Power Verizon/Frontier ONT with DC supply

Sat 25 December 2021

If you have a Verizon / Frontier ONT (modem), and would like to solely run it on DC power, or would like to drop the bulky CyberPower CA25U16V2 power supply, you should do the following:

  1. Disconnect the power supply
  2. Provide your own means of DC power, for example, some sort of DC UPS. Inject power with the 5.5x2.5 barrel connector (if you have the Y cable with mini-DIN on one side, barrel connector and molex connector on the other side).
  3. Connect a 47 Ohm resistor between grey (BAT) and black (GND). Don't have to be 47 Ohm, but it should be of low resistance.

The ONT does not stricly need 16V. 12V works just fine. Without the resistor, the ONT would shut down WAN port. It only draws around 0.1A at 12V, so any reasonable battery will support it for quite a while...