S8VS Datasheet, PDF (9/24 Pages) Omron Electronics LLC – Switch mode Power Supply (Visible and Slim New Din Rail Power Supply)

I Maintenance Forecast Monitor Function
The power supply unit is equipped with electrolytic capacitors.
The electrolyte inside the electrolytic capacitor penetrates the seal-
ing rubber and evaporates as time passes since it is manufactured,
which causes deterioration of characteristics such as decreasing the
capacitance, etc.
Due to this deterioration of the characteristics of the electrolytic
capacitor, the power supply unit decreases its performance as time
passes.
The maintenance forecast monitor function shows an approximate
period left for maintenance of the power supply unit due to deteriora-
tion of electrolytic capacitors. When the period left for maintenance
that the power supply forecasts reaches the set value, an alarm is
indicated and an output signal is triggered.
Use this function to know the approximate replacement timing of the
power supply unit.
Note: The maintenance forecast monitor function indicates an ap-
proximate period left for maintenance, based on deterioration
of the electrolytic capacitor. It does not predict failures caused
by other reasons.
Relationship Between Indicated Values and Output of Set Values
Initial capacity
Capacity level
at replacement
L: Maintenance forecast set value
(See note.) 0.0 to 5.0, 0.5 steps
In case of setting L between 2.5 and 5 years.
(L−0.5)
"1.0" is displayed on the main display for the
duration that the maintenance forecast up to
replacement satisfies the condition 1.0 ≤ T < 1.5.
Capacity of Capacitor
5.0
Main display
Maintenance forecast monitor output
L=2.5
L=0.5
2.5
2.0
1.5
1.0
0.5
0
T: Maintenance time
until replacement
Note: This function can be set only on the S8VS-09024A Model.
I Principle of Operation
The deterioration speed of the electrolytic capacitor varies consider-
ably according to the ambient temperature. (Generally the speed fol-
lows “Rule of Two for every 10°C”; for every 10°C increase in
temperature the rate of degradation doubles according to Arrhenius’s
equation.) The S8VS-0@024A monitors the temperature inside the
power supply, and calculates the amount of deterioration according
to the running hours and inside temperature. Judging by this amount
of deterioration, the power supply will give the alarm indication and
output when the period left for maintenance reaches the set value.
Note: 1. Due to degradation of internal electronic parts, replace the
power supply at least once every 15 years even if indication
and output of maintenance forecast monitor are not issued.
2. The maintenance forecast is accelerated or decelerated ac-
cording to operating conditions. Periodically check indica-
tion.
The numerical value
decreases with time.
I Reference Value
Item
Value
Definition
Reliability
(MTBF)
135,000 hrs MTBF stands for Mean Time Between
min.
Failures, which is calculated according to
the probability of accidental device fail-
ures, and indicates reliability of devices.
Therefore, it does not necessarily repre-
sent a life of the product.
Life
10 yrs. min. The life expectancy indicates average op-
expectancy
erating hours under the ambient tempera-
ture of 40°C and a load rate of 50%.
Normally this is determined by the life ex-
pectancy of the built-in aluminum electro-
lytic capacitor.
Note: The “maintenance forecast” is the service life (the power sup-
ply’s internal temperature is monitored at all times) of the inter-
nal electrolytic capacitor in actual operating conditions, and
varies according to the customer’s operating conditions. 15
years is taken as the maximum period of the maintenance fore-
cast.
Switch mode Power Supply S8VS
L-63