@Phil: i think 30A pdu should work with 20a outlet. 30A is how much load the PDU could handle, and our outlet only provide maximum of 20A. Correct me if im wrong.
Well here is the deal. a 30 amp pdu can have 24 amp hooked up to it 24/7/365
if you swap out the plug it will connect to your 20 amp circuit and if you do 3 avalon 741's you are fine if you load the 4th one you are not fine.
but if you get this
https://www.ebay.com/itm/Conntek-55705-Power-Strip-250-Volt-7-1-2-Inch-Housing-IEC-C14-Inlet-to-4-IEC-C13/292190479200?https://www.amazon.com/NEMA-6-20P-C13-Power-Cord/dp/B004WJNVH4/ref=sr_1_3?you can do 2 avalon 741's
you can use up to 15amps on the setup. and 2 avalon 741's are about 9-11 amps
with this outlet in your place