Instruction manual

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• The MA7200 Modbus manual indicates that control data registers
(0000H..000FH) are read/write, but reading always returns 0.
• All drive parameters may be read at any time, but only Cn parameters can
be written while the inverter is in DRV mode. The inverter must be in PRG
mode to write any other parameters.
• The drive parameters that configure the RS-485 communication
characteristics (baud rate, etc.) do not take effect until the drive is reset.
• Cn parameter changes take effect instantly, while others don't take effect
until the inverter is put back into DRV mode or the parameters are saved
into EEPROM and the inverter is reset.
• The “write to EEPROM” register (0900H) is write-only. Therefore, if this
drive register is mapped to a point in the gateway, this gateway point will
always be flagged as “in error”, as the gateway will always attempt to read
this register as long as a new value is not being written to it. The impact of
this point always being “in error” (if any), is dependant on the protocol used
to access this point.
16.6.2 PA7300
• Set JP1 on the PA-M card to the "RS-485" position.
• Set both SW1-1 and SW1-2 on the PA-M card to the "OFF" position.
• Connect the gateway’s RS485 port "A" terminal to the PA-M card’s TB1 "1"
terminal, the gateway’s RS485 port "B" terminal to the PA-M card’s TB1 "2"
terminal, and the gateway’s RS485 port "SG" terminal to the PA-M card’s
TB1 "E" terminal.
• Note that the default value of drive parameter Cn-31 (time-out check) is
1.0s. Because the minimum timeout time that the gateway’s port can be
configured for is 1s, to avoid nuisance timeout faults on the drive it is
recommended to either set parameter Cn-31 to 0.0s (if timeout checking is
not needed), or to a value of 2.0s or more (if timeout checking is desired).
• If run/stop etc. commands are to come from network, set Sn-08 to XX0X.
• If frequency reference is to come from network, set Sn-08 to XXX0.
• When drive parameter Sn-24 is set to XX00 (no parity), the gateway’s port
configuration must be set to “none / 2 stop bits”.
• Note that the holding register “address / HEX” and “address / DEC”
columns provided in the PA7300 Modbus manual contain the Modbus
“addressed as” (on-the-wire) values, which are always 1 less than the
Modbus “known as” values (which the gateway’s configuration requires).
Therefore, to calculate the “register” assignment that must be programmed
into the gateway, add 1 to the documented “address / DEC” register
number. For example, the PA7300’s “output frequency” register is
documented to exist at decimal register 36. Adding 1 therefore results in a