Member postings for Robert Atkinson 2

Meets the requirement for an isolation switch....

The person who did an EICR (inspection) on my house prior to some upgrade work put a C2 " Potentially dangerous – urgent remedial action required" "fail" on the report for not having an isolator on the shower. They also put a C2 for the live and neutral crossed (actual not colours) on the shower.
Three things wroong with that:
1/ There is an isolator, he just didn't ask about it
2/ There is no requirement for an isolator with a modern shower (isolated element) and RCD.
3/ Worst of all, the swapped L/N should have been a C1 "Danger Present. Risk of Injury. Immediate remedial action required". They should have fixed it or disabled the shower before leaving.

With 4mm2 T&E cable and correct colours at the consumer unit and shower, guess where the crossover was?
Yes, the non-existent isolator switch. This had not been touched since I moved in.

Robert.

The rotating part actuates the stationary switch by a simple lever bearing on a axially moving (and rotaing) surface. Think of a bobweight engine regulator.

Robert.

My bad. Note I put competent in quotes. It appaers that the requirements depend on the registration body. I looked at one a few years ago and it appeared thier minium standard was completing their two day part P course. They did say if you had no experience you also took their 5 day initial course.

To the cynic in me it seemed to be more about making money than ensuring competence. They also sold the multifuntion testers used on their courses...
The cost of the relevant standard BS7671 "Requirements for Electrical Installations" at over £100 seems excessive to me. Note only the IET call them regulations and they are not mandatory. Well there is one exception, The Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020. This is poorly written and specifically refers to the 2018 (18th) edition of BS7671. So when BS7671 is updated it will be requiring compliance to an obsolete standard. It also does not apply to government or local authority properties....

Robert.

You are not correct on "Part P". Some internal domestic work you can do yourself. Anything outside now has to be carried out by a "qualified" person. Some work such as re-wires and new installations need to be notified.
This isnormally done through the electricians "professional" registered body.
In theory you can do it yourself if you can convince your building control officer that you are competent and they do the notification. The time,effort and cot of this route makes it impractical.
Also note that a company only needs one "qualified" person as long as they are prepared to sign off on the others work. My most recent experience of a "competent" contractor was not very good. They were "hobson's choice" due to enforced timescales but were awful.

Robert.

The time delay "relay" is probably a thermal bi-metallic type. A common application for these is fridge compressors. See https://refrigeratorsreviewed.com/refrigerator-compressor-relay-issues-solutions/

Note that the modern PTC type is not suitable for frequent stopping and starting. This is because they take more time to cool down and "reset".

Robert.

Noel,
https://eandt.theiet.org/content/articles/2023/08/catalina-aircraft-to-build-new-versions-of-famous-wwii-seaplane/

Additionally a plummer block almost always has self-aligining bearings. So you would need two and a shaft to make a rigid headstock

Have you thought about using a car hub assembly? Dual taper roller bearings good seals and low cost.The Mk7 transit one looks eay to mount
https://www.ebay.co.uk/itm/123925114485?
You even get a faceplate
https://www.ebay.co.uk/itm/143374557735?

Ther are smaller ones for cars.
You could buy a complete hub carrier / upright with integral bearings and machine it into a headstock.

Robert

Edited By Robert Atkinson 2 on 12/08/2023 09:51:44

Only work I ever did on a Gannett was a bit of cleaning and corrosion prevention on the one that was at the South Wales aircraft museum ( the one at Rhoose not the current one at St Athan) back in the mid 80's

Edit. The Gannett was XA459. She is now at Solway (Carlisle) and finally getting some attention. Funnily enough I also helped with Vulcan XJ823 at Carlise when I worked there in the early 80's

On the taxi flight, there was less coverage of the crash of a Vertical Aerospace prototype during a unmanned test flight at Kemble last week https://www.flightglobal.com/aerospace/vertical-faces-setback-after-vx4-prototype-crashes-during-flight-testing/154475.article

Edited By Robert Atkinson 2 on 12/08/2023 09:37:07

A larger distance between motor and countershaft will not influnce belt wear much. Wear is most dependent on load and pulley size. Bigger pulleys are better.
A longer belt will cause more variation in tension due to stretch and thermal effects. Generally short belts are better.
Do consider a 3 phase motor and VFD. the motor is no different to contempary ones and you can put the VFD in a box. Get a motor with low speed.minmum is 4 pole but I'd use a 6 pole. This won't need so much reduction = bigger motor pulley.

Robert.

Howard, The ML7 (& S7) do not rely on the weight of the motor to tension the belt. Well they shouldn't. There is a tie bar (also called base link) for the motor platform. Theis is used to set the belt tension.
Extract from ML7 manual:





The weight of the motor is suggested as a inital setting but the motor is held by the angled link seen in image above.
Letting the motor move is bad practice.

Robert.

The big issue that is emerging with ChatGPT and the like is that they makes up "facts" to produce an answer. This has included false reports of sexual hassement coplaints against an individual. I believe this was GPT-4 not Chat-GPT but there are a lot of low quality reports about it on the internet.
https://www.lawgazette.co.uk/commentary-and-opinion/lawyers-beware-ais-hallucinations/5115682.article

Robert

Heat pump efficency of 300% is conservative when heating. Almost all of the electrical power input comes into the house as heat so only needs to pump twice the input power. Outside air temperature has little effect on efficency with typical UK winter temperatures. The only real issue is the water output temperature with the air to water pumps the government are pushing. Air to air heat pumps are much better IMHO. You do however still need a water heater. That can be a instant flow gas or electric.
I've been using air-air heat pumps for over 20 years in two properties and have been very happy. I use a miix of gas and electric instant flow heaters for hot water. One other important detail is the use of "inverter" type units. These use the same technology as VFDs and vary the speed of the compressor (and fans on most designs) according to demand. This is more efficent and you don't get the Bang-on Bang-off noise of old fashioned aircon systems.
One reason for pushng air water heatpumps is you can't use them for cooling. I suggest anyone considering heat pumps to forgo the £5000 garant and go for a full Air-Air system with cooling capability. You don't have to use cooling every day or all the time but it's very nice to hae the option.

Robert.

Edited By Robert Atkinson 2 on 07/08/2023 18:18:15

Much of cost and delays to these major projects is due to opposition from various groups and the complex planning approval process.

Nuclear, is currently the only viable mid-term solution to base load power production. This position would be strengthened if their excess power is used to produce hydrogen. This could be used to run gasturbines for peak load response.

There is a huge amount of money being made from carbon off-setting, biomass etc. IMHO there is too much emphasis on hitting numeric targets rather than finding real solutuons. Even without the carbon of harvesting, processing and shipping (often across the atlantic) of wood pellet "biomass" it produces more CO2 per kWh produced than burnng gas....

At last in the news recently there has been some coverage of the shortcomings of the power network to accept additional power into the network and supply it to were needed like motorway EV charging stations.

This is my personal opinion and may not reflect that of my employer or other organisation I may be associated with. (I do some work on this stuff as part of my day job and a disclamer is required).

Robert.

There are a number of problems with this change. Some of the UK legislation has been changed. The presumption is that it will still be changed and if you want too you can UKCA mark. And for a product that won't be sold outside the UK, for whatever reason, that may actually be easier. But what happens when the EU and UK regulations drift apart? If we continue to accept CE marked goods then a CE marked item would have be accepted when it would not meet UK law.
As long as the UK accepts CE marked goods any maker or seller who sells in both markets will only CE mark them. Why even spend time on the paperwork to add UKCA.

So will they ukdate UK law to match EU? Or let / drive them to diverge and let someone else sort out the mess later?

Anyone who voted to leave the EU didn't know what they were doing because they were not told what would happen and clearly some changes that were supposed to happen have not.

We are seeing issues in my day job - aviation. There was a recent change to the regulations around UK CAA design approvals (Part 21J). This was without UK consultation and mirrors a EU (EASA) change. Apparently they think having the Europeans consult on the changes on behalf of the UK industry is OK

This is purely my personal opinion and has nothing to do with my employer and does not represent any view that they may or may not have.

Robert.

But you only pay once. Timpsons offer a lifetime warranties on watch batteries. When it dies take it back and they fit a new battery for free. Took SWMBO's Longines ffor the third time last week.

Edited By Robert Atkinson 2 on 03/08/2023 18:37:33

Volkwagen Audi Group includes Porsche, Skoda and Seat. Many of their parts boxes have multiple logos printed on them.
https://www.cbautoservice.co.uk/vw_audi_group_parts.html

Alternative parts get really creative when they are cheaper and better. An example is the Fiat Croma (mk2) two piece driveshaft. They have a tulip joint which is prone to failure. Also due to low numbers prodced, expensive. The driveshaft from a Vauxhaul Vectra C is much better but the (proper CV) joint is in a different place as is the support bearing. However the gearbox on the Fiat has two bearing mount positions. A shaft and bearing from a scrap Vectra fit's straight on
Not so nice is the electronically controlled power steering pump. New Vectra one is a fraction of the cost of the Croma and appears identical. However it is on the CAN databus system and the codes (address) in the firmware are different. So you can't use the Vectra one.... unless of course you are an electronics engineer and an swap the surface mount chip from the old into the new....

Robert.

Regardless of how the board is marked or wired, it is most important that the fuse and main switch are in the live of the incoming connection.

This is because if they are in the neutral and the fuse blows or the switch is off the machine will appear dead but all the internal wiring up to the fuse or switch will be live and waiting to shock anyone working on the machine.

Robert.

I bought one of these recently:
https://www.screwfix.com/p/croydex-michigan-soft-close-with-quick-release-toilet-seat-thermoset-plastic-white/274jj
and am very pleased with it. It OK on all your points. They have improved the attachments while leaving them adjustable. First it includes a spacer bar / jig so you can set the fittings without the seat attached. Secondly they have added pads of high-strength adhesive foam like 3M VHB. When I saw this I thought it was a bad idea because you only get one chance placing it in contact. But they have a clever design with collapsible spacers. These allow you align everything with bolts finger tight. Then as you tighten the bolts the spacers collapse and the base of the fitting is stuck down. Seat cost £35 so not cheap but not the most expensive. Got SWMBO approval too.

Avoid any seat that says thermoplastic...

Robert.

Edited By Robert Atkinson 2 on 31/07/2023 12:48:36

I doubt the part with the sheared screws is scrap. Worst case is you drill them out and re-tap for M8. The corresponding holes and countersinks in the other part would have to be enlarged as well. Another, possibly better option is a helicoil type repair. A couple of random examples:
https://www.engineeringsupplies.co.uk/m6-x-10-metric-coarse-thread-repair-kit.html
https://www.amazon.co.uk/DAYUAN-M6x1-0mm-Restoring-Compatible-Repairing/dp/B0B48NK2SC/
https://www.machinemart.co.uk/p/040216677/

You drill out with the supplied drill. Tap with the supplied special tap and fit the spring like repair insert.

Robert.