Omron NJ501-1400 User Manual

6-7
6 Inspection and Maintenance
NJ-series CPU Unit Hardware User’s Manual (W500)
6-2 Replacing the Battery
6
6-2-2 Operation without a Battery
Additional Information
The Low Battery Voltage event is cleared automatically the next time the Controller is turned ON
after replacing the Battery.
NJ-series CPU Units do not support a battery-free operation function such as CJ-series CPU Units. If a
Battery is not connected or the Battery voltage is too low, the following operation occurs.
•A Low Battery Voltage, Battery-backup Memory Check Error, and Real-Time Clock Stopped are
detected.
• The system-defined variable _RetainFail (Power Retention Failure Flag) will be TRUE.
 Retaining or Not Retaining Data in the CPU Unit
Data in the CPU Unit will be retained or not retained as described in the following table according to
whether there is a Battery.
* If the initial value setting is blank, the initial value for the data type is used. For example, the initial value of BOOL
data is FALSE and the initial value of integer data is 0. Refer to the NJ/NX-series CPU Unit Software User’s Man-
ual (Cat. No. W501) for details on the initial values.
6-2-2 Operation without a Battery
Type of data
Power turned ON
Battery No Battery
User program Values before power interruption will be
retained by the built-in non-volatile memory.
Controller Configurations and Setup
Event log
Values before power
interruption will be
retained.
Values before power
interruption will not
be retained.
Clock data Correct values Illegal value
Values of
variables
No Retain attribute Initial values* Initial values*
Retain attribute
Values before power
interruption will be
retained.
Initial values*
AT (allo-
cated
memory)
specifica-
tion
Non-retained areas: CIO and Work Areas Initial values* Initial values*
Retained
areas: DM
Area
Words allocated to Special
Units (and device variables
for Special Units)
Values before power
interruption will be
retained.
Initial values*
Words that are not allocated
to Special Units
Retained areas: Holding and EM Areas
CJ-series Unit memory
Non-retained areas: CIO and Work Areas Cleared to zeros. Cleared to zeros.
Retained areas: Holding, DM, and EM Areas
Values before power
interruption will be
retained.
Unstable

Omron NJ501-1400 Specifications

General

Brand	Omron
Model	NJ501-1400
Category	Control Unit
Language	English