current too low CRS112-8P-4S power VoIP phone

Hardware MikroTik hardware general
1

Hello,

I’m attempting to power a Grandstream 2170 phone from the new MikroTik CRS112-8P-4S-IN 8 port switch. The datasheet for the phone states a power draw of 5.4W using 802.3af. I’m using the included power supply plugged into the 18-28V side. When I try the 48-57V side, all the ports flash red.

The log outputs:
poe-out, warning ether8 detected poe-out status: current_too_low

Is the 48POW a required purchase if using this switch with 802.3af devices?

2

Yes.

https://i.mt.lv/routerboard/files/1517309147CRS112-8P-wg.pdf

3

Hello,

For 802.3af/at, it requires 42-57v power supply. 18-28v power supply is only for 24v passive poe device. so you can buy a 48v60w power supply together with CRS-112-8P-4S.

4

The 48POW did work, however, the 48V2A96W is the new power supply.