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Danny M2Z20/01/2015 03:07:00
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963 forum posts
2 photos

Even a UPS requires maintenance.

As a qualified electronics maintenance engineer (retired) I still look after a few local businesses p.c's. Apart from literally twisting arms to implement sound backup practices, all vital equipment is 'protected' by UPS's.

But the UPS's themseves require periodic inspection and servicing. The batteries do not last forever and so I advise that they should be changed every 3 years. (I do not sell batteries or UPS's btw).

This is what happened to the batteries in a UPS after 4 years in an air-conditioned office.

Notice that the 'valve-regulation' does not appear to have been very successful at protecting the battery.

ups batteries - 1.jpg

Reliability of the electronic boards in our lathes and mills does not depend on where it was made.
It does, however depend upon quality control - Of the assembly, of the components, of the inspection.

It is not unknown for fake, cloned components (such as electrolytic capacitors) to appear in consumer electronics.

Without going to MilSpec extremes how many people are prepared to pay 20%-50% more for a product if it has been built and assembled up to a 'standard' and not down to a price? The bottom end of the market is very competitive. At the end of the day one get's what one is prepared to pay for and after that it's up to the user to provide a reasonable environment.

* Danny M *

Ketan Swali20/01/2015 06:16:31
1481 forum posts
149 photos
Posted by Danny M2Z on 20/01/2015 03:07:00:

Even a UPS requires maintenance.

But the UPS's themseves require periodic inspection and servicing. The batteries do not last forever and so I advise that they should be changed every 3 years. (I do not sell batteries or UPS's btw).

Without going to MilSpec extremes how many people are prepared to pay 20%-50% more for a product if it has been built and assembled up to a 'standard' and not down to a price? The bottom end of the market is very competitive. At the end of the day one get's what one is prepared to pay for and after that it's up to the user to provide a reasonable environment.

* Danny M *

I agree with all of your comments. We change the batteries periodically. Near end of their life our UPSs start beeping to warn us that they need to be checked/changed.

Ketan at ARC

Ketan Swali20/01/2015 06:26:27
1481 forum posts
149 photos
Posted by Robert Dodds on 19/01/2015 23:29:27:

Hi,
I'm one half of a pair of semi detached and historically my neighbour heated on night storage heating so was allocated Yellow phase and I had connection to Blue but we both share the common neutral line over some 50 metres of overhead line to the roadway. There are several crimped joints down this length and about 18 months ago we started to get browns and brights at random times.When I was bright he was brown and then vice versa
I spotted that we could control it to a degee by switching a fair size load (cooker) on or off, called the Western Electric in and they diagnosed one of the crimp connectors gone high resistance (damp getting into them). In effect the neutral line was no longer clamped to 0 volt, it was floating depending on which of us was drawing more current. I saw 280v at this time on my Aldi meter but after the repacement joint it all went away(until another crimp gives way, but then W E said they would have to close the A road whlst they fitted a new run without joints across it ) I suspect some of the fluctuations you see are from these sort of line faults.

Bob D

We lived at the edge of a semi-rural village of Barkby - Leicester for a few years between 1996 and 2004. We had similar problems to you. The electricity board who ever was in fashion at the time changed the old sub-station what ever it was from an old - semi reliable unit to a new one which meet the latest regs.etc.., which turned into a less reliable set-up with more brown outs. Developers have built new houses there now and I wonder if things have improved.

Ketan at ARC

Ketan Swali20/01/2015 07:12:35
1481 forum posts
149 photos
Posted by John Haine on 19/01/2015 22:39:25:

Most electrical household appliances such as washing machines nowadays have electronic speed controllers. Homes abound with electronic devices, many connected continuously to the mains. I'm an electronics engineer by profession so perhaps my house has even more! I have never had any experience of a fault in any of these caused by a "power surge" or voltage spike from the mains. At my office we have probably well over 50 computers, all with switch mode power supplies and probably the majority live 24 hours a day. In previous employers the numbers have been even bigger. Not to mention the quantity of test gear also switched on all the time. Except in server rooms these machines are not supplied from a UPS, nor in a professional electronics environment do we find it necessary to fit surge protectors. Again I have not been aware of any systematic problem caused by the mains supply quality. This is in a small science park in rural Cambridgeshire.

Most of these products, or at least their power supplies, are made in China or other parts of the Far East, but nevertheless function well on UK mains supplies. Since almost all of them have an IEC mains connector they are clearly designed for a global market and must take account of variable mains quality.

On the other hand what is notable is the number of reports on this and other forums of breakdowns of the speed controllers of dc motors on Far Eastern-made hobby machine tools. You can draw your own conclusion, but my opinion based on observation and a degree of professional experience is that the speed controller design is substandard and should be fixed. It isn't rocket science as it's clear that other companies making all kinds of domestic products have mastered it.

All I can say John is that you are lucky.

Please don't always blame the motor or electronics on cheap lathes and mills. Just as you draw on your experience, I draw on mine, but only after speaking with the users who have had the problems. You also have to remember that people on forums who make negative comments, don't always share the full story. Then a small story - request for help - turns into a snow ball debate about fit for purpose. Right or wrong conclusion which you suggest is a matter of opinion, rather than experience of the person or machine. Whilst some have component related issues due to faulty components, this in my opinion is minor compared to user related overload - knowing or unknowing abuse of the machine, and/or dirty power in the U.K.. In the environment of mills and lathes, this is a bigger variable factor to be taken into the equation than general domestic machines. You can consider this to be fact as I do, based on my experience, or disagree with me, as I am a seller, and I would say this wouldn't I. That is up to you .

Sure, control board designs can be improved, and they are, all the time, and machine prices reflect this too.

The cheapest basic brushed motor mini-lathe across the world has the most basic circuit board with little or no overload protection. We don't sell the machine, but we happily sell the boards to competitors customers. The brushless motor mills and lathes have the latest singing and dancing boards with gods know what on them, and the price reflects this. I am sure we could carry on, and the alternative step would be three phase motor with inverter, which may or may not give the same torque as the brushless spec. control board programming through the speed range.

I still stand by my comments about quality of power in the U.K., and it being variable with spikes, across the land. You are lucky to have what it should be in your home and Science Park. May be we and Dunelm - ex-Head Office just across the road are just unlucky. I think they employ over a hundred people there. I will ask their maintenance man how many computers and employees they have the next time he pops his head head out during a spiky brown out . Because of the size of their operation, he has better access to the electricity board engineers then I do, who tell him when things are going to get back to normal. Until the power gets back to normal, he ends up having to run around trying to deal with variable power related problems.

Ketan at ARC

Russell Eberhardt20/01/2015 11:28:54
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2785 forum posts
87 photos

There seems to still be a bit of confusion over what surge protectors and UPSs do.

Surge protectors, such as those sold in DIY shops to protect computers etc., are designed to protect against very short term surges. They use a semiconductor device called a varistor or VDR which will typically clamp the voltage at 650 to 700 V. They can absorb currents of thousands of amps but only for a few microseconds. They will definitely not protect against the overvoltage that occurs when for example the neutral is high resistance or open circuit at the substation. They will give a certain amount of protection against damage caused by lightning induced surges.

UPSs come in various forms. The simplest do not protect against overvoltage at all they only provide standby power. More sophisticated units are available that also give voltage regulation using a tapped transformer.

Having said that, I have had one of Ketan's SX2P mills for a couple of years and it is plugged into the mains nearly all the time. I have had no problems despite living in an area with a high incidence of thunderstorms and having had a strike within 100 m of the house which took out a computer and a router. However this area is very dry and I have never suffered from condensation in the workshop.

Russell.

Gordon W20/01/2015 11:59:21
2011 forum posts

Would it be worth copying an old idea on modern control systems, ie. drill a small hole at the bottom of the enclosure to let moisture out ? Used to be common practice and worked, maybe modern stuff is too sophisticated, just like me.

Muzzer20/01/2015 12:11:53
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2904 forum posts
448 photos

I've fitted data loggers to troublesome sites in different countries where industrial battery chargers were showing high incidences of overvoltage failure. These included Chinese building sites and exposed US golf courses etc where you tend to see large load transients and frequent lightening strikes - you don't get a lot more hostile in terms of environments. Almost invariably, the problems were down to poor infrastructure ie loose connections or in some cases connecting between phases rather than from phase to neutral.

You couldn't (shouldn't) design all products to withstand those conditions (or even worse, continue to operate) without an unrealistic and uncompetitive cost penalty. There is no call for such robustness - I know, having explored it with major OEM suppliers who carry the can for warranty costs.

By law, electrical equipment is supposed to be designed to withstand a variety of transient conditions but like a lot of products, there are good manufacturers (product developers) and poor ones. Having "benchmarked" a wide variety of products, I can attest to the fact that despite the legislation, there are some pretty fragile products out there. It isn't just a question of cost, as you can design to very low cost and still meet the field requirements.

The answer is to buy stuff that matters from reputable sources - suppliers that value their customers' safety and satisfaction - rather than from unnamed hawkers behind unknown shopfronts. There is a good variety of reputable suppliers advertising (and participating) on this site!

Murray

Muzzer20/01/2015 12:35:08
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2904 forum posts
448 photos

Valve regulation (VRLA) isn't a protection mechanism.

With a flooded battery, any overcharging results in water being electrolysed into hydrogen and oxygen and lost. You have to overcharge lead acid batteries to some degree to ensure they are completely charged and all the cells are balanced. The result is that you have to periodically water flooded batteries.

With VRLA batteries, mild, controlled overcharging doesn't produce gassing, as they are recombined and retained within the battery - and some moderate heat is generated. If the charger within the UPS isn't very sophisticated and the battery is repetitively and/or significantly overcharged, a lot more heat is generated and the battery is easily damaged. The charger would ideally identify a damaged or aged battery and stop trying to charge it.

VRLA batteries are less robust and more expensive than flooded batteries - but on the other hand don't need to be watered and won't leak if they aren't abused. That allows them to be used in home, office, hospital and food manufacturing environments for instance.

Murray

Michael Horner20/01/2015 13:36:01
229 forum posts
63 photos

I have a circa 15 year old Chester mini lathe from new. It has lived in an unheated concrete garage, unheated brick garage and is now living the life of luxury in a unheated integral garage. The motor control has worked fine, even abused it by fitting a 5" 3 jaw chuck. It plays up now and again by the motor still running slowly when it is turned off for a short while.

I don't know if the controller is an american designed one but I think it has thyrister control as opposed to FET control. Not been in the electronicics box for a long time, went into tweek the pots for low speed torque etc.

Just put this in for balance.

In my job as service engineer have known smpsu costing more than a minilathe go bang. We were told it was paper dust, then brand new new machines were going pop, hmm.

Cheers Michael.

John Stevenson20/01/2015 14:07:14
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5068 forum posts
3 photos

Personally I don't know what was wrong with the old treadle lathe.

They used to sort the men out from the boys, especially when they got over 20" centres. wink

Nick_G20/01/2015 14:41:20
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1808 forum posts
744 photos

.

Lets get back to our roots.

Steam engine and line shafts to power the whole show. - Wonderful sound so no need for a workshop radio and configured correctly could heat the workshop as a bonus.

Man and machines in perfect harmony. cheeky

Nick wink

Russ B20/01/2015 15:23:04
635 forum posts
34 photos

What sort of affect do you think solar power systems are having to the grid.....

During the day, I'm relatively sure my dads 4kw system produces over 1kw excess on a cold bright January day (not really sunny, just bright) - during the summer over 2kw excess is more likely.

Now, on my street, I'm one of the very few people who don't have solar, I could count but I'd guess it's about 4/5th of houses have it.

Where is all this digital sine wave, domestic voltage power going to be going, can it go back through the transformers to high voltage?

Are the sine waves all in sync?

Neil Wyatt20/01/2015 15:52:50
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19226 forum posts
749 photos
86 articles

> Where is all this digital sine wave, domestic voltage power going to be going, can it go back through the transformers to high voltage?

In principle, yes.

> Are the sine waves all in sync?

Yes, that's the really clever bit of the feed-in electronics.

The latest idea is setting up local smart grids so that, on a road like yours, you can buy and sell electricity within the community cutting out the middle man so you pay less when you buy but get more when you sell. You are still connected to the grid, of course.

Another new idea is smart gear that does things like switch off the freezers and fridges when there's a surge in demand (world cup half time or Corry tea break), as 15-20 minutes of downtime doesn't adversely affect them - dynamic load balancing..

Neil

KWIL20/01/2015 16:05:00
3681 forum posts
70 photos

The other new idea in the so called smart meter era is that the consumed power is measuarble in 30 minute intervals so you can be charged variable rates at high demand periods to persuad you to switch off itemssecret.

John Stevenson20/01/2015 16:14:46
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5068 forum posts
3 photos

The only thing smart about them is the fact that everyone who has had them fitted now pay more.

It;s the old adage : follow the money trail.

Gordon W20/01/2015 16:17:09
2011 forum posts

I worry more about the big wind generators, there are dozens of them around here and a new one 1/2 mile away. What happens when they kick in ? PS very few have been running this last couple of weeks, no wind or gales.

Clive Hartland20/01/2015 17:18:51
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2929 forum posts
41 photos

Gordon, if you want to know what is going to happen to the wind generators when they kick in is see if you can look for what has happened in the USA. There in California they are spread all over the hills facing the Pacific but now after a few years are at a standstill and derelict.

It seems they found that generating wind power was not viable but being paid rent to park it in that place was! Having seen the wind generators off Herne bay all in lines but all not rotating is just an eye sore and false economy I feel, no one wants one any where near them as they emit subliminal noise which is very disturbing.

PS. They fail spectacularly, sparks and flames with bits flying around.

Clive

Mike Poole20/01/2015 18:00:28
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3676 forum posts
82 photos

I drove the length of France a couple of years ago and must have passed 600 or more wind generators, I didn't see one turning.

Mike

John Stevenson20/01/2015 18:12:28
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5068 forum posts
3 photos

If you do see one turning, and turning slowly chances are it's being driven from the grid as these things can't be parked too long in one spot or they brinnel the bearings because the weight is so high.

Another thing is the blades have to be heated in winter to prevent ice forming and putting them out of balance.

The only way these earn money is for whoever has them parked there, again follow the money trail.

in the recent high winds they have all had to be parked up as they can't run, too dangerous.

One thing that is overlooked in this country is tidal power. Whilst the moon is in the sky we will get two tides per day, 4 in some places. And when the tide is out on the west coast it's in on the east.

One company had a lot of success with tidal generation in the Bristol Channel and approached the government for a loan to follow thru but it wasn't forth coming, all the money had been put into wind generation.

Follow the money trail.

**LINK**

So Siemens bought them out for peanuts and are making a big success of it.

Energy costs in this country would be half what they are now if no grants were paid and it's us paying the grants to people like in the link above.

Bob Brown 120/01/2015 18:20:23
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1022 forum posts
127 photos

If it goes to plan and the nimby's do not get in the way **LINK**

Bob

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