TWO-WIRE TRANSMITTER WITH ISOLATED OUTPUT CAN Russian patent published in 2008 - IPC G08C19/02 

FIELD: measuring equipment.

SUBSTANCE: transmitter of adjustable parameter (100), preferably including output circuit (400, 300) providing bidirectional communication lines HART and local network of controllers (LOOP+, LOOP-, CAN, GROUND). Output circuit of transmitter includes connection contacts of sensor circuits (202). Isolated circuit (201) is connected to connection contacts of sensor circuit. Isolated circuit includes sensor circuit measuring process variable. Isolated circuit further contains galvanic barrier insulant (204) providing galvanic isolation of sensor electric circuit from bidirectional communication lines HART and local network of controllers. Multilevel power supply (Fig. 9A-9B) controls power. Other objects can include diagnostic output (934) current limiter terminators of controller local network, time sequence of microcontroller switching on and off, local operator interface and power supply control.

EFFECT: improved quality and noise immunity of transmission.

27 cl, 15 dwg