Hi guys

I have a small craft brewery that has just started up. My brewing system is a 50A single phase system, running two 5500w elements at a time. Control panel is wired for single phase.

The brewery is based in a small village shopping centre running on 3 phase and the shopping centre electrician made quite a significant stuff up. I requested an 80A single phase power supply to my brewery so the guy set up my DB board accordingly with the correct breakers etc. except the main power supply cable coming in is rated at 40A, essentially two 4mm wires for the live and neutral. which is connected to a 40A 3 phase DB board further down the line. I have no idea how he did not realise this but he went ahead anyway and apparently did not realise it himself. The cable looked suspiciously thin to me but I trusted him and after a number of successful tests with no issue, the 40A 3 phase breaker began to trip. I'm pretty certain the electrician isn't qualified.

My question is the following... If I can bring a 40A 3 phase power supply into the brewery and make my DB board 3 phase. Would I be able to hook up my single phase 50A control panel for the brewing system to it and be okay? As far as I am aware 3 phase uses less current in relation to wattage versus single phase but as the brewing system panel and wiring to elements is single phase I don't know if it'll make a difference and will still use the 50A, ultimately tripping the 40A 3 phase breaker anyway.

Also keep in mind that this DB also has to run lights, plugs and two compressors pulling 900w each. No geyser. The brewing system doesn't run all day every day of course but there will likely be points when everything may run at the same time.

Appreciate any advice given on the matter