Start Command Source And Frequency Command Source During Communication Operation (Pr. 338, Pr. 339, Pr. 550, Pr. 551) - Mitsubishi Electric FR-A720-00030-NA Instruction Manual

Selection of operation mode and operation location
4.23.3 Start command source and frequency command source during
communication operation (Pr. 338, Pr. 339, Pr. 550, Pr. 551)
When the RS-485 terminals or communication option is used, the external operation command and speed
command can be valid. Command source in the PU operation mode can be selected.
Parameter
Name
Number
Communication operation
338
command source
Communication speed
339
command source
NET mode operation
command source
550 *
selection
PU mode operation
551 *
command source selection
The above parameters can be set whenever the communication option is connected. (Refer to page 316.)
* This parameter allows its setting to be changed in any operation mode even if "0 (initial value)" is set in Pr. 77 Parameter write selection .
(1) Select the command source of the Network operation mode (Pr. 550)
 Either the RS-485 terminals or communication option can be specified as the command source in the Network
operation mode.
 For example, set Pr. 550 to "1" when executing parameter write, start command or frequency command from the
inverter RS-485 terminals in the Network operation mode independently of whether the communication option is
connected or not.
CAUTION
 Since Pr. 550 = "9999" (automatic recognition of the communication option) in the initial setting, parameter write, start command
and frequency command cannot be executed by communication using the inverter RS-485 terminals when the communication
option is fitted. (Monitor and parameter read can be performed.)
(2) Select the command source of the PU operation mode (Pr. 551)
 Any of the PU connector, RS-485 terminals, or USB connector can be specified as the command source in the PU
operation mode.
 Set Pr.551="1" to use the RS-485 terminals to write parameters or send start and frequency commands in the PU
operation mode. Set Pr.551="3" to use the USB connector to do those in the PU operation mode.
CAUTION
 The PU operation mode has a higher priority when Pr. 550 = "1" (NET mode RS-485 terminals) and Pr. 551 = "1" (PU mode RS-485
terminals). When the communication option is not fitted, therefore, the operation mode cannot be switched to Network operation
mode.
 Changed setting value is valid when powering ON or resetting the inverter.
Pr. 550 Pr. 551
Setting Setting PU connector
1
2
(initial
0
PU operation mode
value)
3
1
2
1
(initial
PU operation mode
value)
3
1
2
(initial
PU operation mode
9999
value)
(initial
value)
3
*1 The Modbus-RTU protocol cannot be used in the PU operation mode. When using the Modbus-RTU protocol, set Pr. 551 to "2".
*2 When the communication option is not fitted, the operation mode cannot be switched to Network operation mode.
330
Initial Setting
Value Range
0
0
9999
2
Command Source
USB connector
 


PU operation mode
 


PU operation mode NET operation mode
 


PU operation mode
0
Start command source communication
1
Start command source external
0
Frequency command source communication
1 Frequency command source external
Frequency command source external (Frequency command from
2
communication is valid, frequency command from terminal 2 is invalid)
The communication option is the command source when NET
0
operation mode.
1
RS-485 terminals are the command source when NET operation mode.
Automatic communication option recognition
Normally, the RS-485 terminals are the command source. When a
9999
communication option is mounted, the communication option is the
command source.
1
RS-485 terminals are the command source when PU operation mode.
2
PU connector is the command source when PU operation mode.
3
USB connector is the command source when PU operation mode.
RS-485 terminals Communication option
PU operation mode
*1


PU operation mode
*1
NET operation mode
PU operation mode
*1

NET operation mode

NET operation mode
Description
NET operation mode
*2
NET operation mode
*2
NET operation mode
*2
Switching to NET

operation mode disabled


NET operation mode
*2
Communication option
NET operation mode
*2
fitted
Communication option

not fitted
Communication option
NET operation mode
*2
fitted
Communication option

not fitted
Remarks