... function:1. Through the USB output of meter, it can truly display the synchronous value of display meter on PC conveniently.2. It can ... any problems.(Note: The max number of digital meters can be connected is 127.) voltage meter - power supply AC220V ,DC5V,DC12V, ... use high accuracy* Many years of export experience and 12 years experience cooperation with Panasonic voltage meter with RS232, RS485 can ...