3-1-5
Battery
The battery is not mounted when the product is shipped.
Y
ou need to prepare a battery for the CPU Unit to retain the clock data while the CPU Unit is left pow-
ered of
f for a long period of time.
The following describes the purpose of the battery mounting, the battery model, and the battery-relat-
ed error detection and clock data settings.
Purpose of the Battery Mounting
The battery is used to retain the clock data while the power is not supplied to the CPU Unit. The clock
data is retained by the built-in capacitor whether the battery is mounted or not, but the retention period
depends on the continuous power-ON time of the CPU Unit, as shown below.
Continuous power-
ON time of CPU
Unit
*1
Retention period
during no power
supply at an ambi-
ent temperature of
40°C
100 hours Approx. 10 days
8 hour Approx. 8 days
1 hour Approx. 7 days
*1. This is equivalent to the time to charge a built-in capacitor in which no electric charge is accumulated.
When you use the clock data for programming, use a battery if you cannot ensure the continuous pow-
er-ON time shown above or the power-OFF time is longer than the above power-ON time.
The following data (other than the clock data) is retained in the built-in non-volatile memory, so they
are not lost even if the battery and built-in capacitor are fully discharged.
•
User program
• Set values
• Variables retained during power interruption
• Event logs
Battery Model
The table below shows the model and specifications of the battery that can be used.
Model Appearance Specification
CJ1W-BAT01 Service life: 5 years
For the battery lifetime, refer to Battery Service
Life and Replacement Period on page 7-7.
The clock information is retained during power in-
terruptions.
3 Configuration Units
3-18
NX-series NX1P2 CPU Unit Hardware User’s Manual (W578)