# General information
Download technical specification[Technical Specification](https://www.atreyo.in/sites/default/files/a-download/AMB-8I-4O%20Technical%20Specification.pdf)
The AMB-8I-4O input/output expander with Modbus RTU and IEC-60870-5-101 protocol support. (under development). It has 8 isolated digital inputs with voltage range up to 30VDC and 4 relay output with 5A 230V range and NO contacts. The power supply range is 8 to 48V DC. The use of DC / DC technology for supplying relays enables a wide range of supply voltages. ---