Laguna Fusion 3 Tripping Breaker

[sunnybob]

If it dims the lights, there are a couple of possible causes. The most likely is the new machine is asking for more power than your supply cable can deliver. This will eventually cause the incoming cable to fail (but there is no time limit on that, it could be years). The cure is to upgrade the cable.
The other is that you have a loose neutral connection somewhere in the line. This could be more serious. I have seen several fires caused by loose neutrals. I was actually working on equipment in one shop when a machine caught fire next to me. They had had a complete rewire and the sparky had left the main neutral wire just pushed into the hole. Thats an easy fix, it just needs you to open every box and panel and make sure all the connections are tight. If that worries you, then you should get an electrician to do the work for you.

 

[Spectric]

As I mentioned you have a volt drop due to the cabling being at the limit because as I said my table saw is also 2200 watt, with a 315mm blade and runs from a 13 amp socket and no light diming because the cable is sized correctly. It could be that the length of the cable run was not fully accounted for or not for the loads you now wish to run. In a home workshop enviroment you do not need to provide a supply to run everything as there is only you in it and you cannot use to machines at once, at least not safetly. All these issues with workshop supplies takes me back several years when someone I knew had an electrical problem and wanted me to take a look. Few days later and they contacted me to say they had fixed it, when asked what the problem was they said the fuses. So what was the cause of the fuses blowing, no the fuses were the problem and we fitted 64 amp fuses instead of the 32 amp ones and it is now ok. When I finaly took a look the wiring was overheated and the fuse carriers and retaining screws discoloured, there was a problem but now insufficient current to blow the larger fuses due to the loop impedance being to high.

 

[sunnybob]

I have a friend who solved the problem of his welder blowing fuses on the end of a 50 metre extension lead by putting a solid copper bar in the fuse terminals on the 13 amp plug.
He's quite intelligent in other ways.

 

[sometimewoodworker]

Hi

If the motor spins up fast that suggest a light initial load and therefore lower current. One reason why the current may be higher could be due to volt drop in the wiring, so as Jerome pointed out just changing something to make it work is not always the right solution. If a sparky comes along and fits the C type breaker then you have some confidence that was the right solution and voltage drop is within 5% of supply.

It is actually the in rush current in the motor, the wiring will be unlikely to be the cause as it will be cold at startup so lower resistance. (Unless you were including the motor wiring)

You will need a loop impedance Zs of 0.26 ohms for a 32A D curve to allow a 640A fault current at around 70oC and that is extremely unlikely/impossible to be achievable in a domestic installation.

If you have a TN-C-S the typical Ze is at 0.35 ohms and that is the best case supply. At 0.32 ohms it will pass a 657A at 230v

with a 32A B curve to allow a 160A fault current at around 70oC You need a Zs of 1.1 ohms, that is easily achievable.

with a 32A C curve to allow a 320A fault current at around 70oC again you will probably be able to fit that as long as your Zs does not have a large resistance added to the Ze

However if you have a TNS or TT Supply you will not be able to just fit a type C as for the TNS best/typical fault current is about 278A and for a TT it’s 11A

So unless you have the equipment to test the loop impedance and can calculate the breaker curve you can use, also be able to certify your work, don’t just swap the breaker for one with a higher startup curve.

like for like, is probably safe. But even then it must be an exact swap as the lecky may have had to get an exact inrush spec from the supplier since your wiring maybe borderline.

All this fun stuff is why you pay a good qualified lecky who will take responsibility to ensure you don’t have an early 4th of November, or at least not from the power side.

 

[guineafowl21]

However if you have a TNS or TT Supply you will not be able to just fit a type C as for the TNS best/typical fault current is about 278A and for a TT it’s 11A

Both of these situations, particularly TT as it’s a requirement, can be rectified with an RCD.

 

[sometimewoodworker]

Both of these situations, particularly TT as it’s a requirement, can be rectified with an RCD.

Of course that is a/the way, I never said it wasn’t. That is why you need someone who knows electrical theory, understands exactly what is needed and has the qualifications to sign off the work.

Many users have no idea what the supply is or the limitations of different systems and why you can not just replace a B with a C or D

Many user will insist that do not have their earth bonded to the neutral as it’s usually in the service head where they can’t see it.

 

[sunnybob]

If youre not careful, you could end up like this

 

[Spectric]

So unless you have the equipment to test the loop impedance and can calculate the breaker curve you can use, also be able to certify your work, don’t just swap the breaker for one with a higher startup curve.

Exactly, and the test gear is not cheap, the last lot I brought was Metrel to cover industrial which is what a lot of my work used to be but now taking it easy and playing around with wood, which these forums are supposed to be.

 

[Daniel.l]

When you talk about cabling is it the cabling from my 16amp socket to my fuse box or the large cable from my garage to my house?
I made sure that the armoured cable from the house was capable of running a table saw and an extractor and possibly another machine if someone else was using something. All the electrics were installed around a year and a half ago by the same electrician I got to fit the c type breaker. I may ask him to take a look at it again I do want another 16qmp socket installed for a planer thicknesser I plan on getting. I will be in the workshop this evening I can have a look and check the sockets for lose neutrals if that could be the cause. I wasn't concerned before but now I am a little
There also is a picture of my fuse box in the garage attached above

 

[sunnybob]

The longer the distance between your machine and consumer unit, the greater the stress on the cable when you start something up.
A cable that will happily feed a half dozen 13 amp sockets will be hard pressed to support 2 16 amps.
PLEASE be very careful if you are going to start undoing fittings to tighten screws. Isolate everywhere before you start, even if that means using a torch to see what youre doing. Modern systems are earthed and cross bonded to hell and back and (for example) a 13 amp socket switch is NOT enough isolation.

 

[Daniel.l]

I don't understand how my previous 4hp sip table saw which was a 3000w motor had no problems at all starting or lights flickering and this saw is 2200w.
I'm always over safe when dealing with electrics cant be too careful

 

[AJB Temple]

I think there is a lot more inertia to overcome with bandsaw than a table saw. Of my machines, the one that struggled the most to get going was the bandsaw. Table saw (multico) never had an issue, but it is just spinning up a blade, not two heavy and tensioned wheels.

 

[DBT85]

Is it not a soft start?

 

[Daniel.l]

I tried attaching a 3 sec clip of it starting but it won't upload .
I also attached images of the armoured cable feeding into the fuse box and a left over piece of cable that supplies all the sockets I don't know if the size helps identify them. For some reason 16swa springs to mind but that be completely wrong

 

[guineafowl21]

I tried attaching a 3 sec clip of it starting but it won't upload .
I also attached images of the armoured cable feeding into the fuse box and a left over piece of cable that supplies all the sockets I don't know if the size helps identify them. For some reason 16swa springs to mind but that be completely wrong

The conductor size is normally printed on the armoured cable, if you look closely. Does it run all the way from your house fusebox to the shed? I’ve seen armour stuff spliced on to existing circuits outside, creating a bottleneck. Do you know of any joints in the cable to use up odd bits (again, it has been done)?

Your saw obviously takes a heavy inrush current on start-up, a result of poor design possibly. Most of us will notice a dimming of the kitchen lights when the kettle is switched on. Is your problem worse than this?