Low Forward Power alarms are usually caused by:
- Voltage drop
- Power supply ripple
- Poor vessel wiring
- Transient voltage dips during transmission
In most cases, the issue is caused by insufficient power being available due to wiring between the battery and the transceiver. However, in a small number of cases, the alarm can also be caused by a hardware issue within the transceiver.
Step 1 — Test with a Stable Power Supply
If possible:
- Disconnect the unit from the vessel supply
- Test using a stable bench power supply or separate battery
If the alarm disappears, the issue is likely related to vessel wiring or supply quality.
Step 2 — Check Cable Size and Length
Undersized or excessively long cables can cause voltage drop during transmission.
AWG (American Wire Gauge) is used to describe wire thickness:
- Lower AWG number = thicker cable
- Higher AWG number = thinner cable
Thicker cable reduces voltage drop and is recommended for longer cable runs.
Please see the table below for recommended cable sizes and maximum cable lengths.
Maximum Length (m) | Maximum Length (ft) | Cable Diameter | Approx. mm² |
|---|---|---|---|
5.66 m | 18.6 ft | 16 AWG | 1.5 mm² |
8.0 m | 26.2 ft | 14 AWG | 2.5 mm² |
12.8 m | 42.0 ft | 12 AWG | 4.0 mm² |
19.4 m | 63.6 ft | 10 AWG | 6.0 mm² |
These recommendations are based on the worst-case current requirements across the supported transceiver range.