Function; Measuring And Control Sensor System; Control Of The Irradiance; Control Of The Black Standard Temperature - Atlas XENOTEST BETA LM Operating Manual

ATLAS
7.

Function

7.1 Measuring and control
sensor system
The integrated sensor system of the XENOTEST
BETA together with the sensor for test chamber
temperature and relative humidity (fig. 29) and the
XENOSENSIV sensor covers the following items:
1. measuring of the irradiance at sample
level in a range between 300 and 400nm,
2. control and display of the irradiance be-
tween 35 (min.) and 165 W/m² (max.),
depending on the selected filters,
3. measuring of the black standard
temperature at sample level,
4. control and display of the black standard
temperature between ambient °C and
130°C,
5. measuring, control and display of the
test chamber temperature,
6. measuring, control and display of the
rel. humidity.
without XENOSENSIV sensor:
1. control by the relative electrical lamp
power (0 or 53-120%).
100% lamp power corresponds to a nomi-
nal power of 2200 VA. The control range
from 100-120% allows for the lamp ageing.
2. Control by test chamber temperature
(ambient °C to 80°C).
Figure 29: Sensor for test chamber
temperature and rel. humidity
Housing
Sensor head
XENOTEST BETA
Safety hints
Program example on
Function
XENOTEST BETA
Mounting
Screws
Unit set-up
Features
Test set-up
Operating manual XENOTEST BETA LM
7.1.1

Control of the irradiance

The irradiance can be measured in a wavelength
range between 300-400nm and - depending on the
selected filters - can be set in a range between a
min. of 35 to a max. of 165 W/m². During the life-
time of the lamp (1500 hours) the irradiance is kept
constant at the set value.
The irradiance is infinitely variable by the program
control (fig. 4). Deviations of the irradiance are
identified by the XENOSENSIV sensor and
compensated by the electronic control system.
Depending on the selected filter configuration dif-
ferent spectral energy distributions may occur
(figs.19, 20).
7.1.2 Control of the black
standard temperature
The adjustable black standard temperature depends
on the ambient temperature and on the irradiance.
The setting scope covers a range between ambient
temperature and a max.of 130°C. It is measured
with the XENOSENSIV sensor. It is adjusted by
the speed of the test chamber fan, i.e. by the air
flowrate in the test chamber.
7.1.3

Control of the fan speed

The fan speed can be varied in a range between
800-2500 rpm. Adjustment is effected by the pro-
gram control (chap.8.6). A variation of the fan speed
automatically changes the black standard tempe-
rature which results from the preset irradiance, test
chamber temperature and selected filter system.
To increase the black standard temperature it is
necessary to reduce the fan speed and vice versa.
Options and accessory
Unit description
of the XENOTEST BETA
Care and cleaning
Maintenance
Start-up
List of options
and accessories
Page 37