EXFO EPM-500 Power Meter - Manual (Page 17)

EPM-500/ELS-500/EOT-500 12
3. Match the source and power meter wavelengths:
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If the source emits an auto-wavelength signal
or is in auto-switching mode (see
Automatically Detecting Wavelength on
page 14 and Using Auto-Switching Mode on
page 17), the power meter automatically
matches the source wavelength.
³
Press to switch between calibrated wavelengths.
4. Hold down a few seconds. The power meter
stores the currently detected power as the new
reference power.
Reference power is displayed in the top right
corner (in dBm) and current loss reading is
automatically switched to dB.
5. Repeat the procedure for each wavelength you
want to reference (if you use auto-switching mode, the power meter
automatically references wavelengths one at a time).
Note: When using dB units, press to display the current wavelength for a
few seconds. To change this wavelength, press again while it is
displayed.
Measuring Power or Loss
Measuring absolute power or link loss is done the same way, except for the
referencing step.
To perform power or loss measurements:
1. If necessary, perform an offset nulling (see Nulling Electrical Offsets on page 10).
2. Check and clean your fibers appropriately for optimum performance
(see Cleaning and Connecting Optical Fibers on page 9).
3. For loss measurements, reference your power meter to a light source
(see Referencing Your Power Meter to a Source on page 11), then deactivate the
light source.