FAQs related HVAC control solutions

General questions about Sentera devices

• What is indoor air quality or IAQ?

• What does ‘IP protection’ mean?

• What is PI control?

• What is a PWM signal?

• What is a potentiometer?

• What is a control switch for EC fans?

• How to connect a 0-10 Volt control signal?

• What is a Common Ground?

• What is the difference between VDC and VAC?

Modbus RTU – how to interconnect Sentera devices

• How to adjust parameters of a Sentera device?

• What is Modbus RTU communication?

• What is PoM or Power over Modbus?

• What cable to use for a Modbus network?

• What is the maximum cable length for a Modbus RTU network?

• What is the maximum current in a PoM network?

• Can a Sentera device with Modbus RTU communication work stand alone?

• How to restore the factory default settings of a Sentera device?

• Can Sentera products communicate with non-Sentera products via Modbus RTU communication?

• What is a Modbus Network Bus Terminator or NBT?

• What should I pay attention to when creating a Modbus RTU network?

• What is Baudrate in a Modbus RTU network?

Motor and fan related questions

• What is a control signal?

• What is the difference between an AC and EC motor?

• How to regulate AC fan speed?

• How to control EC fan speed?

• Kick start versus Soft start - what is the difference?

• Can I control multiple motors with one fan speed controller?

• What motor insulation class is required in combination with a fan speed controller or VFD?

• What is an electronic fan speed controller for AC motors?

• What is a transformer fan speed controller for AC motors?

• What is Ecodesign regulation EU 2019-1781?

• What does IE2 mean for VFDs?

• How to control ceiling fans with 3-speed motor?

• How many EC fans can I control with a 0-10 Volt signal?

• How do destratification fans work?

• What type of fan speed controller should I choose?

• How does an electric autotransformer work?

Sensors in an HVAC environment

• How does an NDIR CO2 Sensor Work?

• How to recalibrate a CO2 sensor?

• Why to measure temperature and relative humidity?

• What is relative humidity?

• Why measure indoor temperature?

• Why measure CO2?

• Why to measure TVOC or indoor air quality?

• Why measure CO in underground parking garages?

• What is the difference between a transmitter, intelligent sensor and sensor controller?

• Can I use a Sentera transmitter for agriculture or horticulture applications?

• What is the difference between 3-wire and 4-wire connection?

• How to measure air volume flow or air velocity?

• What is dew point temperature?

• How to interpret article codes of Sentera sensors?

• Why is mechanical ventilation important in buildings?