User Manual of EM760 High-Performance Inverter In the UART transmission, the data usually consists of a start bit, valid data (8 bits by default), check bit (optional), and a stop bit. The EM760 series inverter supports six data formats according to the Modbus-RTU combinations in communication. IfF10.02=0, it means that the current data consists of one start bit + eight data bits + no check bit + one stop bit. * N (NONE): no parity; E (EVEN): even parity; O (ODD), odd parity. In order to meet different needs, the inverter also supports communication timeout and response delay during the communication based on the Modbus protocol.
As shown in the figure below, the communication time interval △ tis defined as the period from the previous reception of valid data frames by the slave station (inverter) to next reception of valid data frames. If △ tis greater than the set time (depending on the function code F10.03; this function is invalid if set to 0), it will be regarded communication timeout. Fig. 6-37 Schematic Diagram of Communication Timeout Example of this function: If the master station must send data to a slave station (e.g. #1) within a certain period, you can use the communication timeout function of#1 slave station and set F10.03>T.
The communication timeout protection will not be triggered during normal communication. However, if the master station does not send data to #1 slave station within the specified time T, and this lasts for more than the set value of F10.03, a communication protection ( Ei6 ) will be reported. Once informed ofthe “communication protection of#1 slave station”, the staffcan conduct troubleshooting. * The set value of F10.03 must be greater than the set time T, but must not be too large, in order to avoid adverse effects arising from too long operation in the protection status. * F10.03 should be set to be invalid under normal circumstances.
This parameter will be set only in the continuous communication system to monitor the communication. 165 Start Bit Valid Data Check Bit Stop Bit 1 7 6 5 4 3 2 1 0 N/O/E 1 Function code Function code name Parameter description Unit Default setting Attribute F10.03 Modbus communication timeout 0.0 to 60.0; 0.0: invalid (also valid for master-slave mode) s 0.0 ● Function code Function codename Parameter description Unit Default setting Attribute F10.04 Modbus response delay 1~20 ms 2 ●