Control Resources is an OEM (Original Equipment Manufacturer) supplier of fan and motor speed control and alarm products to the telecommunications, electronics, and HVAC industries. Our products are not intended for end-user/aftermarket applications.
CRI recommends using induction motors, either Permanent Split Capacitor (PSC) or Shade Pole type. Other motor types are generally not controllable.
TRIAC Controllers
Nimbus II and Nimbus regulate motor speed by varying the voltage to the motor. Confirm TRIAC controllability with the fan/motor manufacturer before installation or contact CRI customer service for testing recommendations. Attempting to control a fan that is not compatible could cause excessive heating and could permanently damage the fan motor.
Variable Frequency Drives (VFD)
Stratus II regulates motor speed by varying the frequency and voltage to the motor. An LC filter should be connected to the output of the drive for motors that are not inverter duty grade.
Electrical Noise Emissions and Filtering
Electrical noise emissions (EMI) are highly dependent on load and environment. SmartFan Nimbus and Stratus can meet EN55011/FCC Class A emissions standards in many applications. For applications requiring additional filtering, CRI recommends the following filters or equivalents:
| EN55011/FCC Class A: 150 kHz – 30 mHz | EN55011/FCC Class B: 10 kHz – 30 mHz |
| Astrodyne TDI: RP225-3-.47-QD | Astrodyne TDI: RP225-3-10-QD |
| Corcom S series | Corcom Q series |
Note: Using multiple controllers in a facility (hotel, school, office building) can cause line interference. For these installations, class B filtering is recommended.