PPM1-D and PPM1-PRO-D

The PON Service Activation PON Power Meter is specifically optimized to detect the downstream PON wavelengths 1490 (IEEE 802.3ah/v EPON and ITU-T G.984 GPON), 1550 (IEEE 802.3ah/v EPON) and 1577 (ITU-T G.9807 XGS-PON), with narrow +10nm spectral passbands to provide more precise filtering compared to other PON Power Meters.

When the '1490 + 1577 nm' PON-aware option is selected and an upstream wavelength (1310nm and 1270nm by extension) the following behaviour may be seen:

• 1490nm will show no power reading (LOW), since the signal falls outside the valid detection range for this channel,
• 1577nm may show a power reading because of the internal design of the instrument when in PON Downstream mode.

To obtain an accurate power reading for 1310nm wavelengths, the device should be switched to 'Broadband mode' (PRO models) where this is one of the calibrated wavelengths.