Exfo PM-1600 High-Speed Power Meter Manual de usuario descargar pdf (Pagina 27)

Acquiring Power Measurements

High-Speed Power Meter 17

Measuring Relative Power

3. Press dB/W/W until the display switches to relative mode in dB (where

the value displayed is equal to the absolute power minus the

previously stored reference power) or in W/W (where the value

displayed is the deviation ratio from the reference). Pressing dB/W

again switches between dB and W/W measurement units for the

relative power and reference value.

When you access relative mode, the PM-1600 displays the last reference

value entered at the current wavelength (to view the reference value, set

the appropriate channel to reference display mode).

However, to display meaningful relative power readings, it is important to

have an appropriate reference value, using appropriate adapters and test

jumpers, and connecting the optical circuit being referenced to a detector

port.

Note: If you set a reference while a correction factor (CF) is active, the reference

measurement will take the correction factor into account.

To set a reference value, two choices are available.

Entering the Current Power as the Reference Value

To enter the current power,

1. If necessary, select the desired channel (PM-1620).

2. If necessary, press

λ to select the appropriate wavelength.

3. Press dBm/W to select the desired measurement unit.

4. Press Ref to use the current power value as the new reference.

Note: Pressing Ref switches the display to relative mode.