 1) Yes you should have no issues adding the 5524P to the current stack. Just make sure the firmware is up to date.  www.dell.com/.../powerconnect-5548  More stacking information can be found on page 43 of the user's manual  support.dell.com/.../en_ug.pdf  2) Looking at the owners manual, it appears that when using a PoE switch it is recommended to use a EPS-470 or MPS-600. The 5524P has a 600w power supply, while the RPS720 supplies 180w of power.   3) No, one PoE switch cannot power another PoE switch. Here is some information on what devices can be powered by a PoE switch.  PoE can be used in any network that deploys relatively low-powered devices  connected to the Ethernet LAN. PDs are devices that receive power from the  PowerConnect power supplies, such as:  • IP phones  • Wireless access points  • IP gateways  • Audio and video remote monitoring devices  4) Yes you can have a uplink connection from one 5524P to another 5524P, but this connection is for data, not to power the device.  Hope this information helps. Thanks.
Hello All, I currently have 2x5548 (non-PoE) switches stacked with HDMI.  Both are being powered by 1xRPS720 unit. 1)  Can 5524P will be able to join the current stack? 2)  Can I supply power to 5524P with existing RPS720? 3)  Can I supply power to another 5524P from a port in 5524P?   eg.  I have 5524P (let's call it SW1) uplinked to a port in another 5524P (SW2).    Thank you.  
Adding PowerConnect 5524P to 2xPC5548 Stack 