Hi all, I am new here seeking advice on whether there is a quick fix (or something obvious I missed) or if I need to get a spark (easier said than done just now). This is a long read, so I apologise in advance, but looking over the forum most of the time detail is asked for, so I will give as much as I can. At the start of lockdown we bought a new house, due to Covid etc the timeline pushed out and pushed out and finally we moved in at the start of December. One of the attractions of the house was a detached garage with power as I have a hobbyist woodwork shop type set up to go in there. So last week I finally got round to unpacking and installing my machinery in the garage. Static machines are; 1600W Mitre Saw (x2) - one hard start, one soft start 2100W Table Saw - soft start 2200W Planer/Jointer 1600W Router Table 950W Pillar Drill (Induction Motor) 650W Band Saw (Induction Motor) Each machine is accompanied by a shop vac at 1800W. In addition there is a small 30W hifi that runs for backgorund music. Now obviously all of the machines only run one at a time (save for the shop vac which starts up with each machine via a "take off" socket where the wattage allows). Now to the problem, I started making a new outfeed table for the table saw and using the hard start mitre saw I noticed that the lights were dimming very briefly on start-up. Never thought much of it, later I got cold do I plugged in a 2KW fan heater and went about making the table. After about 15 minutes the power went off. So I checked the CU in the garage and it was fine. So went in to the house and found the main CU has a "Garage" MCB (32A) which had tripped. After re-setting, this happened twice again. Each time, it was just random timing. (not like a machine started and it tripped). So I did a bit of investigating of the system. And I found the following; The main CU 32A MCB feeds the garage on what appears to be 4mm SWA (it's diameter is 16mm which seems to tally with 4mm). This SWA is terminated via a gland at a metal garage CU (The earth on the gland "banjo" is to the earth rail via what looks like a M5 galvanised bolt) which houses 2 x 32A and 1 x 6A MCB from a 40A 30mA incoming RCD - (I think that's the right terminology). There are two 6ft LED batten lamps running from a 2 gang metal switch at the door and 2 security lights that seem to be hard wired "always on" to the 6A MCB along with the feed to the light switch (so 2 browns coming from the 6A MCB). Each of the 32A MCB seem to support a ring circuit of sockets on 2.5 T&E, but its' a bit weird. One set of sockets (4 x double and one single) are metal clad surface mounted and the others (8 x double) are recessed into the MDF clad walls using what appear to be plastic lining boxes. I took each socket off to check for loose connections but they all seem fine, each socket has one incoming and one outgoing cable which seems to start and finish at the MCB. Is there an obvious reason for this tripping at the main CU rather than the garage and it's random nature and I can fix this quickly and myself or is there something sinister at play and I need a spark? At the moment there seems to be a bit of a wait for trades people in my area (Fife, Scotland) due to Covid and them just seemingly busy. Very frustrated that I can't seem to use the garage properly after it being my big excitement of buying the house (don't tell the Mrs that!) Apologies for the long post but wanted to give as much detail as I could.