Dell PowerEdge R520 Technical Manual page 44

Figure 12 details the dimensions of the Dell PowerEdge R520 chassis.
Za with Za without
1
Xa Xb Y Zb Zc
bezel bezel
631.7mm with
cabled PSU
482.4mm 434.0mm 86.8mm 35mm 20.1mm 611.1mm
649.1mm with
redundant PSU
1
Zb goes to the nominal back wall external surface where the system board I/O connectors are located.
The R520 chassis at maximum configuration is 28.2 kg (62 lb).