The N322S is a controller originally intended for solar water heating applications, harnessing renewable energy by controlling liquid or air circulation based on the temperature difference between two supplied NTC sensors (included). Unlike the N321S, the N322S adds a second relay output — a booster/alarm relay that monitors sensor 2 independently and can be used for low or high temperature alarm signalling.
In a solar application, the control output activates the water circulation pump to maintain an even temperature between the solar collector and storage tank — useful for swimming pools, hot tubs, and hot water recycling systems. For air destratification/circulation, the control output activates a high-level fan to keep an even temperature throughout a building's layers, eliminating heat wasted at the top of warehouses, factories, or agricultural buildings. It's also used to cool grain stores and maintain the correct differential. As part of a solar system it also provides protection against overheating and freezing to the piping, preventing damage to the system.
The N322S is also available as a 12-24V model or with optional RS485 communications.
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Novus N322-S Datasheet Download
Technical Details
NTC Thermistor, 10kΩ @ 25°C; range: -30 to +105°C (-22 to 221°F). Accuracy: 0.6°C (1.1°F)
Sensor interchangeability: 0.75°C (1.35°F) — compensated by the offset parameter in the controller
Measurement Resolution: 0.1°C from -19.9°C to 119.9°C, 1°C elsewhere
Output 1: Relay SPDT; 1 HP 250 Vac / 1/3 HP 125 Vac (16 A Resistive). Output 2: Relay 3A / 250 Vac, SPST
Power Supply: 100 to 240 Vac/dc ±10%. Optionally: 12 to 30 Vdc/ac. Mains Frequency: 50~60 Hz. Power Consumption: 5 VA
Dimensions: 75 x 34 x 75 mm. Weight: 100g. Panel: 70 x 29mm
Environment: Operating 0 to 40°C (32 to 122°F). Storage -20 to 60°C (-4 to 140°F). Relative humidity 20-85% non-condensing
Case: Polycarbonate UL94-2. Protection: Front panel IP65, Box IP42. Suitable wiring: up to 4.0mm²
Frequently Asked Questions
What's the difference between this and the N321S?
The N322S adds a second relay output — an independent booster/alarm relay monitoring sensor 2, usable for low or high temperature alarm signalling on top of the standard differential control function.
Do I need to buy sensors separately?
No — the N322S is supplied complete with 2 NTC temperature sensors ready for solar collector/tank or dual-point differential use.
Is there a 24V or RS485 version?
Yes, see our N322S (12-24V). Optional RS485 communication models are also available.
Industry Applications
- Solar Water Heating — maintains even temperature between collector and storage tank, protecting against overheat and freeze.
- Alarm-Monitored Systems — independent booster/alarm relay flags low or high temperature conditions.
- Building Air Destratification — activates high-level fans to redistribute trapped heat in warehouses and agricultural buildings.