How to recognise/transform a 110V Falcon PSU?

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mikro
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How to recognise/transform a 110V Falcon PSU?

Post by mikro » Sun Jun 24, 2018 11:54 am

I have two Falcon PSUs which have gone bad. One just making "tsk-tsk-tsk-tsk" sounds (and power LED blinking) and one which... ehm, had sort of exploded. I plan to recap one of them with Exxos' PSU capacitor kit.

The latter one came with a CT2B Falcon from Canada and I assume it's a 110V version? (the one on the right). Two questions:
IMG_20180624_123944-new.jpg
IMG_20180624_123944-new.jpg (101.76 KiB) Viewed 582 times
1. Is there a way to verify this is really a 110V one? From what I can see there's only one significant difference - the capacitor on 220V version says "400V, 33 uF" while the exploded one says "200V, 47 uF". That would make sense why it had exploded (230V > 200V) but I wanted to make sure (for instance the fuse says 250V on both).

2. If the above is true, can I transform this PSU into a 220V only by changing the capacitors from the kit by Exxos?

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Re: How to recognise/transform a 110V Falcon PSU?

Post by exxos » Sun Jun 24, 2018 12:11 pm

It would make sense 400V > 230VAV, 200V > 120VAC..

There are resistors swapped about or missing between the 2.. I never had a 120V one to image. So when I get home I will take a image of my 230V one..
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Re: How to recognise/transform a 110V Falcon PSU?

Post by Forgottenmyname » Sun Jun 24, 2018 12:22 pm

Correct me if i'm wrong but wouldn't the number of coils in the transformer be different?

I'd suspect you'd not get the correct voltages out of the 110V one with the correct capacitors due to the ratio of incoming / outgoing voltages across the transformer. The Caps, regs and smoothing circuit would be based upon the 110 - 12v, 5v etc conversion, which would be more like 220 - 24v across that transformer when 220 - 240v were applied to it?

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Re: How to recognise/transform a 110V Falcon PSU?

Post by exxos » Sun Jun 24, 2018 12:29 pm

Forgottenmyname wrote:
Sun Jun 24, 2018 12:22 pm
Correct me if i'm wrong but wouldn't the number of coils in the transformer be different?
Yes and no. They could be different, but such switchmodes are more dependent on "pulse power" on the core. If there was different turns ratio, the pulse would be double or half width to maintain the "power" in the core.

Only way to really know is measure both transformers inductance and resistance..
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Re: How to recognise/transform a 110V Falcon PSU?

Post by Forgottenmyname » Sun Jun 24, 2018 12:40 pm

Fair enough, never worked on switch mode but will have to Google it.

Thanks for the info.

mikro
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Re: How to recognise/transform a 110V Falcon PSU?

Post by mikro » Mon Jul 09, 2018 7:07 pm

Please excuse my technological ignorance but what's the conclusion here then? Is it possible just to 'exxos recap' the PSU (incl. the rectifier) and get nice 230V on output? (if not perhaps would be still nice to recap it & sell as a 110V one but AFAIK there's no recap kit for the US models?)

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Re: How to recognise/transform a 110V Falcon PSU?

Post by exxos » Mon Jul 09, 2018 10:04 pm

mikro wrote:
Mon Jul 09, 2018 7:07 pm
Please excuse my technological ignorance but what's the conclusion here then? Is it possible just to 'exxos recap' the PSU (incl. the rectifier) and get nice 230V on output? (if not perhaps would be still nice to recap it & sell as a 110V one but AFAIK there's no recap kit for the US models?)
Post a 110V one in the falcon motherboard images section.. maybe we can figure it out...

I assume my re-cap kits will work on both , but I never seen or had a 110V one here. AFAIK there are some resistor differences between the 2.. but thats all I know so far.

viewforum.php?f=59
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Re: How to recognise/transform a 110V Falcon PSU?

Post by mikro » Tue Jul 10, 2018 8:32 am

exxos wrote:
Mon Jul 09, 2018 10:04 pm
Post a 110V one in the falcon motherboard images section.. maybe we can figure it out...

I assume my re-cap kits will work on both , but I never seen or had a 110V one here. AFAIK there are some resistor differences between the 2.. but thats all I know so far.

viewforum.php?f=59
Done: viewtopic.php?f=59&t=961

Too bad I didn't focus on this more when sending you the other PSU, could have send it both to you. Anyway, I still can if we don't figure something out.

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Re: How to recognise/transform a 110V Falcon PSU?

Post by exxos » Tue Jul 10, 2018 1:33 pm

mikro wrote:
Tue Jul 10, 2018 8:32 am
Done: viewtopic.php?f=59&t=961

Too bad I didn't focus on this more when sending you the other PSU, could have send it both to you. Anyway, I still can if we don't figure something out.
Most likely other than the capacitor which is blown, it is likely blown the 2 IC's as well. Possible it could have blown the main drive transistors well. Though I would suspect as mostly it is capacitors and resistors, that should be fixable relatively easily by changing those parts.
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