1. Introduction
This manual provides essential information for the safe and efficient installation, operation, and maintenance of the Eltako S91-100-12V Electromechanical Surge Switch. Please read this manual thoroughly before use and retain it for future reference.
2. Safety Information
WARNING: Electrical installation should only be performed by qualified personnel. Disconnect power before installation or maintenance to prevent electric shock.
- Ensure all local and national electrical codes are followed.
- Do not exceed the specified voltage and current ratings.
- Protect the device from moisture and extreme temperatures.
- Verify correct wiring connections before applying power.
3. Product Overview
The Eltako S91-100-12V is an electromechanical surge switch designed for installation and flush-mounted applications. It features manual operation and a switching position indicator. This device is suitable for controlling lighting circuits or other loads requiring a momentary pulse to toggle their state.

Figure 1: Front view of the Eltako S91-100-12V Surge Switch. This image shows the device with its terminals labeled A1, A2, 1, and 2, along with the manual operation button and electrical ratings (10A/250V AC, A1-A2 12V~).
4. Specifications
| Feature | Specification |
|---|---|
| Model | S91-100-12V |
| Part Number | 2613424 |
| Operation Mode | EIN-AUS (ON-OFF) |
| Current Rating | 10 Amps |
| Operating Voltage (Control) | 12 Volts AC/DC (A1-A2) |
| Switching Voltage (Load) | Up to 250V AC |
| Contact Type | 1 Normally Open (N/O) |
| Connector Type | Screw Terminals |
| Mounting Type | Surface Mount / Flush-mounted |
| Actuator Type | Push Button (Manual) |
| International Protection Rating | IP20, IP50 |
| Control Power Required | 4-5W |
| Duty Cycle | 100% |
| Dimensions (L x W x D) | 50 mm x 26 mm x 32 mm |
| Weight | 2.57 ounces (approx. 73g) |
5. Setup and Installation
Before You Begin: Ensure the main power supply to the circuit is disconnected at the breaker or fuse box.
- Mounting: The S91-100-12V can be installed in a standard electrical box for flush-mounted applications or surface-mounted using appropriate enclosures. Its compact size (50 mm long, 26 mm wide, 32 mm deep) allows for flexible placement.
- Wiring Connections: Refer to the diagram on the device for correct terminal connections.
- A1 and A2: Connect the 12V AC/DC control voltage to these terminals. A momentary pulse to these terminals will toggle the switch state.
- 1 and 2: These are the normally open (N/O) contacts for the load circuit. Connect the load (e.g., lighting) to these terminals. When the switch is activated, terminals 1 and 2 will close, allowing current to flow to the load.
- Secure Connections: Use appropriate tools to tighten screw terminals, ensuring a secure electrical connection.
- Verify Wiring: Double-check all connections against the wiring diagram to prevent short circuits or damage.
- Restore Power: Once installation is complete and verified, restore power to the circuit.

Figure 2: Detailed view of the Eltako S91-100-12V Surge Switch showing terminal labels and a simplified wiring diagram. This image clarifies the connection points for the control voltage (A1, A2) and the load circuit (1, 2).
6. Operating Instructions
The Eltako S91-100-12V Surge Switch operates by receiving a momentary 12V pulse to its control terminals (A1-A2).
- Electrical Operation: Apply a brief 12V pulse to terminals A1 and A2. The switch will toggle its state (ON to OFF, or OFF to ON).
- Manual Operation: The device includes a manual push button (indicated by 'm' or a small blue button on the front). Pressing this button will manually toggle the switch state.
- Switching Position Indicator: The device features a visual indicator (often a small window or flag) that shows the current state of the switch (ON or OFF).
7. Maintenance
The Eltako S91-100-12V Surge Switch is designed for long-term, maintenance-free operation under normal conditions.
- Cleaning: If necessary, gently wipe the exterior of the device with a dry, soft cloth. Do not use abrasive cleaners or solvents.
- Inspection: Periodically inspect wiring connections for tightness and signs of wear or damage. Ensure the device is free from dust and debris.
- No User-Serviceable Parts: Do not attempt to open or repair the device. Refer any issues to qualified service personnel.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Switch does not respond to control pulse. | No 12V control voltage; incorrect wiring of A1/A2; faulty control button/circuit. | Verify 12V supply to A1/A2. Check control circuit wiring. Test manual operation. |
| Load (e.g., light) does not turn ON/OFF. | Incorrect wiring of load terminals (1/2); faulty load; no power to load circuit. | Check wiring of terminals 1 and 2. Test the load independently. Ensure load circuit has power. |
| Switch operates intermittently. | Loose wiring connections; unstable 12V control voltage; device damage. | Tighten all screw terminals. Ensure stable 12V supply. If problem persists, replace device. |
9. Warranty and Support
Eltako products are manufactured to high-quality standards. For specific warranty information, please refer to the documentation provided with your purchase or visit the official Eltako website. For technical support or service inquiries, please contact your authorized Eltako dealer or customer service.
Manufacturer: Eltako





