PBI Dansensor CheckPoint O2/CO2 - Understanding Response Time (T95); T95 Measurement Explanation

12 User Manual EN CheckPoint O
2
/CO
2
PBI-200616-G 03/2010 COPYRIGHT © PBI-Dansensor A/S
What does “Response time (T
95
)”
mean
According to the specifications on page 3
the O
2
sensor has a Response time (T
95
) of
10 sec.
This means that when performing
consecutive measurements in areas with
large differences in the O
2
concentrations,
the device will reach 95 % of the “true”
value during the first measurement (10
sec.).
Example:
(See illustration below):
• Last measurement was performed in i.e.
20.9 % O
2
• The following value to be measured is
1.0 % O
2
•Difference is:
20.9 - 1.0 = 19.9 % O
2
• The expected read-out value after first
measuring is:
20.9 - (0.95 * 19.9) = 2.0 % O
2
Consequently this means that if there is a
large difference in the O
2
concentrations
between two consecutive measurements,
multiple measurements must be
performed to obtain the most accurate
result.
O reading
[%]
2
time [sec]
T=0
Start value
Difference = Start value "True" value
T valu
95
e = Start value (0.95*Difference)
T value
95
"True" value
T=10
(1. measurement) (2. measurement)
T=20
Difference