TS electrics overhaul

[alan895]

Hi all,

I'm tuning up a 1988 Nutool 10" contractor saw for a friend of mine in return for him decorating my house last year (he thinks so but I may be keeping it :lol: ), its virtually the same as this old Grizzly G1022 and also one Xcalibur sold but is no longer available (though its still on the Woodford website):

I basically want to improve on a couple of things:
The switch - its exactly the same as the one pictured but the contacts inside the box aren't maintaining the connection to keep the motor running. At any rate I'd like to put on an NVR.
The wiring - from the plug to the saw the flex is a collage of different coloured electrical tape so it needs replacing.

So with that in mind:
1. For the NVR switch I'm looking at which would be most suitable but the motor does not have a rating plate on it, from scouring the 'net similar models all seem to have 1.5hp motors fitted so I'm cautiously assuming that’s the case with this one. Most switches that I've seen only go up to 1.5hp but should I opt for something that’s rated for say 2hp?
2. Maybe its because the saw is so old the flex is pretty hefty and it states on the sleeve that the cores are 2.5mm - should I be replacing it like-for-like?

Finally for whatever reason when the saw is plugged into the mains the motor emits a buzzing sound when its standing idle i.e. not in use - is there something amiss here that I'm not picking up on?

Many thanks

Alan

 

[Steve Maskery]

Hi Alan
It looks as if you have the basis of a decent little saw there.
I can't offer advice on the sparky side, but why not PM Myfordman? He is very knowledgeable about this sort of thing and generous with that knowledge. He'll set you straight.
S

 

[MMUK]

You don't need to go the the expense of buying a NVR unit, all it basically contains are two switches and a relay or contactor. I build my own, it's much cheaper.

 

[n0legs]

Buy this -
http://www.axminster.co.uk/axminster-kj ... wwoddQ8AVg

Good supplier, good product.
Cheap.

 

[SteveF]

that is one nice looking saw

Steve

 

[tool-me-up]

Best thing to do is have a peek at the motor and find the plate on it, it should state wattage, voltage etc and then you canmake better decisions about the cable and switches.

 

[alan895]

Best thing to do is have a peek at the motor and find the plate on it, it should state wattage, voltage etc and then you canmake better decisions about the cable and switches.

As I stated previously there isn't such a plate I can use as a reference at least on the outside, yesterday I had a look to see if there was maybe something on the inside - nothing.

On the plus side my friend says that I can keep the saw as he will be upgrading to a second hand Startrite

 

[carlb40]

Best thing to do is have a peek at the motor and find the plate on it, it should state wattage, voltage etc and then you canmake better decisions about the cable and switches.

As I stated previously there isn't such a plate I can use as a reference at least on the outside, yesterday I had a look to see if there was maybe something on the inside - nothing.

On the plus side my friend says that I can keep the saw as he will be upgrading to a second hand Startrite

Excellent news.

 

[tool-me-up]

Sorry I Missed the part about no plate!
2.5mm Cable is the normal size for electrical sockets in your house so will easily take the wattage of a table saw.
Hack the lead off an old hoover, extension lead, or anything else you have broken and is laid around for spares ( not lighting it is smaller cable )

As for switch if you get something rated to at least 13amp then you are WELL within the rating for a table saw - a simple toggle switch is very cheap http://www.ebay.co.uk/itm/15A-High-Qual ... 19dacd9519

A 2000w motor draws almost 9 amps, 13amps is almost 3000 watts.....

 

[n0legs]

Sorry totally disagree with the above post regarding cables.

I don't normally advise on electrical matters, even though I'm more than qualified to do so, there are to many variables.
In the absence of a positive identification of the wattage or load the machine produces, replace like for like.

 

[tool-me-up]

Sorry totally disagree with the above post regarding cables.

I don't normally advise on electrical matters, even though I'm more than qualified to do so, there are to many variables.
In the absence of a positive identification of the wattage or load the machine produces, replace like for like.

Which is what I said - 2.5mm will be more than enough......


Look at the average current rating for 2.5mm 240v cable - it is usually in the region of 24 AMPS. To use the full rating of this cable would require over 5700 Watts.

If the motor is DEFINATELEY less than 3500w ( around 4.5hp) then 1.5mm will carry the current required.....

 

[MickCheese]

Just an idea.

If you run the motor from 240v and use a fuse in the plug of 3a and it doesn't blow then would it stand to reason a normal Hoover cable would be enough?

If it does blow try a 5a one and keep going up until it does not.

I only throw this out there as a topic of conversation I have absolutely no qualifications and was going to write just common sense but I may have just proved that not to be the case!

Mick

 

[n0legs]

Sorry totally disagree with the above post regarding cables.

I don't normally advise on electrical matters, even though I'm more than qualified to do so, there are to many variables.
In the absence of a positive identification of the wattage or load the machine produces, replace like for like.

Which is what I said - 2.5mm will be more than enough......


Look at the average current rating for 2.5mm 240v cable - it is usually in the region of 24 AMPS. To use the full rating of this cable would require over 5700 Watts.

If the motor is DEFINATELEY less than 3500w ( around 4.5hp) then 1.5mm will carry the current required.....

I'm sorry for the confusion and I'd like to say I will not be drawn into an argument over this.
Maybe I should have done this in my earlier post.
This is the line of your post I most dislike.

"Hack the lead off an old hoover, extension lead, or anything else you have broken and is laid around for spares ( not lighting it is smaller cable )"

Dependent on the load of, for example, "an old hoover" you could end up with a 0.75mm 2 core or 3 core flex.
Max current approx 6 amps.
This is where your advice is flawed.

This is also one of the reasons I do not give out advice on electrical matters, you cannot be sure how closely someone will follow your advice, their ability ( no offence to the OP ) and their understanding of your method.

I'm sorry if you have taken any offence.

 

[tool-me-up]

Just an idea.

If you run the motor from 240v and use a fuse in the plug of 3a and it doesn't blow then would it stand to reason a normal Hoover cable would be enough?

If it does blow try a 5a one and keep going up until it does not.

I only throw this out there as a topic of conversation I have absolutely no qualifications and was going to write just common sense but I may have just proved that not to be the case!

Mick

Depends how thick the hoover cable is, a lot of smaller hoovers use 1.5mm cores - i meant find more 2.5mm cable from something like an OLD hoover or an extension lead etc

Saying that general rule is if it has a 3-pin plug IT HAS TO DRAW LESS than 13amps as anything above this is supposed to be wired directly and on its own rcd ( breaker ) for example power showers, electric ovens etc.

If it has been running on a 3 -pin plug with a 13amp fuse then 1.5mm cable is suitable as 1.5mm cable is rated to 15amps....

Actually thinking about it if the cable, switch and everything else is rated to 15 amps it will be impossible to do damage these as the fuse in the plug is only 13amps and it will blow a fuse long before anything starts to go wrong.......

Just make sure its earthed properly.

 

[n0legs]

Just an idea.

If you run the motor from 240v and use a fuse in the plug of 3a and it doesn't blow then would it stand to reason a normal Hoover cable would be enough?

If it does blow try a 5a one and keep going up until it does not.

I only throw this out there as a topic of conversation I have absolutely no qualifications and was going to write just common sense but I may have just proved that not to be the case!

Mick

Hi Mick, now you've opened a can of worms :lol:
When I was an apprentice to illustrate conductivity my instructor made the statement he could light a bulb with a circuit made of wet string.
This he did at mains voltage.
Just because it works doesn't mean it's right.

 

[tool-me-up]

I'm sorry for the confusion and I'd like to say I will not be drawn into an argument over this.
Maybe I should have done this in my earlier post.
This is the line of your post I most dislike.

"Hack the lead off an old hoover, extension lead, or anything else you have broken and is laid around for spares ( not lighting it is smaller cable )"

Dependent on the load of, for example, "an old hoover" you could end up with a 0.75mm 2 core or 3 core flex.
Max current approx 6 amps.
This is where your advice is flawed.

This is also one of the reasons I do not give out advice on electrical matters, you cannot be sure how closely someone will follow your advice, their ability ( no offence to the OP ) and their understanding of your method.

I'm sorry if you have taken any offence.

Oh no, no offence taken I should stated 2.5mm cable really! I see your point about giving advice aswell.

In Short O.P if you have everything rated bigger than the fuse in the plug then the fuse is the weak point in the circuit and will protect you from overloading wires and switches.

It does not protect you from electrical shock though so make sure its earthed!

If you find you keep blowing a 13 amp fuse, then this really shouldnt have a 3 pin plug on the end and you should be looking at wiring directly to its own feed and not to the socket supplies, essentially the same way a cooker is done - but this will require you be absolutely sure on the wattage of the machine AND have an electrician fit your workshop with a high amperage take-off point.

 

[n0legs]

Just an idea.

If you run the motor from 240v and use a fuse in the plug of 3a and it doesn't blow then would it stand to reason a normal Hoover cable would be enough?

If it does blow try a 5a one and keep going up until it does not.

I only throw this out there as a topic of conversation I have absolutely no qualifications and was going to write just common sense but I may have just proved that not to be the case!

Mick

Depends how thick the hoover cable is, a lot of smaller hoovers use 1.5mm cores - i meant find more 2.5mm cable from something like an OLD hoover or an extension lead etc

Saying that general rule is if it has a 3-pin plug IT HAS TO DRAW LESS than 13amps as anything above this is supposed to be wired directly and on its own rcd ( breaker ) for example power showers, electric ovens etc.

If it has been running on a 3 -pin plug with a 13amp fuse then 1.5mm cable is suitable as 1.5mm cable is rated to 15amps....

Actually thinking about it if the cable, switch and everything else is rated to 15 amps it will be impossible to do damage these as the fuse in the plug is only 13amps and it will blow a fuse long before anything starts to go wrong.......

Just make sure its earthed properly.

I did say I was not going to argue about this.

The OP has no more information regarding the saw than it was made in 1988, he says there is no rating plate on the motor and that the cables state they are 2.5mm.
You have quoted 1.5mm cable and 15 amp current carrying capacity, but you use the words "if it has been running on a 3 pin plug".
" If " is the problem.
Surely you can see the issue, we do not know.
Hence without knowing, all the information you have given could be unsafe.

 

[n0legs]

Oh no, no offence taken I should stated 2.5mm cable really! I see your point about giving advice aswell.

Okay we're friends again then :lol:

 

[tool-me-up]

Just an idea.

If you run the motor from 240v and use a fuse in the plug of 3a and it doesn't blow then would it stand to reason a normal Hoover cable would be enough?

If it does blow try a 5a one and keep going up until it does not.

I only throw this out there as a topic of conversation I have absolutely no qualifications and was going to write just common sense but I may have just proved that not to be the case!

Mick

Depends how thick the hoover cable is, a lot of smaller hoovers use 1.5mm cores - i meant find more 2.5mm cable from something like an OLD hoover or an extension lead etc

Saying that general rule is if it has a 3-pin plug IT HAS TO DRAW LESS than 13amps as anything above this is supposed to be wired directly and on its own rcd ( breaker ) for example power showers, electric ovens etc.

If it has been running on a 3 -pin plug with a 13amp fuse then 1.5mm cable is suitable as 1.5mm cable is rated to 15amps....

Actually thinking about it if the cable, switch and everything else is rated to 15 amps it will be impossible to do damage these as the fuse in the plug is only 13amps and it will blow a fuse long before anything starts to go wrong.......

Just make sure its earthed properly.

I did say I was not going to argue about this.

The OP has no more information regarding the saw than it was made in 1988, he says there is no rating plate on the motor and that the cables state they are 2.5mm.
You have quoted 1.5mm cable and 15 amp current carrying capacity, but you use the words "if it has been running on a 3 pin plug".
" If " is the problem.
Surely you can see the issue, we do not know.
Hence without knowing, all the information you have given could be unsafe.

He states in first post "he has had it powered on" so its up to him to go look at how he powered it on. Did he put a normal plug on it or did he put something else on it?
Did it come with a normal 3 pin plug and his mate has used it like that for donkeys ( more than likely ) or did he stick his own plug on it.

We might not know - but HE knows, which is why i said IF. Because IF not its a totally different kettle of fish as i said in previous post lol

If he wants to power it in ways other than a 13 amp FUSED plug then he will have to know the wattage - as I said in previous post...

And we could go back and forth all day about it, giving all the information under the sun - but the OP ( no offense ) decides to ignore us both and run it off speaker wire and electrocute himself then who is the silly one?

I know exactly what your getting at, without seeing or knowing the motor / saw its hard to give solid info and its left to the OP to decide on the ifs and buts.

And yes where friends again haha

 

[MMUK]

Depends how thick the hoover cable is, a lot of smaller hoovers use 1.5mm cores - i meant find more 2.5mm cable from something like an OLD hoover or an extension lead etc

Saying that general rule is if it has a 3-pin plug IT HAS TO DRAW LESS than 13amps as anything above this is supposed to be wired directly and on its own rcd ( breaker ) for example power showers, electric ovens etc.

If it has been running on a 3 -pin plug with a 13amp fuse then 1.5mm cable is suitable as 1.5mm cable is rated to 15amps....

Actually thinking about it if the cable, switch and everything else is rated to 15 amps it will be impossible to do damage these as the fuse in the plug is only 13amps and it will blow a fuse long before anything starts to go wrong.......

Just make sure its earthed properly.

1. There is no domestic hoover to my knowledge that uses cable bigger than 1mm.

2. 1.5mm cable is actually now rated for 16A.

3. Saying that a 13A fuse will 100% protect everything on the load side of it and "it will be impossible to damage" the switch or cable is pure folly. Cartridge fuses are not a 100% fail safe against electrical problems. I've come across numerous applications where a plug top fuse has literally fused in circuit.

Please get your facts 100% right before offering advice on something as potentially dangerous as electricity. :roll: