Precautions during control
■Absolute position system (ABS)/Incremental system (INC)
When using FR-A700 series, absolute position system (ABS) cannot be used. Even though "1: Enable (absolute position
detection system)" is set in the servo parameter "Absolute position detection system (PA03)", the servo amplifier operates as
• When the Simple Motion module is powered ON, home position return request is turned ON and the current feed value is
set to 0. (The current feed value is also set to 0 if only the power of inverter is turned OFF to ON.)
• The warnings at absolute position system "Home position return data incorrect" (warning code: 093CH) and "SSCNET
communication error" (warning code: 093EH) are not detected.
Control modes that can be used are shown below.
• Position control mode (speed control including position control and position loop)
• Speed control mode (speed control not including position loop)
• Torque control mode (torque control)
However, it is not available to switch to continuous operation to torque control mode of expansion control "Speed-torque
control". If the mode is switched to continuous operation to torque control mode, the error "Continuous operation to torque
control not supported" (error code: 19E7H) occurs and the operation stops.
"1: Feedback torque" cannot be set in "Torque initial value selection (b4 to b7)" of "[Pr.90] Operation setting for speed-torque
control mode". If it is set, the warning "Torque initial value selection invalid" (warning code: 09E5H) occurs and the command
value immediately after switching is the same as the case of selecting "0: Command torque".
The driver communication is not supported. If the driver communication is set in a servo parameter, the error "Driver
communication setting error" (error code: 1C93H) will occur when the power is turned ON.
■Control mode switching of speed-torque control
The axis connected with FR-A700 series takes more time to switch the control mode than the axis connected with the servo
Position control mode Speed control mode
Speed control mode Position control mode
Position control mode Torque control mode
Torque control mode Position control mode
Speed control mode Torque control mode
Torque control mode Speed control mode
FR-A700 series detection error/warning
When an error occurs at FR-A700 series, the error code is stored in "[Md.23] Axis error No.".
The alarm number of FR-A700 series is stored in "[Md.114] Servo alarm". However, "0" is always stored in "[Md.107]
Parameter error No.".
Confirm the specifications of FR-A700 series for details of errors and warnings.
Appendix 3 Compatible Devices with SSCNETIII(/H)
Switching time at the servo amplifier use
6 to 11 ms
Switching time at FR-A700 series use
19 to 24 ms