YASKAWA E-7S SERVOPACK SGD7S - 5.15 Resetting the Absolute Encoder

5.15 Resetting the Absolute Encoder
5.15.1 Precautions on Resetting
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Basic Functions That Require Setting before Operation
5.15 Resetting the Absolute Encoder
In a system that uses an absolute encoder, the multiturn data must be reset at startup. An
alarm related to the absolute encoder (A.810 or A.820) will occur when the absolute encoder
must be reset, such as when the power supply is turned ON.
When you reset the absolute encoder, the multiturn data is reset and any alarms related to the
absolute encoder are cleared.
Reset the absolute encoder in the following cases.
• When an A.810 alarm (Encoder Backup Alarm) occurs
• When an A.820 alarm (Encoder Checksum Alarm) occurs
• When starting the system for the first time
• When you want to reset the multiturn data in the absolute encoder
• When the Servomotor has been replaced
5.15.1 Precautions on Resetting
• You cannot use the /ALM-RST (Alarm Reset) signal from the SERVOPACK to clear the A.810
alarm (Encoder Backup Alarm) or the A.820 alarm (Encoder Checksum Alarm). Always exe-
cute the operation to reset the absolute encoder to clear these alarms.
• If an A.8  alarm (Internal Encoder Monitoring Alarm) occurs, turn OFF the power supply to reset the alarm.
• Confirm that setup (initialization) is not in progress from any other tool.
5.15.2 Preparations
Always check the following before you reset an absolute encoder.
• The parameters must not be write prohibited.
• The servo must be OFF to reset the absolute encoder.
CAUTION
 The multiturn data will be reset to a value between -2 and +2 rotations when the absolute
encoder is reset. The reference position of the machine system will change. Adjust the refer-
ence position in the host controller to the position that results from resetting the absolute
encoder.
If the machine is started without adjusting the position in the host controller, unexpected
operation may cause personal injury or damage to the machine.
1. The multiturn data will always be zero in the following cases. It is never necessary to reset
the absolute encoder in these cases. An alarm related to the absolute encoder (A.810 or
A.820) will not occur.
• When you use a single-turn absolute encoder
• When the encoder is set to be used as a single-turn absolute encoder (Pn002 =
n.2)
2. If a batteryless absolute encoder is used, an A.810 alarm (Encoder Backup Alarm) will
occur the first time the power is turned ON. After you reset the absolute encoder, the
A.810 alarm will no longer occur.
Information