Eltako 2078003
Eltako R12-100-230V Switching Relay User Manual
Model: 2078003
1. Introduction
This manual provides essential information for the safe and effective installation, operation, and maintenance of the Eltako R12-100-230V Switching Relay. Please read this manual thoroughly before proceeding with any installation or operation.
2. Safety Information
WARNING: Risk of electric shock. Disconnect power before installation or servicing.
- Installation and servicing must be performed by qualified personnel only.
- Observe all local and national electrical codes and regulations.
- Do not exceed the specified maximum voltage and current ratings of the device.
- Ensure proper grounding where required.
- Do not operate the device if it appears damaged.
3. Product Overview
The Eltako R12-100-230V is a compact switching relay designed for DIN rail mounting. It features a single normally open (NO) contact and supports manual operation with a switching position indicator.

Image: Front view of the Eltako R12-100-230V Switching Relay, showing terminals A1, A2, 1, and 2, along with the 16A 250V rating and 230V AC coil voltage. The manual operation lever and switching position indicator are also visible.
Key Features:
- Row installation device (DIN rail mountable)
- 1 x Normally Open (NO) contact
- Rated for 16 A / 250 V switching current
- 230V AC coil voltage
- Equipped with manual operation capability
- Includes a clear switching position indicator
4. Setup
Installation Requirements:
- Standard DIN rail (35mm) for mounting.
- Appropriate wiring for 230V AC power supply and load connections.
- Basic electrical tools (screwdriver, wire strippers).
Installation Steps:
- Disconnect Power: Ensure all power to the installation area is disconnected at the main circuit breaker before beginning.
- Mount the Relay: Snap the Eltako R12-100-230V relay onto the DIN rail in the desired position.
- Connect Coil Power: Connect the 230V AC control voltage to terminals A1 and A2. A1 is typically the phase (L) and A2 is the neutral (N).
- Connect Load: Connect the circuit to be switched to terminals 1 and 2. Terminal 1 is the input for the load circuit, and terminal 2 is the output. Ensure the load current does not exceed 16A.
- Verify Connections: Double-check all wiring connections for tightness and correctness according to the wiring diagram.
- Restore Power: Once all connections are secure and verified, restore power to the circuit.
5. Operating Instructions
The Eltako R12-100-230V relay operates by applying voltage to its coil (terminals A1 and A2). When 230V AC is applied, the internal contact (between terminals 1 and 2) closes, allowing current to flow through the connected load.
Manual Operation: The relay is equipped with a manual operation lever. This lever allows for manual switching of the contact independent of the coil voltage. Push the lever to change the contact state. The switching position indicator will show the current state of the contact.
Switching Position Indicator: A visual indicator on the front of the relay shows the current state of the contact (open or closed).
6. Maintenance
The Eltako R12-100-230V Switching Relay is designed for long-term, maintenance-free operation under normal conditions. No routine maintenance is required.
- Periodically inspect the terminals for secure connections.
- Ensure the operating environment is free from excessive dust, moisture, and corrosive substances.
- Clean the exterior with a dry, soft cloth if necessary. Do not use liquid cleaners.
7. Troubleshooting
If the relay is not functioning as expected, refer to the following table for common issues and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Relay does not switch when coil voltage is applied. | No power to coil (A1/A2). Incorrect coil voltage. Faulty wiring. Internal relay failure. | Check power supply to A1/A2. Ensure coil voltage is 230V AC. Verify all wiring connections. Replace the relay if internal failure is suspected. |
| Load does not receive power when relay is switched. | No power to load input (terminal 1). Load circuit open. Overload condition. Faulty wiring. Internal contact failure. | Check power supply to terminal 1. Inspect the load circuit for breaks. Ensure load current does not exceed 16A. Verify all wiring connections. Replace the relay if internal contact failure is suspected. |
| Manual operation lever does not move or is stuck. | Mechanical obstruction. Internal mechanical failure. | Check for any foreign objects. If stuck, the relay may need replacement. |
8. Specifications
| Parameter | Value |
|---|---|
| Model Number | 2078003 |
| Rated Coil Voltage | 230V AC |
| Max. Switching Current | 16 A |
| Max. Switching Voltage | 250 V |
| Contact Type | 1 Normally Open (NO) Contact |
| Mounting Type | DIN Rail (Screw mounting) |
| Operation Mode | Manual |
| Product Dimensions (L x W x H) | 9 x 6 x 2 cm |
| Product Weight | 90 g |
| Connector Type | Quick coupling |
9. Warranty and Support
For information regarding product warranty, technical support, or service, please contact your authorized Eltako distributor or visit the official Eltako website. Please have your product model number (2078003) and purchase details available when seeking support.
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