SEW MOVIDRIVE MDX60B, User Manual

Page: 103 / 144

Manual – MOVIDRIVE® MDX60B/61B Communication and Fieldbus Unit Profile
103
7
Setting the inverter parameters
SEW Unit Profile
Bit 6 is the handshake bit. It has a different meaning depending on the bus system:
• With SBus 1 (CAN) and set handshake bit (= 1), the response telegram is sent after
the synchronization message (see chapter 5.3.2)
• With RS485 and fieldbus, the handshake bit serves as acknowledgement bit
between client and server when using the cyclic transmission method. The
parameter channel is transmitted cyclically, maybe with the process data. For this
reason, the implementation of the service in the inverter must be triggered by edge
control using handshake bit 6. For this purpose, the value of this bit is toggled for
each new service to be executed. The inverter uses the handshake bit to signal
whether the service has been executed or not. The service was executed if the hand-
shake bit received in the control is identical with the transmitted handshake bit.
Status bit 7 indicates whether it was possible to execute the service properly or if errors
occurred.
Response The response to a parameter setting request is structured as follows:
• The management byte of the response telegram is structured like that in the request
telegram.
• The status bit indicates whether the service was executed successfully:
– If the status bit is set to "0", bytes 4 to 7 of the response telegram will contain the
requested data.
– If the status bit is set to "1", an error code is indicated in the data area (bytes 4 to
7) (see chapter "Incorrect service execution").
Description of the
parameter
services Bits 0 - 3 of the management byte are used to define the individual parameter services.
MOVIDRIVE
®
supports the following parameter services:
No service This coding indicates that there is no parameter service.
Read parameter This parameter service is used to read a drive parameter.
Write parameter This parameter service is used for non-volatile writing of a drive parameter. The written
parameter value is stored non-volatile (e.g. in EEPROM). This service should not be
used for cyclic write accesses because the memory modules allow for only a limited
number of write cycles.
Write parameter
volatile This parameter service is used to write a drive parameter volatile, if the parameter
permits this. The written parameter value is only saved volatile in the RAM of the
inverter, which means it is lost when switching off the inverter. When switching the
inverter back on again, the value that was last written with write parameter will be
available again.
Read minimum This service can be used to determine the smallest drive parameter value (minimum)
that can be set. Coding takes place in the same manner as the parameter value.
Read maximum This service can be used to determine the largest drive parameter value (maximum) that
can be set. Coding takes place in the same manner as the parameter value.