A B Signal

(TB:1) (TB:2) Ground

(TB:3)

Figure 31: 700-Series ASD Connections

Note that although the 700-series ASD also supports the Modbus RTU protocol, the initial ASD firmware did not support the Modbus RTU protocol in 2-wire format. Therefore, using the Mitsubishi protocol may be the only available method to communicate with the gateway (ASD parameter 549 must be “0”). Contact Mitsubishi Technical Support for more information.

The slave response timeout is determined via the gateway’s RS-485 port timeout value setting. If the timeout value is set to 0, a default timeout time of 2s is used.

ASD communication characteristics are dictated by parameters 117-124 (PU port) and 331-341 (RS-485 port). Most of these parameters can be set as desired by the user. However, the following parameters must be set as indicated to successfully connect to the gateway:

Parameter 119/333 (stop bits/data bits) .........Must be set for 8 data bits Parameter 123/337 (wait time setting)............Must be set to 9999 Parameter 124/341 (CR/LF selection)............Must be set to 1 (CR only)

ASD parameter number entry radix is decimal (e.g. 10 = 1010)

Any numerically-addressed parameter defined by the Mitsubishi protocol reference manual is directly accessible (base frequency = parameter #3, etc.). However, some ASD data objects do not have parameter numbers assigned by Mitsubishi. For these data objects, the additional parameter numbers indicated in Table 3 have been assigned. For further information

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