SiUS181305E Branch Provider (BP) Unit ControlFunction 586.2 Branch Provider (BP) Unit Electronic Expansion ValveControlThis function provides instructions regarding the absolute flow rate, relative flow rate and fullyclosing from the outdoor unit to the BP unit in order to ensure outdoor unit compressor safety andoptimum refrigerating cycle of the system.With the transmission a permit/prohibit flag for each distribution control in the BP unit, thedistribution control startup timing is controlled by the outdoor unit.6.2.1 Electronic Expansion Valve Initial Opening SettingOutline This function improves stability of the system to set initial opening of the electronic expansion valveat starting operation.When the EV opening command from outdoor unit is lifted, the following opening setting isperformed.Detail Tr: room thermistor temperatureTa: outdoor temperatureTarget opening = 350 pulse6.2.2 Electronic Expansion Valve Flow Rate RestrictionOutline This function prevents deviation from the specified electronic expansion valve range by restrictingthe electronic expansion valve flow rates of the operating and non-operating indoor units duringcompressor operation. It also prevents the generation of abnormal noise such as refrigerant flowingsound by restricting the circulation of refrigerant according to the operating conditions (unit ON/OFF) of indoor units.Detail Restriction of electronic expansion valve opening degrees of operating indoor units;... Restriction of maximum and minimum flow rates based on constantRestriction of electronic expansion valve opening degrees of non-heating indoor units;... Restriction of minimum flow rate based on constant... Maximum flow rate determined based on flow rates of operating indoor unitsA B07 ~ 12 class 140 Ta Tr 015 ~ 18 class 156 Tr Ta 2.524 class 170522518286559Target opening (pulse) = × (Tr (˚C) – 14) + A – B × (Ta (˚C) – Tr (˚C))= × (Tr (˚F) – ) + A – B × × (Ta (˚F) – Tr (˚F))
