429 MHz RS-232/RS-485 Wireless Modem
The RFU-400 is an RS-232/RS-485 to 429 MHz radio modem that can be used to convert data from an RS-232/RS-485 device to an RF message that can then be transmitted in transparent mode via the 429 MHz ISM frequency band. The RFU-400 provides a maximum line of sight (LOS) transmission distance of 1000 meters (1 km) at an RF Baud Rate of 9600 bps. In order to overcome the interference that may be encountered in harsh environments, the RFU-400 allows the RF transmission Baud Rate to be configured to a minimum of 650 bps, enhancing the capability of the modem to resist noise and other interference. Additionally, the RF channels and Group IDs are adjustable, which is helpful when attempting to avoid interference encountered when two RFU-400 networks are adjacent. The 16 RF channels and 8 Group IDs can be configured in order to distinguish and control the different RFU-400 networks. The majority of these configuration parameters can be adjusted using a combination of the Rotary and DIP switches, thereby providing a simple method of maintaining the system if the RFU-400 modem needs to be replaced.

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    • 429/433 MHz Radio Frequency
    • 16 RF Channels
    • 4 RF Baud Rates
    • Includes a PA switch that can be used to enhance the RF power
    • Wireless line of sight (LOS) transmission range of up to 1000 meters at an RF Baud Rate of 9600 bps
    • Transparent transmission mode
    • Provides Baud Rates from 1200 to 115200 bps for both the RS-232 and RS-485 interfaces
    • ESD Protection: Contact +/-4 kV
    • Isolation: 3000 VDC for DC-to-DC, 2500 Vrms using a photocoupler
    • DIN-Rail Mountable
    • Operating Temperatures, -25 °C ~ +75 °C

    Hardware Specifications

    Models RFU-400 RFU-433
    RF Interface
    Radio Frequency 429.1750 ~ 429.9250 MHz
    433.1000 ~ 434.6000 MHz
    433.1000 ~ 434.6000 MHz
    Baud Rate 115200 bps ~ 650 bps 57600 bps ~ 650 bps
    Transmission Power Max 19 dBm Default 10 dBm, Max 19 dBm
    Antenna 0 dBi Omni directional
    Transmission Distance (LoS) 1000 m (at 9600 bps RF Rate and 19 dBm Tx Power) 500 m (at 9600 bps RF Rate and 10 dBm Tx Power)
    Group ID 0 ~ 7
    Protocols Transparent transmit
    Temporary Buffer Size 512 Bytes
    Configuration Rotary and DIP switch
    Repeater Mode Support 1 hop
    COM Port Interface
    RS-232 TxD, RxD and GND
    RS-485 D+, D- ; 3000 VDC for DC-to-DC
    Baud Rate (bps) 1200 ~ 115200
    Data Format N81, E81, O81
    LED Indicators
    RF_Tx Green
    RF_Rx Yellow
    PWR Red
    Intra-module Isolation 2500 Vrms for photocoupler (RS-485/RS-232 side)
    EMS Protection
    ESD +/- 4 kV Contact
    EFT +/- 1 kV
    Surge +/- 1 kV
    Input Voltage Range +10 VDC ~ +30 VDC
    Power Consumption 1 W (Max.)
    Flammability Fire Retardant Materials
    Dimensions (W x L x H) 108 mm x 84 mm x 33 mm ( not include antenna )
    Antenna Dimensions (L x Ø) 108 mm x 10 mm
    Installation DIN-Rail
    Operating Temperature -25 °C ~ +75 °C
    Storage Temperature -30 °C ~ +80 °C
    Relative Humidity 10 ~ 90% RH, Non-condensing

    Ordering Informations

    RFU-400 CR  RS-232/RS-485 to 429 MHz Radio Modem (RoHS)
    RFU-433 CR RS-232/RS-485 to 433 MHz Radio Modem (RoHS)








    rfu-433_ru400_datasheet v1.00