Mitsubishi Electric Melservo-J3 Series MR-J3-B, Instruction Manual

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16. INDEXER POSITIONING OPERATION
16.10 Absolute position detection system
CAUTION
If an absolute position erase alarm (A25) or an absolute position counter warning
(AE3) has occurred, always perform home position setting again. Not doing so
may cause unexpected operation.
POINT
If the encoder cable is disconnected, absolute position data will be lost in the
following servo motor series. HF-MP, HF-KP, HF-SP, HC-RP, HC-UP, HC-
LP, HA-LP, and HF-JP. After disconnecting the encoder cable, always
execute home position setting and then positioning operation.
When the following parameters are changed, the home position is lost when
turning on the power after the change. Execute the home position return
again when turning on the power.
Parameter No.PA06 (Number of gears on machine-side)
Parameter No.PA07 (Number of gears on servo motor-side)
Parameter No.PA14 (Station No. direction selection)
Parameter No.PC07 (Home position return position data)
This servo amplifier contains a single-axis controller. Also, all servo motor encoders are compatible with an
absolute position detection system. Hence, an absolute position detection system can be configured up by
merely loading an absolute position data back-up battery and setting parameter values.
(1) Restrictions
In the absolute position detection system, the following restriction condition applies for the number of gears
on machine-side (parameter No.PA06 CMX) and servo motor speed (N).
When CMX 2000, N 3076.7 r/min
When CMX 2000, N 3276.7 - CMX r/min
When the servo motor is operated at servo motor speed higher than the limited value, the absolute position
counter warning (AE3) occurs.
(2) Specifications
Item Description
System Electronic battery backup system.
Battery
1 piece of lithium battery ( primary battery, nominal 3.6V)
Type: MR-J3BAT.
Maximum revolution range Home position 32767 rev.
(Note 1) Maximum speed at power failure 3000r/min
(Note 2) Battery backup time Approx. 10,000 hours (battery life with power off)
(Note 3) Battery life 5 years from date of manufacture.
Note 1. Maximum speed available when the shaft is rotated by external force at the time of power failure or the like.
2. Time to hold data by a battery with power off. Change the batteries within three years since the operation start regardless of
the power supply on/off. If the battery is used out of specification, the absolute position erased (A25) may occur.
3. Quality of battery degrades by the storage condition. It is recommended to connect the battery to the servo amplifier and
use it in 2 years from the production date. The life of battery is 5 years from the production date regardless of the
connection.