Cisco MR74 Hardware Installation Manual page 10

Remove protective plastic covers from all four N-type RF connectors.
Attach appropriate antennas (and protective boots if included).
4.2.3.2 Aim Antennas
If you are using directional antennas, aim them appropriately to ensure
optimal performance for your specific network topography.
Omnidirectional antennas perform best in a mesh network when oriented
vertically.
4.2.3.3 Powering the MR74 with the Meraki 802.3at Power over Ethernet
Injector (sold separately)
1. Plug the power cord into the PoE Injector and the other end into
wall power.
2. Plug an Ethernet cable that is connected to an active Ethernet
connection into the "IN" port on the injector.
3. Route Ethernet cable from the "OUT" port on the injector to the
Ethernet port in the bay of the MR74.
For more details, see Meraki 802.3at Power Over Ethernet Injector
datasheet.
4.2.3.4 Powering the MR74 with an 802.3at Power over Ethernet Switch
Route Ethernet cable from a port on an active 802.3at PoE switch to the
Ethernet port in the bay of the MR74.
The MR74 is Gigabit Ethernet-capable. To maximize device performance, a
Gigabit Ethernet-capable switch should be used.
4.2.3.5 Attach Power over Ethernet to the MR74
1. Remove the dust cover from the Ethernet port of the MR74.
Unscrew it with a coin or flathead screwdriver.
2. Route the Ethernet cable from the PoE Injector "OUT" port to the
MR74.
3. Install a cable gland on the MR74 end of the cable.
4. Plug the Ethernet cable into the Ethernet port of the Meraki MR74.
a. Connect the cable to the Ethernet port on the MR74.