lindab | we simplify construction Regula Master HTML Pascal Outdoor air cooling If the Air Handling Unit does not have a cooling battery there is risk that the AHU cannot deliver cold air in the supply ducts to the rooms in hot summer days when outdoor temperature is higher than indoor temperature. To prevent unnecessary overheating of rooms the Outdoor air cooling function can be activated. In case the outdoor temperature is higher than the room tem- perature the LRM/SRM will automaticly change the Basic cooling temperature setpoint, and thus making sure that all SRC regulates to AirflowMinOcc . This control is made once every hour ( at hour change ). If a CO 2 sensor is connected to SRC and the CO 2 level is exceeded, then the airflow can still raise to AirflowMaxOcc . The Outdoor air cooling function is performed by LRM/SRM, and a duct temperature sensor ( PT1000 in supply duct ) is connected to the LRM/SRM. However in a system with GRM and two or more LRM it is possible to connect the duct temperature sensor to the GRM instead, using only one central sensor. The central duct temperature connected to GRM is then transmitted to all LRM. When outdoor air cooling is used, all SRC connected to same LRM/SRM must have the same Basic cooling tempe- rature setpoint ( default 22°C ). ACB free cooling optimizer (Active chilled beam free cooling optimizer) This function uses the temperature before and after the AHU to choose if it´s most energy efficient to use water or air as first regulation sequence. ACB free cooling is only active when there´s no presence to avoid draft problems. All connected SRCs running program 8 will be affected when ACB free cooling is used. When using ACB free cooling two PT1000 sensors should be connected, one to main supply air (Tmain supply) and one to AHU inlet (T AHU inlet) both sensors are then connected to GRM/SRM. Forced Extract Balancing (FEB) Forced extract balancing is used if there´s extra extract that should be compensated elsewhere, e.g. kitchen hoods, fume hoods. Ultra link is installed in the extra extract to measure flow. Corresponding flow is sent to ERC (up to 16) which decrease their amount of air to keep balance in the room. The UL that should be connected to least numbers of ERC:s should have number 1. (UL1) the UL with most connected ERC:s should be the last one. Make sure to dimension and configure the system, so the connected ERCs can cover the airflow of the Forced extraction. Inspection mode Function in SRM/LRM used to change mode in all SRC at once for inspection and control measuring in a chosen time period ( default 240 min ) or without time, then it will continue until it´s deactived. The SRC´s will automatically change back to their individual original mode Inspection mode is done. The following modes can be used: V nom - Airflow 7 m/s Bypass - AirflowMax Occupied - flows between AirflowMinOcc and AirflowMax- Occ depending on actual room temperature and Basic cool- ing setpoint ( default 22°C ) + setpoint offset Unoccupied - AirflowMinOcc , as long as actual room temperature is between heating setpoint at unoccu- pied ( default 15°C ) and cooling setpointvat unoccupied ( default 30°C ). Standby - flows between AirflowStandby and AirflowMax- Occ , depending on actual room temperature and Basic cool- ing setpoint in standby mode. Off - closed damper ( leakage flow ). Override control Override is done on GRM/SRM and activated via BMS or DI3. Regula combi (supply and extract) is set to V nom , bypass, occupied, stand by or off (closed damper) simultaneously on all connected LRMs. When override mode is active it´s possible to decide what output that should be sent to AHU in percentage. All buttons on Regula combi will be blocked and an A-alarm is shown in all connected Regula masters. 4 Lindab reserves the right to make changes without prior notice 2020-07-09
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