references
Compact air-air rooftop units
PJ range
Running the unit in free-cooling mode allows it to make best use of outdoor air conditions when these are more favourable than the return air conditions. This allows the cooling capacity to be reduced. The percentage of outdoor air can vary between 0% and 100%. There are three options for free-cooling management: • Thermal, by comparing the temperatures. • Enthalpic, by comparing the enthalpies. • Thermoenthalpic, by comparing the enthalpies and correcting for temperature. This is the optimum solution as it takes the variability of the climate into account.
Thermal free-cooling
Specific humidity
By default, the electronic control is supplied with a graphic terminal installed on the electrical cabinet of the unit, but these other configurations also are available:
Graphic terminal
User terminal
• User terminal installed on the electrical cabinet, instead of the graphic terminal. • User terminal installed on the electrical cabinet and graphic terminal remote up to 50 meters. • User terminal installed on the electrical cabinet and graphic terminal remote up to 200 meters (two TCONN bypass cards must be added). • Graphic terminal installed on the electrical cabinet and graphic terminal remote up to 200 meters (two TCONN bypass cards must be added).
Dry temperature
200 m
Enthalpic free-cooling
Specific humidity
0,8 m
S90CONN002
RJ12
TCONN
TCONN
Graphic terminal
μPC MEDIUM
Dry temperature
ic halp oent g m Ther -coolin free
Thermoenthalpic free-cooling
Specific humidity
• Control without terminal (for units with shared terminal in a pLAN network). By default, the electronic control is configured for a standalone unit, but it is also possible to place it in a pLAN network (μPC MEDIUM Local Area Network) as Master or Slave. This control allows the connection to a centralised technical management system by using a specific BMS card for some of the following communication protocols: • RS485 serial cards for network communication with protocols: Carel, Modbus, LonWorks®, BACnetTM MSTP, Konnex. • Ethernet pCO Web card for network communication with protocols: Modbus TCP/IP, BACnetTM Ethernet, TCP/IP, SNMP V1-2-3, FTP and HTTP.
y energ more es It sav
Dry temperature
Outdoor air humidity sensor (compulsory in units with optional enthalpic or thermoenthalpic free-cooling) There are 2 options: • Sensor supplied with the unit. • Sensor installed on another unit of the local network (pLAN).
RS485 Carel/Modbus card Ethernet pCO Web card
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HEAT PUMPS - AIR CONDITIONNING - REFRIGERATION - AIR HANDLING - HEAT EXCHANGE - NA 17.01 A