HESC-T-029 is a repeater with photoelectric isolation and complies with RS-485 standard. It can extend the communication distance of RS-485 BUS network, and increase the quantity of RS-485 network devices. The built-in DC/DC isolated module can provide as high as 2,500 Vrms isolated voltage. The fast instant voltage restraint on both sides is designed to protect RS-485 interface. It adopts advanced TVS (TRANSIENT VOLTAGE SUPPRESSOR). Normally, TVS tube is in high impedance state. When both sides of TVS tube suffer from high power impact in a sudden, the voltage restraint will fast lower the impedance from both sides, and absorb in big current. Therefore, the voltage on both sides are fixed at pre-determined value and protects the component of circuit from damage. This voltage restraint provides 600W for each wire with lightning and ESD protection, and the protection to surge voltage and instant over-voltage on circuit which is caused by various reasons. The tiny inter-electrode capacitance ensures high speed transmission for RS-485 ports. RS-485 adopts 2-pin terminal block as input and output.

This repeater has built-in zero delay auto receiving and transmitting conversion and unique I/O circuit auto control data flow direction without any handshake signal (RTS, DTR). Jumper wire setting is not required for realizing half-duplex (RS-485) mode. Each repeater is allowed to connect 128 RS-485 devices with baud rate 300 bps - 115.2 Kbps.