How It Works
The device connects to three electrodes — an Upper Electrode, a Low Electrode, and a Well Bottom (Base) Electrode — placed at different heights inside the tank or well.
- While the water level sits between the low electrode and the bottom electrode, the relay remains de-energized (not activated).
- When the water level rises and touches the upper electrode, the relay activates.
- As the water level falls back below the low electrode, the relay deactivates again.
Relay contact behavior:
- When activated: contacts 1 (16-NC) and 2 (15-COM) open; contacts 2 (15-COM) and 3 (18-NO) close.
- When deactivated: contacts 1 (16-NC) and 2 (15-COM) close; contacts 2 (15-COM) and 3 (18-NO) open.
Two-electrode operation: If only two electrodes are needed, use the Upper (U) and Lower (L) electrode terminals only, and leave the Base (B) electrode unused.
Sensitivity Setting
Sensitivity is adjustable via the onboard sensitivity dial (up to 100KΩ):
- Make sure the electrodes are in contact with the water while adjusting.
- Turn the dial toward 100KΩ.
- The relay activates once the device detects the electrodes.
- For reliable detection, the liquid’s resistance must be lower than the sensitivity value that has been set.
Technical Specifications
| Parameter | Value |
|---|---|
| Operating Voltage (Un) | 150 – 260V AC |
| Operating Frequency | 50/60 Hz |
| Operating Power | < 6 VA |
| Operating Temperature | -20°C to +55°C |
| Operating Altitude | < 2000 m |
| Sensitivity | < 100 KΩ |
| Contact Rating | 5A / 250V AC (Resistive Load) |
| Protection Class | IP20 |
| Connection Type | Terminal connection |
| Cable Diameter | 2.5 mm² (SSR-05) / 1.5 mm² (VSR-05) |
| Weight | < 250 g |
| Display | 2 x LED |
| Mounting | Vertically panel-mounted or DIN-rail mounted |
Dimensions
CST-05: 84.5 mm x 80 mm x 44 mm (with 7.62 mm and 75 mm reference spacings; 35.5 mm depth)
CSR-05: 23.15 mm x 5.08 mm mounting pitch, 90 mm x 94.6 mm panel dimensions (34.5 mm / 49.25 mm / 57.75 mm / 65.8 mm / 45 mm reference measurements)
(See connection and dimension diagrams for exact terminal layout and mounting measurements.)
Maintenance
- Switch off the device and disconnect it from all connections before cleaning.
- Clean the housing with a dry swab only.
- Do not use any conductive material or chemical cleaner, as this may damage the device.
- After cleaning, verify that the device operates correctly before returning it to service.
Safety Warnings
- Use the device strictly according to the instruction manual.
- Do not use the device in wet or damp environments.
- Always include a switch and circuit breaker in the installation.
- Position the switch and circuit breaker close to the device, within easy reach of the operator.
- Clearly label the switch and circuit breaker as the disconnect point for this device.
- Ensure the liquid being monitored is non-flammable and non-explosive.
