Help needed to identify a part

[jctilingservices]

Hi guys, a bit more help needed please, i asked for help lastnight regarding my mothers sterling 10 alarm. So after recievi g some advice, this morning i went and bought some fuses and a new battery, connected the battery and the display panel illuminated (great, just what i wanted) put main fuse in and display went off, blew the new main fuse ( 20 mm quick blow) changed the fuse again but nothing on display, checked fuse and yep, that had blown again. Tried another fuse, this time i noticed a spark which looks like it came from the part i will post a pic of. Question is, can someone tell me what this part is called so i know what to look for online, also i noticed slight burning on this, so could thid be the cause of all my trouble?

 

[stem]

It's a transformer. It probably transforms the 230V mains voltage to something suitable for electronic circuits, something like 12V.

A competent individual with a suitable test meter would be able to test it for you. If the fuse that is blowing is supplying the primary side (230V) of the transformer then the winding's are likely shorting out inside.

 

[jctilingservices]

It's a transformer. It reduces 230V mains voltage to something suitable for electronic circuits, probably about 12V.

A competent individual with a suitable test meter would be able to test it for you. If the fuse that is blowing is supplying the primary side (230V) of the transformer then the winding's are likely shorting out inside.

If that is blown or shorting out or whatever, would that cause the main fuse to blow?

 

[stem]

If the windings impede the flow of current flow between live and neutral. They are made from wire that insulated with varnish that is known to deteriorate and breakdown, due to age or overheating. When this happens the electricity will take the easiest route and instead of passing through the entire circuit, it will take the easiest path through the shortcut where the wires are touching. This is known as a short circuit. Because of the short circuit, the current has an easier path to flow through and so the current flow increases to the point of blowing the fuse.

If the fuse that is blowing is connected to the secondary side of the transformer rather than the mains side, then it may be that the alarm circuit board is at fault and drawing too much current causing the fuse to blow. Although if it works under battery power then it is probably OK.

Testing the transformer in isolation is the only way to be sure.

 

[jctilingservices]

If the windings impede the flow of current flow between live and neutral. They are made from wire that insulated with varnish that is known to deteriorate and breakdown, due to age or overheating. When this happens the electricity will take the easiest route and instead of passing through the entire circuit, it will take the easiest path through the shortcut where the wires are touching. This is known as a short circuit. Because of the short circuit, the current has an easier path to flow through and so the current flow increases to the point of blowing the fuse.

If the fuse that is blowing is connected to the secondary side of the transformer rather than the mains side, then it may be that the alarm circuit board is at fault and drawing too much current causing the fuse to blow. Although if it works under battery power then it is probably OK.

Testing the transformer in isolation is the only way to be sure.

Thanks for the reply
I have wires coming from fuse box ( consumer unit ) into a chocky block inside alarm box, ( this wire is always live even when inline fuse has blown, unless I pull fuse from consumer unit, the wires from transformer go into the other side of the chocky block, when I put the fuse into the carrier and push it in, the fuse pops, I still have power going into chocky block, but nothing at other end ( wires to transformer ) , I did notice a flash from the transformer and what looks like burning on the plastic around windings. will attach 2 pics and hopefully it might be easier for you to understand what I am trying to explain ( rather badly lol )

 

[stem]

It's the fuse to the transformer that is blowing, so looks like the transformed is the problem then. Especially if you have seen it 'flash'.

What you are thinking is burning, looks more like varnish / lacquer to me, but still could indicate overheating.

 

[Keithmac]

Looks like transformer has failed internally (as said above).

You need to try and find a suitable replacement, correct output voltage.

 

[jctilingservices]

Looks like the transformer is the problem then.

Sorry to be a pest, but is there anyway I can find out what sort of transformer I need, I know its 240 but dropping down to what, the label only gives me this info Amc RTFR030
9902-14457-1VMW

I have tried googling these numbers but nothing comes up except for coil springs for cars lol

 

[sparkymarka]

17v ac ...does it blow the fuse with the white and orange removed from the alarm pcb ?

 

[jctilingservices]

17v ac ...does it blow the fuse with the white and orange removed from the alarm pcb ?

Never tried that to be honest with you, even if it is the transformer at fault I cannot locate one anywhere lol, do you think I should put it all back together again except for connecting the orange and white, then put the fuse in and see if it still blows ? unfortunately I wont be able to do this until tomorrow when I am back over my mothers house. I am assuming if the fuse blows then, it is the transformer but if not, the fault lies somewhere else ? The alarm system had not actually been set for approx. 1 year, but ( according to my elderly mother )yesterday morning it just went off blaring, without even being armed, it rang for about 4-5 mins, putting the code in done nothing, then its suddenly stopped. when she told me yesterday, I went to reset the alarm but the display panel in key pad was not illuminated, no power at all there, that's when I started checking for fuses etc

 

[sparkymarka]

First step try the transformer with no load , if it blows the fuse then transformer ....I may have one ....if fuse ok and you have replaced the battery then it looks like it's a pcb fault ....time to bin it !

 

[jctilingservices]

First step try the transformer with no load , if it blows the fuse then transformer ....I may have one ....if fuse ok and you have replaced the battery then it looks like it's a pcb fault ....time to bin it !

when you say try the transformer with no load, what exactly do you mean, sorry if I sound a bit stupid, but I assume you want me to reconnect everything, then do what, before I turn the power on at the consumer unit ?

 

[sparkymarka]

Not connected to the alarm panel ! Just make sure the orange and white wires are not touching each other !

 

[jctilingservices]

so if I understand you correctly, connect everything up as it should be, except for the orange and white to the pcb, but keep those separated, then turn on at consumer unit ?
thanks for all your time and effort explaining things for me, it really is appreciated

 

[sparkymarka]

Yes if the fuse blows it's the transformer