Differential temperature controller N321S The N321S is a controller intended for solar water heating applications. It controls the water circulation system based on the difference of temperature between the solar collector and the storage tank (or swimming pool). The instrument contains two NTC-type temperature sensors and a control output for activating the water circulation pump. It provides protections against overheating and freezing to the piping, preventing damages to the system.
- Sensor input: Pt100 (-50 to 300ºC), Pt1000 (-200 to 530°C), or thermistor (-50 to 120ºC)
- IP65 enclosure frontal protection
- Display indication does not change during defrost cycles
- Minimum ON and OFF durations accessed by the user
- Relay SPDT: 1 HP 250 Vac / 1/3 HP 125 Vac (16 A Resisitive) (up to 1HP compressors)
- Resolution: 0.1°C from -19.9 to 199.9°C
- Accuracy: ± 0.5°C/°F ±1 digit
- Adjustable hysteresis
- Sampling: 1.5 per second
- Working temperature: 0 to 50°C
- Power supply: 85-250Vac (internal) or 12-24Vac/dc
- Digital communication via RS485 with Modbus RTU protocol (optional)
- Dimensions: 75x33x75mm