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New Member

Catalyst 3750G 24-port PoE


My first thread. I have encounter some incompatibility on catalyst 10/100/1000Mbps POE switches.

My POE Device (PD) cannot be power up by 3750G (PSE). Found out that 3750G uses phantom power on pin 1, 2, 3, 6 which is IEEE 802.3af

Our 3rd party PD which is also IEEE 802.3af (similar to Cisco pre-standard PoE) uses spare pins 4, 5, 7, 8 for power only.

Anyway for the catalyst 3750G to power up using spare pins 4, 5, 7, 8 ?


New Member

Re: Catalyst 3750G 24-port PoE

I don't believe the 3750G supports power over those pairs, according to this whitepaper:

New Member

Re: Catalyst 3750G 24-port PoE

All the while I thought Catalyst supports IEEE 802.3af Type A and Type B.

Type B be is similar to Cisco Pre-standard POE.

Any ideas I can convert Type A to Type B power delivery other than PowerDsine midspan switches ?

The reason i am asking is because I have devices which act as a backup and cannot be powerup until the master fail.

If i use just an injector or midespan switches which is dummy in nature, this will not work.

Best Regards