MikroTik

I have some unmanaged poe switches 802.3af with 48V. Single Port's poe can't be switched off.
They're fine for driving Omni5 APs.

However, I noticed in the specs that the hAPac3 only takes 24V on its poe in port (eth1).
Also I did not find a ref to which poe the ac3 supports.

Assuming that it would break if connected to 48V on eth1:

Since eth 2/3 are non poe and the switch is 802.3af I should be able to connect the ac3 on these ports to the switch?

I have some unmanaged poe switches 802.3af with 48V. Single Port's poe can't be switched off.
They're fine for driving Omni5 APs.

However, I noticed in the specs that the hAPac3 only takes 24V on its poe in port (eth1).

To be correct: 12-28V

Also I did not find a ref to which poe the ac3 supports.

It's in the spec. Passive Poe. It will output what it gets in.
No negotiating with whatever is on the other end.

Assuming that it would break if connected to 48V on eth1:

Best case nothing happens since ac3 will not negotiate (so I assume from a safety point of view no power gets delivered from the switch).

Since eth 2/3 are non poe and the switch is 802.3af I should be able to connect the ac3 on these ports to the switch?

Yes. Should be perfectly fine, ports 2, 3 and 4.
Even 1, it will get no power (no negotiation, safety, no power) but if you power the device using other means, it's a port like any other.
Not too sure about 5.