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The N321S is a controller originally 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.

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 damage to the system.

The controller has proven to be versatile in controlling other applications such as:

Swimming Pool/Hot Tub/Hot Water

Oil Heating 

Air Circulation

Grain Cooling

The N321S is also available as a 100-240V model or with optional RS485 communications. 

- NTC Thermistor: 10 kΩ @ 25 °C, range: -30 to +105°C (-22 to 221 °F), Accuracy: 0,6 °C (1,1 ºF)

- Sensor interchangeability: 0,75 ºC (1,35 ºF)

- Measurement Resolution: 0,1º from –19.9 to 119.9º

- Output: Relay SPDT, 1 HP 250 Vac / 1/3 HP 125 Vac (16 A Resistive)

- POWER SUPPLY: 12 to 30 Vdc/ac

- Mains Frequency: 50~60 Hz

- Power Consumption: 5 VA

- Dimensions: 75 x 33 x 75 mm

- Weight: 100 g

- Panel: 70 x 29 mm