Innovative technologies for safe handling of electrical power to achieve high availability

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  • Electrical safety for unearthed power supplies (IT systems)
  • Insulation monitoring equipment, insulation fault location systems
  • Power supplies for medical applications
  • Measuring and monitoring relays
  • Electrical safety for earthed power supplies (TN systems)
  • Using renewable energies efficiently: wind power, photovoltaics
  • Test systems for electrical equipment and medical technology


The signal converter SMI473 converts digital signals (operating and alarm messages) to serial output signals for the BMS bus. Its 12 digital inputs for potential-free contacts can be split into two groups as alarm or operating messages. Factory setting: 8 inputs for alarm messages and 4 inputs for operating messages.


  • 12 digital inputs
  • Indicator LED for each channel
  • LEDs: Power On, ALARM, activities on the RS-485 interface
  • RS-485 interface (BMS bus)
  • Operating principle selectable: N/O or N/C operation
  • Factory setting: 8 inputs for alarm messages and 4 inputs for operating messages


  • Converts digital signals to serial output signals for the BMS bus

Downloads for SMI473-12

CE Declarations of conformity SMI47x 76.6 KB 12.08.2022 06:17:26
Manuals SMI473 722.1 KB DE13.05.2019 10:31:42D00360
Manuals SMI473 722.1 KB EN13.05.2019 10:31:42D00360
Datasheets SMI473 282.0 KB DE07.09.2020 06:28:54D00360
Datasheets SMI423 276.9 KB EN07.09.2020 07:59:52D00360

SMI473-12 Variants

TypeSupply voltage UsArt. No.
SMI473-12DC 77…286 V/AC 85…265 V, 50…60 HzB92047023
SMI473-1221DC 12,5…80 VB92047024