Telecom Shelter Air Circulation System

The EC-Fan48V is an ideal addition to telecom shelter configurations to help reduce air conditioner load and in-turn lower energy costs, to help removal of hydrogen gas build-up, and to provide fresh air circulation if air conditioners are not functioning.

The fan system provides continuous monitoring of inside and outside air temperature and humidity as well as hydrogen sensor output. The fan system also has independent controls and monitoring for the intake and exhaust fans, maximizing efficiency of the unit. The EC-Fan48V has continuous monitoring of fans. It reports blocked or non-operational fans, hydrogen sensor status and system status via alarm relays.

The EC-Fan48V circulates fresh air into and inside air out of a telecom shelter when the following trigger conditions occur:

  • Inside air temperature exceeds the set temperature level. The turn on temperature is set to 80F by default and can be changed to a custom temperature.
  • When enthalpy cooling is selected and temperature outside the telecom shelter is cooler than temperature inside. Free air cooling is provided when user defined enthalpy settings are met. The fan system will also detect inside shelter dew point temperature and automatically shut off before moisture builds.
  • When hydrogen gas levels are detected above the set threshold. The fan will exhaust the flammable hydrogen gas from the shelter automatically.

Fan Components:

  • Fan Intake Assembly – brings fresh air into the telecom shelter. The intake assembly monitors inside temperature and humidity level, hydrogen sensor contacts, presence of fire alarm contacts. Two alarm relays are provided as follows
    • One set of form C alarm contacts (C, NO, NC), contact rating (1A, 48V) to indicate hydrogen sensor contacts.
    • One set of form C alarm contacts (C, NO, NC), contact rating (1A, 48V) to indicate the system alarm condition.
  • Fan Exhaust Assembly – exhausts the inside air.
  • Outside Sensor Unity – monitors outside air temperature and humidity level.


Fan Specs:

  • Intake assembly dimensions – 15.5″ x 12.5″ x 4″
  • Exhaust assembly dimensions – 12.5″ x 12.5″ x 2.5″
  • Outdoor sensor unit dimensions – 7.5″ x 7.5″ x 4.5″
  • Intake and exhaust fans are rated at 300 CFM. Higher CFM fans are available for greater air flow demand. When enthalpy cooling is selected, intake fan speed is changed to allow for mixing of cooler outside air and warmer inside air. Using PWM scheme, controller lowers intake fan speed when outside air temperature is much cooler than the inside air temperature. Free air cooling is provided when user defined enthalpy settings are met.
  • Maximum rating for EC-Fan48V system is 48V at 8A. The input power lines should be protected with a 10A circuit breaker.
  • An optional 400V, 60A DC relay may be mounted on the intake assembly plate to control heaters/loads. Controller provides drive signal. Load/heater power must be protected by a separate 75A circuit breaker.