Fuji Electric SPH Series - Retaining Variables During Power Failure; Setting Initial Value for Variable; Restrictions on Variable Names

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Section 1 Specications
(3) Retaining variables during power failure
The variables that are so set as to be retained during power failure (the variables assigned to reMain memory) are reset at cold
start (when started up initially from D300win) and retained at warm start (when started up from D300win or when the unit is
powered up).
There are two methods for retaining variables during power failure:
• Check the [Retain Type] box on the variable worksheet.
a
The variable is assigned to an address out of AT range in the retain memory during compilation.
• Assign the variable to an address within AT range.
Notes:
1) When assigning a variable to a memory, address specication is given priority. Therefore, even when the [Retain Type] box
is checked for a variable for which AT is specied in the standard memory area, the variable won’t not be retained during
power failure (the variable is not assigned to the retain memory.)
2) In the following cases, the data of retain memory is cleared and the unit comes in cold start operation mode.
• When started up for the rst time after user ROM with different memory allocation was installed
• When started up for the rst time after memory backup error occurred
• When started up for the rst time after the resources were initialized
• When started up for the rst time after the data memory in this area was cleared
• During battery-less operation
(4) Setting initial value for variable
When initial value is set for a variable, the set initial value is assigned to the variable when PLC application program is started
(during the rst scan). Initial value is set in the [Initial Value] column on the variable worksheet.
Notes:
When initial values are set, 2.5 steps are consumed for one value from the end of program memory area in order. If there is no
free area in the program area, no initial value can be set for variable.
(5) Restrictions on variable names
• Only a symbol “_” may be used for a variable name. Note that no “_” can follow the variable name.
• No digit can be used at the top of a variable name.
• Up to 30 characters can be used for a variable name.
• No space can be used for a variable name.
• The words reserved for the system (data type names, instruction names, etc.) cannot be used.
Retain memory
AT range
Out of AT range