time upon power-on.
Functions Controlled by Control Input (S Terminal):
- E: Off Delay (S Break): The load is connected when the control signal (S) is applied. When the signal is removed, the load remains on for a set delay time before turning off.
- F: Single Shot: The load connects immediately when the control signal (S) is applied and disconnects after a set delay time, regardless of how long the signal is held.
- G: Single Shot Trailing Edge (Non-Retriggerable): The load connects when the control signal (S) is released and disconnects after a set delay time. Subsequent signal changes during the delay do not retrigger the timer.
- H: On/Off Delay: The load connects after a set delay time when the control signal (S) is applied. When the signal is removed, the load remains on for another set delay time before turning off.
- I: Latching Relay: The load toggles its state (on/off) with each momentary application of the control signal (S). No delay function is involved in this mode.
6. Technical Specifications
| Parameter | Value (GRT8-M1) |
|---|---|
| Function | A, B, C, D, E, F, G, H, I, J |
| Supply Terminals | A1-A2 |
| Voltage Range | AC/DC 12-240V (50-60Hz) |
| Burden | AC 0.09-3VA / DC 0.05-1.7W |
| Power Input | AC max. 6VA / 1.3W |
| Supply Voltage Tolerance | -15%; +10% |
| Supply Indication | Green LED |
| Time Ranges | 0.1s-10 days, ON, OFF |
| Time Setting | Potentiometer |
| Time Deviation | 10%-mechanical setting |
| Repeat Accuracy | 0.2%-set value stability |
| Temperature Coefficient | 0.05%/°C, at 20°C (0.05°F, at 68°F) |
| Output | 1×SPDT |
| Current Rating | 1×16A (AC1) |
| Switching Voltage | 250VAC / 24VDC |
| Min. Breaking Capacity DC | 500mW |
| Output Indication | Red LED |
| Mechanical Life | 1×107 |
| Electrical Life (AC1) | 1×105 |
| Reset Time | max. 200ms |
| Operating Temperature | -20°C to +55°C (-4°F to 131°F) |
| Storage Temperature | -35°C to +75°C (-22°F to 158°F) |
| Mounting/DIN Rail | DIN rail EN/IEC 60715 |
| Protection Degree | IP40 for front panel / IP20 terminals |
| Overvoltage Category | III. |
| Pollution Degree | 2 |
| Max. Cable Size (mm²) | Solid wire max. 1×2.5 or 2×1.5, with sleeve max. 1×2.5 (AWG 12) |
| Dimensions | 90×18×64mm |
| Standards | EN 61812-1, IEC60947-5-1 |
7. Maintenance
The GEYA GRT8-M1 time relay is designed for long-term, reliable operation with minimal maintenance. Regular inspection of wiring connections for tightness and signs of wear is recommended. Keep the device free from dust and debris. Do not attempt to open or repair the unit yourself; contact qualified service personnel if a malfunction occurs.
8. Troubleshooting
- No Power (Green LED Off): Check power supply connections to A1 and A2. Verify input voltage is within the specified range.
- Relay Not Activating: Ensure the correct function mode is selected. Check time settings (range and percentage). Verify control signal (S) if applicable for the chosen mode. Inspect load connections (15, 16, 18).
- Incorrect Timing: Recheck the time range and time percentage knob settings. Ensure they are securely set to the desired values.
- Intermittent Operation: Check all wiring for loose connections. Ensure the operating environment is within specified temperature limits.
9. Warranty and Support
GEYA products are manufactured to high-quality standards and are covered by a standard manufacturer's warranty. For warranty claims, technical support, or service inquiries, please refer to the contact information provided with your purchase or visit the official GEYA website. Keep your purchase receipt as proof of purchase.
