Not all pods are the same, some have long leads for triple pole boards and some have short leads for use in domestic boards. Also worth mentioning that the pods will fit the Memera 2000 range of MCB's as well but only the part numbers that start ALB or ALC.

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. After 1994 the British Standard of BS60898 came into effect and the range was changed to Types B, C & D and now included double pole mcb's as well. RCBO's were now being widely used and theses were available in Types B & C although it's rare to see Type B in use as most installations were commercial.However, just to add a little confusion, some MCB's were discontinued whilst under the MEM brand but due to complaints from customers, specifiers and electrical wholesalers the company had to start manufacturing again. Some of these products are branded Delta and from 2003 some of these products are branded Eaton when they company was bought out yet again. MEM first started manufacturing circuit breakers in 1965 and were one of the UK's biggest names in circuit protection. Now they go under the trade name of Eaton but still use the MEM name on some products. 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.

In theroy you should test the loop impedance before changing. A 30A fuse will after many hours blow with 32A and in seconds with 100A and there is a curve linking the two. However with a 32A MCB there are two devices built into one. The thermal part works similar to a fuse but is slower than a fuse at high current so there is also a magnetic part which with the B rated MCB will trip between 3 and 5 times the thermal part so looking at 160A to trip it. To ensure a short circuit will trip the magnetic part we have to measure what the prospective fault current will be. Since ohms law comes in here we can actually measure the impedance (AC resistance) and that for a B32 should be 1.37Ω which allows for the volt drop of 5%. 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. All MCCB's in MEM's Memshield 2 range or Bill's Talisman Plus range are branded as such. Even though Eaton bought out Delta in 2003 they maintained the old branding until they came out with the latest range, Memshield 3. Even though they are using the Memshield brand all breakers are now marked as Eaton. Still Confused?Initially the range was made to BS3871 standards so Types 2 & 3 were available from 6A up to 63A in single and triple pole. RCBO's were also available but they were initially referred to as MCB/RCD units as the term RCBO was not really established as yet. A new range of Polestar was launched in 2012 and called Polestar Compact. Although the new range was 16kA rated due to advances in technology it was significantly slimmer and is not interchangeable with the older style. Bill Switchgear was probably one the oldest British electrical brands and was especially known for bigger switching devices like triple pole fuse switches and switch fuses and LV panelboards. The company was aquired by Delta in 1973 who also owned another well known brand, MEM. Memera 2000AD – These have a narrow terminal and only fit boards specifically marked Memera 2000AD. They won't fit in older boards. 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:

How many of these doctored fuseboards still exist without these metal fuse covers, justifying a recall? I am thinking of the fatalities in a Glasgow care home, thought to have been causedAs with MCB's all MCCB's were manufactured by Delta and either branded MEM or Bill. They are identical apart from the logo and and a slight difference in the part number. You won't find any branded Delta, they never used that branding on any moulded case breakers. 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.

More relevant, should suchlike electrical inspection reports only be carried out by a registered INSPECTOR, who must have a separate, periodic assessment?. Domae – This was the final range of MCB's branded as Square D. Unusually they are not the push-fit type which was what Square D was really known for. This range just uses a standard din-rail clips and was a ‘competitive' product aimed purely for the domestic market. Later versions were branded Schneider but are identical to the Square D.

Moulded Case Circuit Breakers (MCCB's)

Delta decided to keep the brands MEM and Bill separate until 1998 when they finally phased out the Bill brand. What most people don't realise is that all the products that were manufactured were identical in both brands. Delta manufactured the products and either labelled them MEM or Bill. Memera 2000 – There are several different styles of MCB's in this range but all will fit any Memera 2000 board.