MAINTENANCE  Series 
 
84/99
Edition 2014-07-10  605451EC
 
7.2.3.1  Durability of power fail battery 
The curves in the graph show the estimated life of Ultra Cap PFO in the worst condition (max. sensor 
load = 1 A, valve heating temperature = 150 °C). 
 
If the SPS is not fully loaded (< 1 A) or heating temperature of valve body is lower than 150 °C, the 
corresponding life time curve will be somewhere in between the upper and the lower curve. 
 
Therefore please determine the equivalent maintenance period for replacing the Ultra Cap battery 
(Option board). 
 
 
 
 
 
This graph shows estimated life of Ultra Cap PFO for reference and not as 
guaranteed value. 
 
0
20
40
60
80
100
120
20 25 30 35 40 45 50
Ambient temperature [°C]
Durability [months]
w/o SPS module,
valve unheated
with SPS module,
valve unheated
w/o SPS module,
valve heated
with SPS module,
valve heated