Serial communications allows for a much greater bandwidth and more information transfer capability than traditional 4 – 20 mA signaling. Ontrac produces a wide range of serial communication options through the use of an optional communications board. These can be used with both Multitrac and Easytrac actuators.
Ontrac offers Profibus DP (Decentralised Peripherals) up to a baud rate of 1.5Mbit/s. Our actuators are supplied with active bus termination. The electrical connections are via RS485 type A.
Ontrac offers Modbus RTU protocol communications at a baud rate up to 38.4kbits/s. Our factory default speed is 9.6kbits/s giving a 1.5km maximum distance between nodes. We use a master / slave query response polling cycle with CRC (Cyclic Redundancy Check).
Ontrac can provide HART Communication Protocol (Highway Addressable Remote Transducer) connectivity. HART allows use of conventional 4 – 20 mA wiring