NARDA PMM ER9000, User Manual

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Applications 4-5
4.1.4 Guidance on a
preliminary
Measuring
Procedure
A step-by-step example of a conducted test is the following:
1. Connect the EUT to the front panel socket and the mains network to the
rear plug trough a proper isolation transformer. Leave the EUT switched
off;
2. Switch ON the PMM ER9000 and wait for it to be ready;
3. Run the PMM Emission Suite software;
4. Enter the Sweep Mode by clicking the related tab;
5. Set the Display Dynamics to 120 dB;
6. Choose a Reference Level between 100 and 125 dBµV;
7. Click right key onto the Scan Table and choose the B band;
8. The Minimum Attenuation should be 10 dB;
9. Set the Pulse Limiter in the Front End box on the right of the screen, to
protect the input against voltage spikes;
10. The Detector should be Peak;
11. Select the desired phase/line of the LISN in the Ancillary column of the
Scan Table after having chosen the proper LISN model in the Ancillary
box on the right of the screen;
12. With the EUT switched OFF, click the Execute soft button and wait until
the first scan has been finished;
13. Carry out an overview of the whole spectrum and check the by
executing a pre-measurement with peak detector that the ambient RF
disturbances are at least 20 dB below the desired emission levels;
14. If the ambient noises are low enough continue to the next step,
otherwise take all the necessary steps to reduce the ambient
disturbances (e.g. go to a shielded room, etc.);
15. Switch ON the EUT and then Redo Sweep again and wait until the scan
has been finished;
16. Adjust the Dynamic Range and the Reference Level for the most
convenient visualization;
17. If the results are satisfactory select the cursor Marker (or the Multi
Marker ) and fond the Highest Peak(s) and then either click Analyzer or
Manual to enter respectively in Spectrum Mode or in Manual Mode and
deeply investigate the highest signals;
18. If the results of the scan need to be compared to a defined level, select
a Limit , if appropriate, and then measure again.
4.1.5 Remarks and Hints
for Measuring To avoid errors caused by ambient interference, measurements should be
carried out inside a properly certified anechoic chamber or open site
(OATS). Different sites, like basements or other shielded rooms with low
ambient interferences, are often sufficient for a precertification evaluation
and for debug purposes.