Why would this be done?

[Bellendian]

Been to look at a job today. Pretty straightforward until I got to utility cupboard.
Supply is single phase 100A domestic service, 2pole switchfuse in meter box, SWA submain to cupboard.
Just tried to upload pic but too big.
Bottom line is SWA terminated into metal box.
Standard single phase Wylex board with main switch does non RCD ccts.
Next to it is a Hager 3 phase board with 3 phase 30mA RCD incomer. Multiple single phase ccts fed from 3 phase board, adjacent so busbars must be linked.
My question is Why? What's achieved with this setup that couldn't be done with a single phase stacker? Am I missing something?

 

[Dustydazzler]

Commercial sparks with a left over 3 phase board doing a bit of domestic side work ?

 

[James]

Commercial sparks with a left over 3 phase board doing a bit of domestic side work ?

I actually have something similar in my workshop, 3 phase board with single phase link kit.
Saves cost if I ever want to go 3 phase in there or if I want to run it from 3 ph gen set.

 

[static zap]

Just tried to upload pic but too big.

Ditto , (are we on rations?)