Sanken SVCO6, Instruction Manual, Page: 263 / 326

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7
7-4 Serial Communication Function
(2) Frequency setting command
●
The frequency setting (O) command provides a function for setting the frequency from a computer, equivalent to
directly setting the frequency from the panel. The set frequency is written into an appropriate frequency-related
function code (F1021, F2101-F2116) depending on the status of signal input into the control circuit terminals (2DF,
3DF and JOG) at that time.
Example) If control circuit terminals 2DF and DCM1 are connected when the inverter has received command O,
the set frequency is written to function code F2102 as the 2nd speed frequency.
Note: Set F1002=22 before setting a frequency using command O or writing data to a frequency-related function code
(F1021, F2101-F2116) using the function code data write (N) command.
(3) Batch operation function
●
The batch operation function allows selected inverters or all inverters connected through a communication line to
be started and stopped simultaneously by a computer.
1) Batch operation of selected inverters
①
Select inverters for batch operation using command a
②
Specify the direction of rotating for inverters using command b for batch operation
③
Transmit command d with ―inverter number 33‖ to simultaneously start the inverters selected using
command a. The inverters return no response to command d.
④
Transmit command e with ―inverter number 33‖ to simultaneously start the inverters selected using command
a. The inverters return no response to command e.
2) Connect the batch operation of all inverters. The operation direction will be preset by command b.
①
Preset the operation direction using command b.
②
Transmit command d with ―inverter number 34‖ and simultaneously start all the connected inverters. The
inverters return no response to command d.
③
Transmit command e with ―inverter number 34‖ and simultaneously start all the connected inverters. The
inverters return no response to command e.
3) Release of batch operation
①
Transmit command c with ―inverter number 35‖ to release the inverters selected using command a from
batch control.
Note: During batch operation, keep in mind the followings:
1) Inverters return no response to command c, d or e.
2) If command c, d or e sent from a computer is not received normally for some reason, the connected
inverter cannot execute the command. Therefore, the computer should transmit an Operation Status 1 (H)
command to each inverter to confirm that whether the inverter is now executing the received command
correctly.
3) For the meanings of inverter numbers 33, 34 and 35, please refer to ―Message format‖. Different numbers
from 1 to 32 are given to inverters connected using a communication line to identify them as message
destinations. ―33‖ to ―35‖ are special inverter numbers indicating that the messages are addressed to all
inverters connected for batch operation.
(4) Automatic alarm function
● If an alarm occurs, the automatic alarm function automatically issues an Automatic Alarm (Z) command to notify
the computer of the alarm. This function enables the computer to detect an inverter alarm immediately.
● An inverter can issue command Z automatically only if an Automatic Alarm Permitted (X) command is received
from the computer. However, if the Automatic Alarm Prohibited (Y) command is received after command X, the
inverter cannot issue command Z.
Note: If automatic alarm is enabled, the inverter automatically issues an Automatic Alarm command in case of an alarm.
Consequently, message collision may occur on a communication line. The causes of message collision and
preventive actions are as follows:
(1) If the computer transmits a command to an inverter and the inverter in which an alarm has occurred issues
command Z simultaneously
①
The computer detects the message collision. Transmit the message again.
②
If the computer cannot detect the message collision, the messages cannot be sent to their destinations
correctly. Therefore, a normal response from the destination cannot be expected.
(2) If an alarm occurs simultaneously in several inverters permitted to issue command Z
①
Since a message collision destroys the messages, the computer will discard the received abnormal
message.
● An alarm permitted inverter automatically issues command Z about every two seconds in case of an alarm. The
automatic transmission stops if an Alarm Reading (A) command is received. If command Z is received, the
computer must transmit command A immediately to the inverter issuing command Z.