To use a 110 volt router on 220 volts you will need to purchase a transformer with 220 volt primary and 110 volt secondary windings of sufficient size to run the router. If the proper transformer is used the router will have it's full rated power and run properly. The transformer size should be chosen based on the largest router or load that will be used so that it can handle other smaller loads. It would be best to have an electrician determine the size of this transformer and install it to meet your local electrical codes.

If I had to do this I would plan on installing one large transformer to run the biggest 110 volt router or tool that I would like to use in my workshop and install it permanently, with several 110 volt outlets located in convenient locations around the shop, probably alongside the 220 volt outlets. This would make it convenient to use the 110 volt tools wherever needed.

Charley

 

Virtually every thing in the US consumer market is 110V. For a given HP rating the current draw on the 110V would be double that of the 220V counterpart requireing a larger minimum conductor size. The safety concerns are greater with the 220V as now the deciding factor on current is the resistance presented by the human body and with 220V the current through the body would be double that of 110V presenting a greater hazard.

 

Great! - Thank you both for your replies - Much appreciated

 

Nick, if you go with 110 vac tools you can buy from the US and pay shipping and still be at a lower cost than UK models. This allows you a much wider group of routers to select from too. It strikes me as funny that the pro's use 110 tools and homeowners use 220.

 

It strikes me as funny that the pro's use 110 tools and homeowners use 220.

What has to be borne in mind is that in the UK, there are two main supply voltages available to users, 440V 3 phase and 240 1 phase. They tend to run the 440V lines from a sub-supply and split it into 3 x single phases, running a 1 phase cable down one side of a street and often another (different) phase down the other side. This helps to balance out the load on the sub-transformer. All domestic supplies are 240V unless there is a special reason for needing 440V such as a large motor - few and far between in houses.
Industry is a different matter and uses 440V for large loads and 240V for smaller loads and lighting etc. Even so, when there is a huge amount of lighting in a building, it may be run from separate 240V phases which started off at the dis box as 440V 3 phase. Again, to balance loads.

That leaves the 'normal' user at home with 240V for everything and it's reasonably safe as long as there's adequate fusing/trips etc and special care is taken in wet or explosive/flammable environments.

The 110V use for professionals is a duty of care/health and safety issue, where more than one person is involved and spread over several people, more mistakes are likely. Unlike home 'shops', contractors' equipment is far more likely to be subject to hostile forces such as rain and bulldozers!

Actually, in home workshops, I consider that some industrial practices are a good thing. I have a 100Amp contactor which totally isolates the supply to all power outlets associated with my tools, at the touch of a button. Not only a safety thing, but very convenient - press STOP and close the door, knowing that you can't possibly have left anything turned on by mistake. I even have a 'maintained' exit light so if the power fails, I can see my way past anything sharp on my way out.

 

There are some misnomers regarding voltage ratings on all equipment.
The routers sold in the UK and rated at 110V are sold like that for safety reasons, otherwise the machines are usually identical and will deliver the same horsepower.
The industrial transformers sold for the purpose and usually coloured yellow, convert our 240V mains to 110V. They are usually sealed from water ingress and have a special outlet which will only take a plug designed for 110V use. If you buy one, ensure that the output (in V/A or Watts) is adequate for the tool/s you wish to power. The power plug is circular and coloured yellow for 110V. There is a similar one for 240V, coloured blue. Both are three pin devices with ROUND pins, one of them being a ground (earth) pin. The plugs are not interchangeable for obvious reasons.

There is a BIG issue in importing 110V machines from the USA and that is because they use a different frequency. In the UK it's 50Hz in the US it's 60Hz and that's where you could come unstuck. Apart from the fact that speed will be lower if used in the UK, some motors will overheat very quickly. (Send me a pm if you want a mini-lecture on why this occurs).

An example - I have an American over-the-range microwave oven which I imported and is running from a transformer rated output 110V 2KVA 50Hz. Fortunately the electronics and the Magnetron are not affected by the lower frequency and the turntable motor and fan don't run long enough to overheat, but the clock certainly is affected and runs slow. To convert to 60Hz at that sort of power would cost me in the region of £900, so we keep the display off and adjust our cook timings accordingly.

Another issue of importing from the USA is the cost in shipping and taxes. We have to pay VAT plus a collection fee and over a certain value (I forget) we have to pay Import Tax AS WELL, which can make US imports not such a good deal.
The quality is not in question, nor are the facilities.

If you are happy to buy the correct transformer, then 110V UK goods will be fine, but will probably cost exactly the same as the 240V models. Otherwise, consider very carefully before importing US 110V electricals.

 

The 50/ 60 HZ thing should not be an issue with a universal motor as used in routers. Even most speed control modules should not be frequency sensitive.

An induction motor on the other hand, will run slower, and could very well or even likely overheat with prolonged run time.

Clocks do use the powerline frequency as a time base, so that is an issue. Many electronic device with switch mode power supplies won't care about frequency either, and many can handle 90 -240 volts.

When in doubt, ask the devices manufacture, or in many cases as always... just read the manual

 

Alan, the htz is a non issue with most power tools..

 

ASpeed controllers are an issue, so is speed itself. ALL 60Hz motors will run slower on 50Hz, unless they're designed for dual frequency.
Fortunately digital motors don't suffer the issue and they're becoming more prolific. My PowerPro is brilliant at holding speed.

Not all routers are universal. I have one that has an induction motor.

 

Your are certainly entitled to your opinion, but...

"Universal motors are known to sometimes over-speed, perhaps dangerously and destructively, when run with no load.This article deals with different methods of universal electric motor speed control.

A motor which can be operated either on DC (direct current) or on single phase AC (alternating current) is called a universal motor. On both AC and DC, it gives approximately the same speed and output. Universal motors often run at dangerously high speed when operated at no load. This means that motor speed will be low at full load, but the speed of the motor will start increasing as the load on the motor decreases. Finally at no load, the motor will run at very high speed (perhaps about 20,000 rpm in some cases) and cannot made to run at less than about 2,000 rpm. The speed of universal motor varies just like that of a DC series motor. Being a series wound motor, it has a high starting torque and variable speed characteristics, and if the motor is started at no load, due to its high starting torque it will attain high speed quickly. Thus it is not advisable to start a universal motor at no load."

Quoted from...
How Speed of a Universal Electric Motor is Controlled

I can give you as many other references as you wish:yes4:

Universal motor WILL run on AC or DC and within reason the frequency is not critical. That is why they are called "universal"! Porter Cable used to actually nameplate routers as AC/DC, I can post a picture to prove that if you like! Router speed controls control duty cycle and as such are not frequency dependent, although they will NOT work with DC.... no return to zero to shut them off! Did you every see a transformer on a speed control module(hand held conventional router anyway)?

I as well have a "router" with an induction motor... most folks here call it a shaper. Not hand held though, and does not spin at 20000+ RPM

 

Nick, For purely recreational/home use, look for a 230V unit which should plug into any standard power point in your home/workshop.

I was not familiar with the 110V worksite requirement in the UK until a few years ago, when the concept was explained to me by a Pom who had bought his kit to Australia. As explained to me, at a jobsite the primary contractor or major subcontractor provides one or more large site transformers which individual workers connect the tools they are using to. The output of the transformer is actually two 55V windings connected out of phase to provide 55V-0-55V output. The 0V terminal is earthed. This is effectively a scaled down version of the 110-0-110 system used in the US to power 230V gear.

In use the tools get 110V by connecting between the two out of phase terminals. However, in the event of a distribution/extension/power cable being penetrated on site and a worker coming into contact with a live 55V wire, the incident should not be fatal as the current flowing through the casualties body should not be suffficient to electrocute them due to the reduced supply voltage.

In the event of a cable being cut through sufficiently to expose both 55V lines or one 55V line and the earth line, there should suffficient current flow at the time of slicing to trip circuit breakers or 'safety switches' and isolate the damaged line. Even if someone was holding a conductive tool at the time that the cable was damaged, their exposure should be limited to 55Vfor a brief period as current flow between the two out of phase 55V lines would be limited to the immediate confines of the cable damage until the breakers trip (i.e a quick flash).

To the best of my knowledge this concept is unique to UK.

 

Nick, For purely recreational/home use, look for a 230V unit which should plug into any standard power point in your home/workshop.

I was not familiar with the 110V worksite requirement in the UK until a few years ago, when the concept was explained to me by a Pom who had bought his kit to Australia. As explained to me, at a jobsite the primary contractor or major subcontractor provides one or more large site transformers which individual workers connect the tools they are using to. The output of the transformer is actually two 55V windings connected out of phase to provide 55V-0-55V output. The 0V terminal is earthed. This is effectively a scaled down version of the 110-0-110 system used in the US to power 230V gear.

In use the tools get 110V by connecting between the two out of phase terminals. However, in the event of a distribution/extension/power cable being penetrated on site and a worker coming into contact with a live 55V wire, the incident should not be fatal as the current flowing through the casualties body should not be sufficient to electrocute them due to the reduced supply voltage.

In the event of a cable being cut through sufficiently to expose both 55V lines or one 55V line and the earth line, there should suffficient current flow at the time of slicing to trip circuit breakers or 'safety switches' and isolate the damaged line. Even if someone was holding a conductive tool at the time that the cable was damaged, their exposure should be limited to 55Vfor a brief period as current flow between the two out of phase 55V lines would be limited to the immediate confines of the cable damage until the breakers trip (i.e a quick flash).

To the best of my knowledge this concept is unique to UK.

You are probably right about the UK. I must admit I don't know of other countries who use 110V supplies in this way.

The 'standard' in mechanical engineering tends to be 110V these days as 110V reduces the risk of serious injury from electric shock and is therefore deemed to be 'reasonably practicable'. I'm not sure there is absolute legislation banning 240V.

Certainly on large construction sites the central transformer concept holds true, but there are many 'jobbing' contractors who use only one or two individual transformers, although some of those are supplied with more than one outlet.

I'm not sure about the smaller portable transformers being centre tapped, although it would make sense (there doesn't seem to be much online general information). I also don't have one to hand to check whether it MUST be connected to ground on the primary (input) cable. Many of this type of device are double insulated with no provision for a ground connection and the smaller transformers could be the same. They are also generally "potted" so that they are totally protected from water (important in the construction industry) except for the input and output connectors,which also have spring loaded covers and point downwards, so they can safely be left out in the rain.

In a 'home' situation, there is no great advantage in safety using 110V if your 240V supply comes via a RCD (Earth trip) and I would advocate use of individual RCDs or one main supply RCD in workshop situations. My shop is supplied by a 40Amp cable at 240V and the RCD is at the beginning of the cable. That way, the cable is also protected of someone managed to put a spade through it (even though it's well buried in conduit, with concrete on top of it)! I agree that if you can get a 240V model for the same price as an identical 110V model, there is little point in buying 110V gear.

 

A picture is worth a thousand words!

 

Another non-electrical issue is WARRANTY. If imported, check beforehand that the domestic distributor will honour the imported device's warranty. A lot won't; why should they?

 

Many may honor the actual warranty, bu it's almost certain nobody will pay for the return shipping and back again.

 

As an Electronics Engineer, I would like to make a few corrections. First, 110VAC has not been a voltage rating in the US for over 40 years. 120VAC is the normal posted voltage rating. That being said, There are various motors that are still being produced with other voltages posted on the rating plate. This is because they can comply with UL requirements for posting of HP ratings by passing UL tests at a particular voltage. While that satisfyies the UL requirement, it doesn't prevent anyone from connecting the motor to the standard 120VAC line. To make sure that these motors will not cause any safety issues, UL requires the motors to also be tested at 120VAC +10% and -15%. (102 -132 VAC). They also make them do several other tests like locked rotor, high temp environment, voltage sags, voltage surges, etc. The reason I am pointing this out, is that a standard 2:1 transformer (240VAC to 120VAC) that has enough or Volt Amp (VA or KVA) capacity will work fine with any US power tool when using this in the UK.

As to the frequency (50Hz vs 60Hz) impacting the motor speed, that is a function of the type of motor that is used. If you are using an induction motor, care must be taken to be sure that the motor can run continuously at either frequency. N ot all induction motors will perform well at both frequencies. Some are so tuned for performance at a specific frequency that they will overheat when connected to the other frequency. If an induction motor is rated at both 50Hz and 60Hz, it will run 5/6 of its 60Hz speed when powered at 50Hz. Universal motors will not have an appreciable speed difference. Most tools that use an electronic speed control (like some routers such as my Bosch MK23EVS) on univeral motors will usually include a feedback mechanism to keep the motor running at a constant speed regardless of the load and voltage fluctuations.

One other consideration for power tools, a motor run at 120VAC will draw twice the current as a motor rated at the same power that is connected to 240VAC, regardless of the frequency. This is important to know when connecting to extension cords. You may need a heavier extension cord when using 120VAC motors compared to 240VAC motors. That being said, motors don't typically like to be run on voltages lower than their rating. Consequnetly, using a heavier (lower AWG number) gauge wire for extension cords is always better for the motor. It will run cooler.

 

Thanks, Glenn... well said!

 

My apologies. 110V when quoted in some countries, has just become a generic term for the USA normal domestic line voltage. Unless we are discussing absolutes, many folk in the UK tend to use 110V as a description.

We have the same problem in the UK where the statutory line voltage is 230V, but it gets referred to as 220V, 230V or 240V. Some old equipment is even marked 250V. For the purists, there are allowable percentage variations, although they're not guaranteed.

I'm not absolutely sure, but I think the stepdown transformers for UK contractors equipment does actually have a rated output of 110V. I'll check the rating plate, next time I'm near one.

You make a good point about extensions. Even at 240V, I have a compressor which often refused to start and would blow a fuse, when supplied via an extension cord, even though the extension cord was rated at twice the current of the compressor, the issue of course being the high initial start current.

With all of the stupidity going on in Europe, attributed to non-existent health and safety laws, I'm surprised that we're still using 230V as a domestic supply. They even tried to lay carpet on a DANCE floor in one location, in case a dancer fell over!!!

 

With all of the stupidity going on in Europe, attributed to non-existent health and safety laws, I'm surprised that we're still using 230V as a domestic supply. They even tried to lay carpet on a DANCE floor in one location, in case a dancer fell over!!!

Yep, the UK and the USA are not so different! Could see that happening here! May have for all I know.

 

Excelent reply Glenn, you pretty much nailed it all down.

 

Hi, Nick56.

Welcome to the forum.

It is amazing the quantity of opinions that followed your question. Very professional answers as well. Hope you can make the right decision about your buying.

 

Hi all

Just a couple of points, 110 volts in the Uk is deemed safe because it is actually +55 & -55 volts, ie centre tapped transformer to earth which means that the worst kick someone can get to ground is 55 volts which for a healthy person is not going to kill.

Ac syncronous motors can be run at different frequencies, this is what a variable speed drive does, often first stage converts Ac into Dc before the second stage produces a variable frequency Ac output using the Dc input. The issue is that the rated power is produced at the stated frequency, increasing the frequency, speed results in less power whereas reducing the frequency and slowing the motor can result in overheating because the internal fan is not moving sufficient air, so you need independant cooling.

all the best Roy