77 replies to this topic

[turbobob]

Wires on a pcb? Yeah please post a picture. 

[ciderbooze]

Filter cap dumping back to mains side is my guess.it's not as simple as saying caps pass a.c.. they attenuate or pass based on the a.c. frequency applied. It will probably be on the small side and should be a safety cap (y1 but memory might be playing up on that)

Edited by ciderbooze, 05 November 2013 - 09:12 PM.

[slindborg]

Wires on a pcb? Yeah please post a picture. 

Bear in mind most 'consumer shite' pcbs are just cow p*ss boards wi wire links and crappy thru hole components

[turbobob]

I'm quite  aware of how capacitors pass alternating voltage and the formulas involved and whether they are part not a filter or not. . I want to see a picture of said circuit. 

[turbobob]

 

Wires on a pcb? Yeah please post a picture. 

Bear in mind most 'consumer shite' pcbs are just cow p*ss boards wi wire links and crappy thru hole components

 

Feck me, we  build many many circuits a year. We do some hideous shite with dremels and wires and this is government approved.  But it's what the customer wants. So we do it. I may not agree with it

[vocky]

photobucket is down at the moment, so ....

 

[attachment=25150:SAM_3365.JPG]

 

the circle on the left is the 0v cable and the capacitor join (underneath the pcb)

 

the circle on the right shows the neutral cable and the wire going to the capacitor (joined underneath the pcb)

Edited by vocky, 05 November 2013 - 09:21 PM.

[turbobob]

Need to see the underside of the pcb also.  But it looks like the Ac is going through the first transformer 

[vocky]

Need to see the underside of the pcb also.  But it looks like the Ac is going through the first transformer 

the centre transformer is the isolator, the only other thing which joins the two sides of the pcb is the brown wire, underneath the AC / DC circuits are quite seperate

[slindborg]

Mmm that's well worth the price you paid

[turbobob]

Like I say without full pictures and preferably schematics it's difficult to say. But the mains wiring is right next to a transformer. Which would suggest the first transformer is isolation. . The brown strap on wire looks like an afterthought. The 8 pin ic near the top has discoloured the pcb slightly which suggests most power going through that part as it has got hot.

[turbobob]

Mmm that's well worth the price you paid

It does look a bit gash. The pcb is fr2 which is paper based

[slindborg]

I'd not say it was an after thought..... Come on you work more in the industry than I have and this is a surprise to you?

[ciderbooze]

Sorry turbo I am not aware of you background I was responding to your general statement this caps pass a.c. You must be blessed with working with decently built stuff as there are many examples of shite build quality that finds its way into production I see nothing out the ordinary in vockys pic. Tons of Chinese Crap churned out just like that.

[turbobob]

I'd not say it was an after thought..... Come on you work more in the industry than I have and this is a surprise to you?

 Not at all. It's a cheap design. Ffs. No one uses fr2 these days. I suspect that there was a cheap design and a 'mod'  was introduced. We have to do it quite often. Not our choice but through our customers request. I cringe at a lot of stuff we have to do. Like I say some of it is government approved..... 

[turbobob]

Sorry turbo I am not aware of you background I was responding to your general statement this caps pass a.c. You must be blessed with working with decently built stuff as there are many examples of shite build quality that finds its way into production I see nothing out the ordinary in vockys pic. Tons of Chinese Crap churned out just like that.

No problem

. 

I'm the qa and engineering manager for an electronics assembly company so I see high volume low value (eg £2 per pcb) all the way through to low volume high value stuff (eg £10k per pcb assembly). 

[Goosenka]

Has your hair turned out the way it is as a result of working with too much electricity Bob?

[Zoobeef]

I wish I knew more about this magic you people talk of

[Goosenka]

I wish I knew more about this magic you people talk of

What?? You seem to know everything Zoobeefage. Next course perhaps?

[GeorgeBC]

I wish I knew more about this magic you people talk of

Must be the first person ever to wish he was more like turboknob

[Zoobeef]

I wish I knew more about this magic you people talk of

What?? You seem to know everything Zoobeefage. Next course perhaps?

Well I'd consider myself not too bad at 12/24v DC vehicle systems and am able to set up, run and maintain generators to run whole bases and have rewired a house but there's still a lot to learn. Yes I'd like to train to be an electrician but think even that wont cover in the detailed knowledge of slindborg and turbobob etc.