Omron CJ2 - Power Supply Unit Replacement Time

7 Inspection and Maintenance
7-10
CJ2 CPU Unit Hardware User’s Manual
7-3 Power Supply Unit Replacement
Time
The Power Supply Unit has a built-in electrolytic capacitor. The electrolytic capacitor is impregnated
with electrolytic solution that starts to penetrate the sealing rubber from the time of manufacture. As
time elapses, the internal electrolytic solution continues to evaporate, resulting in decreased electro-
static capacity and deterioration in other characteristics. Over time, the characteristic deterioration of
the electrolytic capacitor prevents the Power Supply Unit from being utilized to its full capacity. In partic-
ular, the speed at which the electrolytic capacitor deteriorates fluctuates greatly with the ambient tem-
perature (generally, a temperature rise of 10°C will double the rate of a reaction, as stated by Arrhenius'
law).
The CJ1W-PA205C Power Supply Unit with Replacement Notification monitors the internal temperature
of the Power Supply Unit while the power is turned ON, and calculates the level of deterioration of the
electrolytic capacitor from the operating time and internal temperature. The replacement notification
function displays the approximate time until the Power Supply Unit will stop functioning at its full capac-
ity due to the characteristic deterioration of the electrolytic capacitor, based on the calculated level of
deterioration. When 6 months are remaining until replacement is required, the alarm output will turn
OFF.
Note The replacement notification function provides an indication of when the deterioration of the electrolytic
capacitor will prevent the power supply functioning at its full capacity. It does not provide information on fail-
ures occurring due to other causes.
z CJ1W-PA205C
Principle of Replacement Notification
Power Supply Unit with Replacement Notification
Model Specifications
CJ1W-PA205C Output capacity: 5 A at 5 VDC, 0.8 A at 24 VDC, total of 30 W
With replacement notification
Power Supply Unit Replacement Notification Module
CJ1W-PA205C
POWER
TEST
ALARM OUTPUT
DC30V, 50mA
NORMAL:ON
ALARM
OFF
L
Replacement notification display (7-segment, red)
POWER indicator (green)
Alarm output (replacement
notification output)
test switch
Alarm output (replacement
notification output)
wiring diagram