492
Replacing User-serviceable Parts
Section 10-2
data area and other data are not correct for the user program, unexpected
accidents may occur.
10-2 Replacing User-serviceable Parts
The following parts should be replaced periodically as preventative mainte-
nance. The procedures for replacing these parts are described later in this
section.
• Battery (backup for the CPU Unit’s internal clock and RAM)
Battery Functions
The battery maintains the internal clock and the following data of the CPU
Unit’s RAM while the main power supply is OFF.
• Retained regions of I/O memory (such as the Holding Area and DM Area)
If the battery is not installed or battery voltage drops too low, the internal clock
will stop and the data in RAM will be lost when the main power supply goes
OFF.
Battery Service Life and
Replacement Period
At 25
°
C, the maximum service life for batteries is five years whether or not
power is supplied to the CPU Unit while the battery is installed. The battery’s
lifetime will be shorter when it is used at higher temperatures.
The following table shows the approximate minimum lifetimes and typical life-
times for the backup battery (total time with power not supplied).
Note
The minimum lifetime is the memory backup time at an ambient temperature
of 55
°
C. The typical lifetime is the memory backup time at an ambient temper-
ature of 25
°
C.
Model
Approx.
maximum lifetime
Approx. minimum
lifetime (See note.)
Typical lifetime
(See note.)
CP1L-M
@@
D
@
-D
CP1L-L
@@
D
@
-D
5 years
13,000 hours
(approx. 1.5 years)
43,000 hours
(approx. 5 years)
Memory Backup Time
Ambient temperature
This graphic is for reference only.
5 yr
4 yr
3 yr
2 yr
1 yr
CP1L CPU Unit
25
°
C
40
°
C
55
°
C
Содержание CP1L - 12-2007
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Страница 13: ...xiv TABLE OF CONTENTS...
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Страница 33: ...xxxiv Conformance to EC Directives 6...
Страница 65: ...32 Function Blocks Section 1 5...
Страница 428: ...395 Clock Section 6 9...
Страница 429: ...396 Clock Section 6 9...
Страница 523: ...488 Troubleshooting Unit Errors Section 9 4...
Страница 531: ...496 Replacing User serviceable Parts Section 10 2...
Страница 563: ...528 Auxiliary Area Allocations by Function Appendix C...
Страница 611: ...576 Auxiliary Area Allocations by Address Appendix D...
Страница 638: ...603 Connections to Serial Communications Option Boards Appendix F Connecting to Unit...
Страница 639: ...604 Connections to Serial Communications Option Boards Appendix F...
Страница 669: ...634 Index...
Страница 671: ...636 Revision History...