IAI America PCON-ABU - Manual (Page 26)

8
2.1.1 Backup Battery
The absolute specification uses a secondary battery (nickel-hydrogen battery) to retain absolute counter
data in the FPGA when the power is cut off, and also to supply the power intermittently to the encoder drive
circuit.
(1) Battery Specification
Item Description
Type Cylindrical sealed nickel-hydrogen battery
Manufacturer SANYO Electric Co., Ltd.
Model AB-7
Nominal voltage 3.6 V (1.2 V x 3)
Rated capacity 3300 mAh
Average life 3 years
Weight 190 g
Charge time Approx. 72 hours
Approx. backup time after cutoff of power 4 levels of 5, 10, 15 and 20 days
(2) Charging the Battery
Always charge the battery when the simple absolute unit is started for the first time after the delivery, or
after the battery has been replaced.
The battery in the simple absolute unit is charged automatically while the power is supplied to the controller,
so keep the main power on for at least 72 hours.
The actuator can be moved and its position table changed while the battery is charged. If the power has
been cut off for an extended period (not exceeding the specified backup time), also charge the battery for at
least 72 hours.
* For the specified backup time, refer to 5.1.1, “Piano Switch Settings.”
(3) Replacing the Battery
The battery is a consumable part, which means that its initial characteristics will deteriorate through
repeated charging. If the backup time has become significantly shorter, the battery is reaching its life and
must be replaced.
Although the exact timing of replacement varies depending on the surrounding air temperature and
discharge condition, a rough guide is approximately three years after the battery is connected to the
controller. The battery unit has a label attached to it, showing a date three years from the shipment. Use
this date as a reference.
Caution: (1) Absolute data may be lost if the actuator receives vibration, shock, etc., or the slider, etc.,
is moved while the power is cut off.
When you turn on the power the next time, an absolute encoder error may generate,
indicated by a green RDY/ALM lamp and red STATUS1 lamp. In this case, you must reset
the alarm and perform home return.
While the power is cut off, do not move the slider or rod.
(2) While the battery is charged, the surrounding air temperature affects the charge efficiency.
It is recommended that the surrounding air temperature be kept to normal temperature
(+10 to +30
qC) while the battery is charged.
If the surrounding air temperature exceeds 45
qC, the charge efficiency will drop and the
battery will not be charged sufficiently. An excessively high surrounding air temperature
during charge may also lead to performance degradation or leakage of battery fluid.