35,0(6
Cube
20
Revision 01/2019 EN
11.2.2 Minimum energy per single measurement
The energy used for the measurement must achieve a sufficiently high temperature in
the absorber to be recorded with high precision. Energy of about 300 J is generally
recommended, as long as the measurement duration is < 2 s.
Example: With a laser power of 1 kW and an irradiation time of 300 ms, 300 J are
absorbed.
E = P · t = 1 000 W · 0.3 s = 300 J
Tab. 11.1 on page 20 shows information for selecting the energy permissible for a
measurement in conjunction with the absorber temperature.
25
30
35
40
45
50
55
60
65
70
Absorber temperature in °C
Permissible measuring energy in J
1 000
3 000
10
100
10
100
1000
25
30
35
40
45
50
55
60
65
70
ZU
LÄS
SI
GE
M
ES
SE
NE
RG
IE
ABSORBERTEMPERATUR
PWC - Messbereich in Abhängigkeit der Absorbertemperatur
25 °C Ambient temperature
Max. energy input
Min. energy input
The measuring range varies in accordance with the ambient
temperature. To achieve the greatest possible accuracy, the
absorber temperature should be close to the ambient tempera-
ture, particularly when it comes to the measurement of small
amounts of energy (< 200 J).
Tab. 11.1: Measuring range as a function of the absorber temperature
The minimum energy application shows the limit above which a measurement can be
performed with high precision. The maximum energy application value specifies the limit
at which the absorber reaches its reliable limit temperature. The energy, e.g. for multiple
measurements (series measurements) can be distributed across the range shown in
green.
If the absorber temperature is greater than 70 °C, it won’t be possible to take any
further measurements. In this case, please wait until the temperature falls to below
50 °C (depending on the energy application selected). Please take the limit values from
Tab. 11.1 on page 20.
