Replacing User-Serviceable Parts - Omron SYSMAC CS Series Operation Manual

Replacing User-serviceable Parts

12-2 Replacing User-serviceable Parts
12-2-1 Battery Replacement
Battery Functions
Battery Service Life and Replacement Period
580
expected accidents may occur. Be sure to include the routing tables,
Controller Link Unit data link tables, network parameters, and other CPU
Bus Unit data, which are stored as parameters in the CPU Unit. Refer to
the CPU Bus Unit and Special I/O Unit operation manuals for details on the
data required by each Unit.
2. The simple backup operation can be used to store the user program and
all parameters for the CS1-H CPU Unit, DeviceNet Units, Serial Commu-
nications Units, and other specific Units in a Memory Card as backup files.
A Memory Card and the simple backup operation can be used to easily re-
store data after replacing any of these Units. Refer to the CS/CJ Series
Programming Manual (W394) for details.
The following parts should be replaced periodically as preventative mainte-
nance. The procedures for replacing these parts are described later in this
section.
• Battery (the CPU Unit's RAM-backup battery)
• Output Unit fuses (in Transistor Output and Triac Output Units)
• Output Unit relays (in Relay Output Units)
The battery retains the following data of the CPU Unit's RAM when 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 clock will
stop and the data in RAM will not be stable when the main power supply turns
OFF.
The battery is not installed in a CS1 CPU Unit when it is shipped. Be sure to
install the provided battery in the CS1 CPU Unit's battery compartment before
using the PLC.
At 25°C, the maximum service life for batteries is 5 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 and when power
is not supplied to the CPU Unit for long periods. In the worst case conditions,
the battery will last for only 0.4 years.
The "time that CPU power is ON" in the following table (power supply rate) is
calculated as follows:
Power supply rate =
Total time power is ON/(total time power is ON + total time power is OFF)
The following table shows minimum lifetimes and typical lifetimes for the
backup battery for CS1 CPU Units.
Section 12-2