Fully HART compliant for communication with any HART instrument and error-free slave testing. DC-DC isolation power draws from USB port and needs no external power supply. Three modes: 1) 24VDC/270Omega. 2) Normal. 3) 270Omega. The mode is easily slide-switch selected so yoursquoll always have a power supply or loop resistor with you. Easy installation and use, this modem can power all 2-wire HART devices-independent of supplier. Rugged aluminium alloy case gives you industrial-grade reliability in a small package. Free HART application software for you to configure your HART device.Smart Design, smaller than a normal name card.operating system: 98/2000 / XP / 7/8/10 Brief Instruction The WS232UP USB-HART Modem provides a complete and flexible PC communication link to HART networks and power kit and loop resistor, for commissioning, servicing, calibrating, or acquiring data from any HART instrument or transmitter. The WS232UP is developed based on BELL202 modem standard, this external interface is rugged and compact and ideal choice for field service, commissioning, engineering, training, table top shows, lunch and learns and demo cases.