Yaskawa MEMOCON GL120 - Manual (Page 341)

4.8 Other Module
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Note (a) Although the lithium battery voltage check sequence is executed and the re-
sults output when the external power supply (24 VDC) is turned ON, the bat-
tery voltage check is not automatically executed while power is ON and will not
be executed while power is ON unless specifically designated. There will be
no indication given externally even if the voltage of the battery drops while
power is ON. It is therefore recommended that the battery voltage check sig-
nal (CHK) be used to periodically to check the voltage of the lithium battery in
24-hour operating systems. The voltage check, however, will reduce the ca-
pacity of the battery and we therefore recommend that the battery check be
performed no more than once a day.
(b) The status of the lithium battery can also be checked while power is ON by
pressing the battery voltage check switch on the Battery Module. Press this
switch with the end of a fine-point precision screwdriver or similar device.
5) Alarm Display and Output
When a voltage drop is detected for the lithium battery in the Battery Module, external
alarms are generated via both indicators and outputs. The relationships among the sta-
tus of the lithium battery, the indicators, and the outputs are shown in the following table.
Table 4.117 Lithium Battery Status, Indicators, and Outputs
Battery Status Indicators Outputs Conditions
Sufficient capacity “ALARM1” Not lit “ALM1” ON Battery voltage > 3.3 V p y
“ALARM2” Not lit “ALM2” ON
y g
Battery needs to be
l d
“ALARM1” Lit “ALM1” OFF 3.0 V < Battery voltage ≤ 3.3 V y
replaced
“ALARM2” Not lit “ALM2” ON
y g
Absolute encoder data
b d
“ALARM1” Lit “ALM1” OFF Battery voltage ≤ 3.0 V
may not be preserved
“ALARM2” Lit “ALM2” OFF
y g
Note (a) Lithium batteries, by their nature, quickly loose capacity once the voltage be-
gins to drop. Always replace the lithium battery as soon as possible, preferably
within one week after the ALARM1 indicator light.
(b) The status of the indicators and outputs signals of the Battery Module are pre-
served when power turns OFF or until the next time the voltage is checked.
6) Lithium Battery Voltage Measurements
The status of the indicators and output signals can be used to determine when the lithium
battery voltage check is being performed. The relationships among the operating status,
indicators, and output signals are shown in the following table.
Table 4.118 Lithium Battery Status, Indicators, and Outputs
Operating Status Indicators Outputs Remarks
External power supply
ON
“POWER” Lit “PON” ON −
External power supply
OFF or battery voltage
being checked
“POWER”
Not lit
“PON” OFF The status of the ALARM1 and
ALARM2 indicators and the ALM1
and ALM2 output signals is
indeterminate.
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