Fuse blowing BS400

[Gordon T]

Hello all, my new BS400 Record power bandsaw blows its fuse on start up almost every single time I turn it on,(except when I remove the drive belt-no load ). It is supposed to run on a 13 amp 240 v supply but clearly can not cope, what can do to solve this? anybody

 

[9fingers]

This machine possibly has a 1.5 -2hp motor? At this power it is marginal whether a 13 amp supply is genuinely suitable. Clearly it benefits a vendor to say that it can run on 13 amp plug. For every user who has a problem, there will be another who has no difficulties

Some of the problems can be with your installation or the voltage from your supplier that you can do little about.

Best course of action is to install a 16amp radial circuit and use a type C circuit breaker and you should have no further such problems.

Bob

 

[Gordon T]

Thank you Bob, the motor is 2 horse power......it is strange because my lathe is 3 horse power and works perfectly even with other machines, lights heaters etc running at the same time. Strange Recordpower advertising the bandsaw will work on 13amp when it seems unable to!!

 

[9fingers]

What i was trying to say was that there WILL be some supplies that it will start on but clearly not yours.
This is not necessarily a fault of your installation.
A lathe is a lot easier to start than a bandsaw. It is the combination of startup current AND the duration that blows fuses. Type C breakers are capable of taking overload currents for longer hence their use on motor circuits.

HTH

Bob

 

[Stoday]

If you have an extension lead, try plugging it between the motor and the mains socket. That will introduce a little resistance that will reduce the starting transient somewhat. If it dosn't work, it will have cost you nothing.

 

[OLD]

Friction is a factor try turning the wheels by hand and may be reduce tension or increase guide clearance checking blade runs straight true and is turning freely .The motor needs to get moving quick and generate some back emf to reduce current requirement.

 

[Digit]

Years ago Gordon there was a programme on the good old fashioned wireless entitled 'Round the Horn' with such titbits as 'Are Exits on the Way Out?', or 'how much is a fourpenny loaf?'
It's the same with Horsepower, one manufacture's HP is not the same as anothers.
The only reliable figure these days is the Full Load Current.
Horsepower now-a-days is a salesman's figure.

Roy.

 

[Gordon T]

Hello all, I had an electrician here today, my supply is 240 v and on startup only dropped to 239, blew the plug fuse immediately, think I have a faulty machine, ( workshop has its own 30 amp supply from house via a 4mm underground sheathed cable , and earth shows a 4 which I believe is good ).
Record are taking it back to test it at their place, I am not holding my breath.

 

[9fingers]

Hi Gordon,
Your installation sounds like it is solid. It does rather sound like a machine problem - rare if it is a new one. Hope you get it sorted in a reasonable time.

Bob

 

[Digit]

I dunno Bob, it runs without the belt remember, but time will tell.

Roy.

 

[JanneKi]

Will it start up, if you 1st rotate the wheels (give them a spin, so that they are on the "move" already) and then turn it on? That sometimes helps, but that's usually a sign that either the condensator is busted OR there are some more serious issues with the actual motor.

 

[Gordon T]

Hello all, today I plugged my extension lead into the kitchen ran it out to the workshop plugged in the new bandsaw and it worked every time I turned it on!!!!!!!!!
Then the electrician called again with his megga meter, checked my wiring, my sockets and fuse box and is baffled, can not find the problem, clearly the machine will work but not in my workshop. What the ****

 

[9fingers]

Whack a 16 amp socket in from a type C breaker and you will have no further problems.

Bob

 

[Gordon T]

Hi Bob, if I have a 16amp system fitted will the cables on the machine cope with the extra ampage, I know an amateur question, but better to ask than guess and make a bad job worse,
G

 

[9fingers]

The cable should be fine Gordon, the extra current is only during starting, and the cable is carrying that now.

I expect the flex is 1.5mm^2 which is rated at 15 amp continuous. If I were selecting a new cable I'd possibly use 2.5mm^2 but in this application I'd not bother to change whatever you have got fitted.

Bob

 

[Stoday]

Hello all, today I plugged my extension lead into the kitchen ran it out to the workshop plugged in the new bandsaw and it worked every time I turned it on!!!!!!!!!
Then the electrician called again with his megga meter, checked my wiring, my sockets and fuse box and is baffled, can not find the problem, clearly the machine will work but not in my workshop. What the ****

Now try plugging the extension lead into a socket in the workshop. I'd expect it to work OK.

 

[9fingers]

I had a visit from a UKW member today in order to check over a motor from a scheppach planer.

Out of interest I made some measurements on the starting current.

It was plated as 1.5kW and 9.5 amps running current. Using a peak hold ammeter, the peak starting current averaged over about 4 attempts was a whopping 24amps. This was with no load, just sitting on the bench! Furthermore it did not blow a 13amp fuse in the plug.

Bob

 

[Digit]

Based on some experiments I carried out years ago Bob I found that 13 Amp fuses would stand more than double their rating, briefly.
At between 26 and 30 amps some would survive for more than one second. There was an additional time factor that I think we are all aware of, the fuse may stand it once, repeat the current surge too soon and the fuse would then rupture at a lower rating.
I tend now to rely more on suitably rated MCBs.

Roy.

 

[9fingers]

Agreed Roy, an MCB offers better protection.
I was just running this motor up as a test using a SafeBlock which has an integral 13 amp fuse as well as a second one in its plug.
As it happened, the SafeBlock was plugged into a 4 way socket strip which would have has a third 13 amp fuse!

Bob

 

[Digit]

Makes me wonder what my SIP TS draws as it blew 13 Ampers as when it felt like it.

Roy.