The device is a standard signal isolator with a 24V DC power output. It works on high-linearity analog optocoupler principle. The device converts 4-20mA dc current into 4-20mA dc current or 0-5v(or 1－5V) dc voltage with single output or double outputs. Meanwhile, it supplies an isolated 24V DC power to the input section. The input, outputs and power supply are electrically isolated from each other. The unit features in their high accuracy, high isolation, low drift and wide range of operation temperature. They can well avoid the common-mode noise and power line interference generated during the transmission of signals from transducers or instruments. It is especially suitable to use in these devices, which requires electrically isolated, such as transducers and meters. It may be widely used in measuring and controlling systems with PLC, Computer and automatic control systems.