ePMP Force 300-25 PoE Compatability

I have a Point to Point link established for around a Year now using a Pair of Force 300-25 . It’s working fine and is delivery 99Mbps consistently.

We have upgraded our link capacity to 300Mbps.

Issue is we have only Telecom DC -48v power and we have DC PoE switch providing power to other APs (Ubnt and Mikrotik). These other devices have straight polarity.

But Cambium Force 300-25 have reverse polarity.

Going through the Cambium Forum Force 300-25 PoE Rev & Straight Polarity, Where it specifies that Devices Manufactured after May-2018 are compatible with Both Reverse and Straight polarity PoE…

Extracted from Above link

  • Here is the how you can identify if your F300 will work with both polarities:

Check 3rd and the 4th letters on the MSN (Serial number of the device) - E6UA02KRCLXX.

  • If the 3rd Letter is either {V,W,X,Y,Z}
  • If the 3rd letter is U and 4th letter is either {E,F,G,H,J,K,L,M}

Devices with other MSNs will support reverse polarity only

Now my devices have MSN codes as follows.:

1)Point A:
MSN : E6VG08FR3W90
Firmware version : U-Boot IPQ40xx 2012.07.26 (Nov 22 2018 - 16:17:27)
Software version : 4.1.4

2)Point B:
Firmware version : U-Boot IPQ40xx 2012.07.26 (Nov 22 2018 - 16:17:27)
Software version : 4.1.4

From the above link can we make sure that these 2 devices can be powered using Poe from straight polarity as is with other APs on this site.??

Yes, you are right. Both the devices will work with both polarities.

Thank you for your confirmation…

Nearly all the Force300’s (except for the first couple builds) are polarity agnostic. It’s good to check, but mostly all of them are ± or -+ just fine. HOWEVER, you’ll still want to be sure about your voltages… a Force 300-25 is a 30v device, not a 48v/56v device.


It is an important note! We have some customers burned their F300.

Sure @ninedd , Thanks for reminding.
We have PoE switch with 48vdc input which gives straight polarity PoE 24vdc output …, Which I hope us sufficient to run up the Force 300-25


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