Operational indoor air quality - Johnson Controls - LIT-12011950 - Building automation software - Smart Equipment Controller - 5.0

Smart Equipment Controls Sequence of Operation Technical Bulletin

Product name
Smart Equipment Controller
Document type
Technical Bulletin
Document number
LIT-12011950
Version
5.0
Revision date
2024-06-06
Product status
Active

Setpoints and related data

The setpoints and related data include the following items:

  • Operational indoor air quality (OprIAQ)
  • Indoor air quality source (IAQSrc)
  • Indoor air quality sensor range (IAQRange)

Inputs

The inputs include the following items:

  • Network override indoor air quality (NetIAQ) communicated value on FC Bus
  • Indoor air quality (IAQ) to IAQ terminals

Operation

Operational indoor air quality (OprIAQ) is effective only if an economizer board has been connected to the UCB following the last RELEARN SYSTEM (Relearn) operation. The operational indoor air quality (OprIAQ) and network override indoor air quality (NetIAQ) parameters are then shown in the UCB display menu.

The highest priority valid related input is used for operational indoor air quality (OprIAQ).

The operational indoor air quality (OprIAQ) has assigned priority for inputs in the following order from highest to lowest:

  • Network override indoor air quality (NetIAQ)
  • Indoor air quality (IAQ)

If the input in use becomes invalid, operational indoor air quality (OprIAQ) reverts to the next highest priority input.

The indoor air quality sensor range (IAQRange) must be set to match the ppm range of the sensor being used. This allows the control to correctly calibrate the 0-10 VDC input from the sensor to match the actual ppm measured by the sensor.

Note: Network override indoor air quality (NetIAQ) is not bound by the indoor air quality sensor range (IAQRange)

Indoor air quality source (IAQSrc) describes the input currently in use for operational indoor air quality (OprIAQ).

BAS Override
Indicates network override indoor air quality (NetIAQ)
Local Input
Indicates indoor air quality sensor (IAQ)
Unreliable
Indicates no valid related input is available and demand ventilation economizer functions that use operational indoor air quality are not permitted

Network override indoor air quality (NetIAQ) is used if a value is set or communicated within the past 15 minutes. If 15 minutes pass without a communicated value, the UI displays Value Timed Out and the next highest priority input is used.

Indoor air quality (IAQ) is used if the IAQ sensor is connected to the IAQ and COM terminals.