All power levels in dBm. Ensure ONU receive power is within the acceptable range for reliable service. Values outside these ranges may cause service issues or damage to equipment.
GPON Power Levels
Per ITU-T G.984.2 specification
Downstream
Wavelength: 1490nm
Data Rate: 2.488 Gbps
Upstream
Wavelength: 1310nm
Data Rate: 1.244 Gbps
Class B+
Most Common
Max Budget
28 dB
| Parameter | Min (dBm) | Max (dBm) |
|---|---|---|
| OLT Transmit Power | 1.5 | 5.0 |
| ONU/ONT Receive Sensitivity | -28.0 | -8.0 |
| ONU/ONT Transmit Power | 0.5 | 5.0 |
| OLT Receive Sensitivity | -28.0 | -8.0 |
Max Split: 1:64
Class C+
Most Common
Max Budget
32 dB
| Parameter | Min (dBm) | Max (dBm) |
|---|---|---|
| OLT Transmit Power | 3.0 | 7.0 |
| ONU/ONT Receive Sensitivity | -32.0 | -8.0 |
| ONU/ONT Transmit Power | 0.5 | 5.0 |
| OLT Receive Sensitivity | -32.0 | -8.0 |
Max Split: 1:128
Field Troubleshooting Quick Reference
Good Signal
ONU Rx: -8 to -25 dBm (GPON)
ONU Rx: -9 to -26 dBm (XGS-PON)
Marginal
ONU Rx: -25 to -27 dBm (GPON)
May experience intermittent issues
Too Low / Too High
Below -28 dBm: Signal too weak
Above -8 dBm: May damage receiver
BIP Errors
Should be 0. Any sustained errors = dirty/damaged fiber path
FEC Corrected
Low counts OK. High = marginal signal. Uncorrectable = problem
GEM Errors
Should be 0. Any errors = serious issue requiring investigation