HEEELLPP!! Bandsaw tripping breaker

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craigs

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So I just spent the last few hours erecting the new shiny delivery, set the guides, squared everything up, tensioned the blade and done the tracking. made sure everything was closed up, plugged this sucker in, made sure power was on at the fusebox........and......click. nada. just CLICK.

Am i doing something wrong thats idioticly (TM) simple? Its all tested brand new electrics, with a single 16A commando socket connected to a 16amp 30mA B16 breaker backed up with 100A main fuse.

Fore reference the saw is a Laguna 18BX
 
Is it not the type C MCB that is more suited to motor start ups?
The sparky could have fitted a type B for a more prolonged use
if you mentioned using an extractor aswell.
The spark that worked on the folks place fitted a type B for the welder.

Did you try starting the saw without a blade installed?
Or even checking the belt for tightness, slackening it a bit might help if its very tight.
 
Couple of thoughts...

The manufacturer recommends a type-c breaker.
it may well be tight. As ttrees suggests try slackening it all off
anything else running on same circuit at the same time
 
Hi

Nice bandsaw. I would use a type C MCB as its a 3Hp motor but as mentioned remove the load by taking the blade off and trying again.
 
This is what I have, is it as simple as just getting the breaker replaced?

IMG_20200907_190714.jpg
 
Ok I have taken out the blade, gave the lower wheel a smoosh round its of course a wee bit resistant as its new, but still tripping the rcd
 
Doesn’t sound right, slacken the belt right off so it’s just the motor that has to spin, try that, then if it’s still doing that then it sounds like a wiring problem either in the machine or the supply

Aidan
 
im going to assume that B16 means its a type B and not a type C, the motor turns ok by hand, I wouldnt say its freewheeling though. I loosened the belt on the motor, no blade installed and still the same issue.

Ill see if i can get the sparks to come over tomorrow and replace the breaker to a type C and see if that resolves it first
 
So does the machine run or does it trip immediately? Can you turn the wheels easily by hand? (If not then belt is way too tight). If wheels turn OK I would check the wiring in the plug connecting machine to socket, and in the 16amp socket (with mains off). If that is all OK and there is no damage to wiring that you can see, speak to your electrician and the machine supplier unless you are confident doing electrical tests.

I presume the garage sockets are OK (ie no fault with that mini consumer unit). I would also pop the face off the mini CU and ensure that the connections (there are only 3) are secure). Turn off main supply to the Mini CU first - presumably there is a separate breaker in your house consumer unit. If you are not confident, use the master switch to turn off the supply fully. Don't take risks.
 
So does the machine run or does it trip immediately? Can you turn the wheels easily by hand? (If not then belt is way too tight). If wheels turn OK I would check the wiring in the plug connecting machine to socket, and in the 16amp socket (with mains off). If that is all OK and there is no damage to wiring that you can see, speak to your electrician and the machine supplier unless you are confident doing electrical tests.

I presume the garage sockets are OK (ie no fault with that mini consumer unit). I would also pop the face off the mini CU and ensure that the connections (there are only 3) are secure). Turn off main supply to the Mini CU first - presumably there is a separate breaker in your house consumer unit. If you are not confident, use the master switch to turn off the supply fully. Don't take risks.
the rest of the garage electrics are fine, theres definitely power to the saw as (how do i explain this) when you press start theres almost like a medium loud click. It seems to me that its overloading the breaker causing it to trip.
 
Is it not the type C MCB that is more suited to motor start ups?
The sparky could have fitted a type B for a more prolonged use
if you mentioned using an extractor aswell.
The spark that worked on the folks place fitted a type B for the welder.

Did you try starting the saw without a blade installed?
Or even checking the belt for tightness, slackening it a bit might help if its very tight.

I think you are correct , Type C can cope with the initial surge , They are relatively cheap
 
Hi there

These are type B RCBO's and not MCB's! They are not relatively cheap and if you have noticed this board has a main switch and no RCD because the RCD and MCB function are combined in each RCBO. This is the correct and best way to protect your domestic electrics because there is no common RCD to multiple circuits. It used to be the case that a bulb could blow and the RCD trips and you loose everything that is fed by that RCD, then came dual RCD boards and now RCBO's are the way to go, can be as much as £50 each depending on your board ! At the moment I am thinking that there is an issue with your machine,
 
Hi there

These are type B RCBO's and not MCB's! They are not relatively cheap and if you have noticed this board has a main switch and no RCD because the RCD and MCB function are combined in each RCBO. This is the correct and best way to protect your domestic electrics because there is no common RCD to multiple circuits. It used to be the case that a bulb could blow and the RCD trips and you loose everything that is fed by that RCD, then came dual RCD boards and now RCBO's are the way to go, can be as much as £50 each depending on your board ! At the moment I am thinking that there is an issue with your machine,

So would this Type B RCBO be capable of handling the startup of the machine? The likelihood is that if i go back to Laguna about it, I imagine the first question is going to be "is it a type C breaker?" if not then do that first
 
Get your Electrician in, to see if it would be appropriate to change that 16A RCBO to a 20 A, if it is on a radial circuit.
 
I like the video,

The type C is designed to handle the inrush current of an inductive load such as a motor, with no blade and no tension I would not expect this to trip without the motor trying to turn but your video shows instant triping. The issue with RCBO's is that you do not know if it is tripping on current due to inrush or if it is residual due to an earth leakage fault. Now as an electrician I would do something that I would never recomend to any non electrical person and that would be to temporarily bypass the RCBO and use inline protection(I have a fused link wire for this purpose) but this is not an option for yourself. The RCBO is not wired like a MCB and perhaps you may have a wiring issue, the neutral to the load does not come of a common bar, it comes from the RCBO itself with a wire from the RCBO going to the common bar. There is also a small wire that connects to the protective earth point. If you were to think of changing it then the electrician could check this out and being hands on rectify.
 
I like the video,

The type C is designed to handle the inrush current of an inductive load such as a motor, with no blade and no tension I would not expect this to trip without the motor trying to turn but your video shows instant triping. The issue with RCBO's is that you do not know if it is tripping on current due to inrush or if it is residual due to an earth leakage fault. Now as an electrician I would do something that I would never recomend to any non electrical person and that would be to temporarily bypass the RCBO and use inline protection(I have a fused link wire for this purpose) but this is not an option for yourself. The RCBO is not wired like a MCB and perhaps you may have a wiring issue, the neutral to the load does not come of a common bar, it comes from the RCBO itself with a wire from the RCBO going to the common bar. There is also a small wire that connects to the protective earth point. If you were to think of changing it then the electrician could check this out and being hands on rectify.

I was thinking the same, but I wouldn’t have mentioned it, just in case...

My gut feeling (same as yours) is that the motor alone isn’t so large as to trip a B but not a C, so something is wrong in terms of connections

When we design a piece of custom kit we often have a “debug” connector which we wire up so as to bypass the safety switches etc, requires a trick connector to access and our clientele will never use it, but for working out why something isn’t behaving it’s great

Aidan
 
ill see if i can get the electrician to pop in tomorrow to take a look, id rather rule that out before i goto Laguna for advice.

hmmmmm the RCBO next to it is 20A for the sockets......I wonder......I imagine it wouldn't be too difficult to do the 'ol switcharoo
 
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