XBX-6021,XBX-6021AA,XBX-6021BB,XBX-6021CC頻率信號輸入隔離變送器(一入一出、一入二出、二入二出) XBX-6021,XBX-6021AA,XBX-6021BB,XBX-6021CC, XBX-6022,XBX-6022AA,XBX-6022BB,XBX-6022CC, XBX-6023,XBX-6023AA,XBX-6023BB,XBX-6023CC,