my stax 717 blows the fuses at the input of the transformer 220v 1.5 fast blow - do i need test slow blow or fast blow 30A fuse?

[Omega_ELS]

Good day, dear gentlemens.

my stax 717 blows the fuses at the input of the transformer 220v 1.5 fast blow.

do i need test slow blow or fast blow 30A fuse?

If I decide to install 30A, is there a safer way to do it, like connect it through an incandescent lamp or something like that?

What is the normal resistance of the windings of this transformer in 717 should be at the input on the socket?

 

When I bought it, it had a 220-volt, 1.5-amp fast-blow fuse installed.

But according to the schematic, I need a 220-volt, 1.5-amp slow-blow fuse.
But I can't find one anywhere yet.

 

By the way, I measured the transformer resistance on the 220V plug that plugs into the outlet—it's only 12.7 ohms.
I'm not sure that's how it should be...

 

 

any advice is welcome

Edited 13 hours ago by Omega_ELS

[kevin gilmore]

are you sure of the jumpers for the voltage you are using.  if jumpered on 100 or 120v and you put 220 in it, fuse will blow instantly.

but you do need a slow blow fuse.

[Omega_ELS]

Just now, kevin gilmore said:

are you sure of the jumpers for the voltage you are using.  if jumpered on 100 or 120v and you put 220 in it, fuse will blow instantly.

but you do need a slow blow fuse.

Hi Kevin
Thank you for your interest in this topic.

Yes, I set the jumpers to positions 2 and 5.
When I bought it, it had a 220V 1.5A fast-blow fuse.
But after a few months, it failed and blew.

Today, I bought the same one, 1.5A, and even 2A – they both blew instantly.

Since I can't find a slow-blow fuse, I bought several fast-blow fuses, 10-20-30A, and I'm thinking of trying them.

But I'm afraid to do that because I'm not sure it's just the fuse....

By the way, I measured the transformer resistance on the 220V plug that plugs into the outlet—it's only 12.7 ohms.
I'm not sure that's how it should be...

[spritzer]

If the fuses are blowing, then something is wrong somewhere.  Never use fast blow fuses, let alone 30A.  If the fuse manages to hold and something is shorted, do you want to dump 2.4kW into the amp?  No...  

[kevin gilmore]

you do not have the jumpers in the right position for the voltage you need.

the voltage rating on the fuse is meaningless.

[Omega_ELS]

11 hours ago, spritzer said:

If the fuses are blowing, then something is wrong somewhere.  Never use fast blow fuses, let alone 30A.  If the fuse manages to hold and something is shorted, do you want to dump 2.4kW into the amp?  No...  

Hi Birgir
Thank you for your interest in this topic.
I just can't find a suitable slow-blow fuse =(

Its dimensions should be 6x30 or 6.2x32 or something like that, it should be rated for 250v and 1.5a and be a slow blow..

So I thought I could use a higher-amperage fast-blow fuse for timing tests...

 

38 minutes ago, kevin gilmore said:

you do not have the jumpers in the right position for the voltage you need.

the voltage rating on the fuse is meaningless.

 

Hi Kevin, thanks for your comment.

Well in my 220-volt network, the voltage sometimes rises to 230...
So I thought it would be a good idea to put jumpers on 2 and 5...

instead of 3 and 5....

just to have some reserve...
It seemed to me that it's better to have a reserve of -10 volts

than +10..

As far as I understand, the power supply here is unregulated

and exceeding the input voltage is a bad idea...