B–6

Network Protocol Reference

Appendix B

Network Protocol Reference

Transmission procedure

The transmission between the external control equipment and the inverter takes the procedure below

Query

External control equipment

Response

Inverter

t

Latency time

(silent interval plus C078 setting)

Query - A frame sent from the external control equipment to the inverter

Response - A frame returned from inverter to the external control equipment

The inverter returns the response only after the inverter receives a query from the external control equipment and does not output the response positively. Each frame is formatted (with commands) as follows:

Frame Format

Header (silent interval)

Slave address

Function code

Data

Error check

trailer (silent interval)

Message Configuration: QuerySlave address:

This is a number of 1 to 32 assigned to each inverter (slave). (Only the inverter having the address given as a slave address in the query can receive the query.)

When slave address “0” is specified, the query can be addressed to all inverters simul- taneously. (Broadcasting)

In broadcasting, you cannot call and loop back data.