TESTO REXS, Руководство пользователя

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6 Setting up and installation
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
To switch testo
REXS to run state, set the „RUN“ signal from the test stand control. testo
REXS changes to the last operating point selected. To return to standby mode, clear the
„RUN“ signal. To change the operating point, press the right button when testo REXS is in
„RUN“ state.

Press the right button several times until the display shows the required operating point.
6.5. Note
Note:
It has been examined that pressure shifts in the burner output because slight
shifts in the size and number concentration of the particles generated in the
burner. Pressure shifts may be caused by meteorological atmospheric pressure
variations or operation at a different sea level. Filters as a DUT being loaded
may also lead to increasing burner level.
6.6. Warning
Eye protection:
Always wear protection goggles to protect your eyes in case of severe
malfunctions.
Warning:
Back pressure upstream of the DUT may rise up to 500 mbar. The tubing,
possible dilution air supply and measuring equipment has to be designed to
withstand the over pressure that may occur.
Warning:
Toxic gas hazard. testo REXS burner emits toxic gas, CO and CO
2
. The test
bench has to be installed with HEPA backup filter devices.
Soot Nanoparticles :
Soot particles hazard. testo REXS burner emits soot nanoparticles. The test
bench has to be installed with HEPA backup filter devices.
Warning:
Hot surfaces up to 160 °C. Wear heat protective gloves for any manipulation
close to testo REXS and for any handling with the DUT after a test.
Warning:
Moving parts. Do not touch ignition electrode or feed cylinder during ignition
sequence.
6.7. Test Bench Setup Examples
The following section displays four examples how a test bench, using testo REXS as a soot
nanoparticle source may be set up. Note the recommended lengths of the tubing.
Layout 1: Direct connection to DUT.
Application and specification

appropriate backpressure upstream of the DUT to 100 mbar. In this layout a higher back
pressure may result in pulsation and/or aerosol flow oscillation. The soot size distribution
and concentration may shift

appropriate setup when operating with constant flow rate without any additional dilution

besides the exhaust backup filter, no test bench infrastructure is required
Recommended length
A: 40 cm up to 100 cm lenght
C: When using an exhaust backup filter with tunnel, keep the tube short or use a vertical
exhaust pipe to the ambient.