KNX-GW-MODBUS-RSxxx Application : KNX bus coupling for counters with Modbus/RTU interface The bus coupler represents a bus master of the Modbus/RTU interface. A connection can be realized via ( a ) RS485 (maximum 32 subscribers incl. Master) or ( b ) RS232 (P2P). This selection must be observed when ordering and can not be switched by application. There are 32 M-Bus data points available, which can be assigned freely to the different devices. Product Data Base: KNX_GW_ModBus.knxprod The M-Bus Gateway is set up using the ETS ( KNX Tool Software ) with the associated application program. All functions are parameterized and programmed by ETS. Number of ModBus devices ( RS232 ) 1 Cable length see RS232 specification Number of ModBus devices ( RS485 ) max. 31 member Cable length see RS485 specification Number of consumption data points 32 can be assigned freely Auxiliary voltage for ModBus devices 12VDC / max. 100mA Operating voltage KNX KNX Busvoltage 21 .. 32VDC Power consumption KNX approx. 240 mW ( at 24VDC ) Auxiliary voltage 24 .. 32VDC Power consumption auxiliary voltage Depending on the number of ModBus devices to be supplied max. 100mA Bus coupler integrated Environment temperature Storage: -20 .. +85 °C Operation: -20 .. +55 °C Housing plastic Housing dimension ( 50 x 50 x 20 ) mm ( W x H x D ) 58mm diagonal Protection class IP20 Article number (a) 40310007 (b) 40300007