More relevant, should suchlike electrical inspection reports only be carried out by a registered INSPECTOR, who must have a separate, periodic assessment?.

In the late 1980's Crabtree were looking to replace the outdated (but still widely used) C50 range. What they came up with was the Polestar range and it was a great success in commercial and industrial applications. You can also buy MCB's pre-fitted with a pod in both the Memshield 2 and Memera 2000 ranges. These are usually just the 30mA size but field fit versions are availble is the following sizes: This illustration shows the metal type Wylex consumer unit with the cover/frame in place. Perhaps the visible busbar that I referred to before is the neutral one visible if the frame is removed, near to the main switch. Square D was bought out by Schneider in 1991 and although they changed the appearance of the circuit breakers the later versions will still fit the older boards. Confused? Well it gets worse because by the time that Delta/Eaton decided that they needed to manufacturer some of the older products to keep the peace with customers the British Standard BS3871 had changed. Previously all MCB's had been marked with a ‘Type' (either 1,2,3 or 4) but BS3871 had changed so that Type 1 MCB's were no longer used and Types 2,3 & 4 were now Types B,C & D.

Moulded Case Circuit Breakers (MCCB's)

Fortunately the situation with Bill and MEM MCCB's is not as confusing. Firstly MCCB's are made to a different standard to MCB's, BS60947-2. Whilst that standard has been updated to allow for new technologies it still remains as the current British Standard.

So now you have a range of circuit breakers that are either branded MEM,Delta,Bill or Eaton. They may me marked either Type 2,3,4 or Type B,C,D. Some have a printed wrap around label and some have silk screen printing direct on the MCB. The Wylex fuse box can be converted to miniature circuit breakers (MCB) it needs power off as to change over it exposes the live bus bars and the units are colour coded white = 6A, Blue = 16A, Yellow = 20A and Red = 32A so it is replace colour for colour.

My topics

Memshield 1 – These are a commercial breaker and come in various types (Type 2,3,B,C & D) depending upon the age. Most are M9 rated.