Expansion 
 
FPΣ User's Manual 
48 
4.3 FPΣ Memory Expansion Unit 
Parts and Functions 
ON
ABC
 
FP
Σ
 memory expansion unit 
A
 
Front view 
B
 
Left side view 
C
 
Right side view 
1
 POWER LED (green) 
2
 BAT LED (red) 
Off: Battery voltage is normal. 
On: The voltage of the battery for memory backup is reduced, or the memory backup switch is 
turned off. 
3
 Memory backup switch 
Switch 1 and 2 must be turned ON to use the backup battery (factory setting is OFF). Without 
backup battery, data is not saved when the power supply is turned off. 
4
 Expansion connector 
Used to connect the unit to the CPU or another expansion unit. 
5
 Expansion hook 
Used to secure an expansion unit.  
6
 DIN rail attachment lever