Power Supply Soft Start Board (V3)

Thanks for your post astromo .
I did read through those posts and links; but hobby wise at this stage I'm pretty much just a "parts changer" as they say.


Is a SMPS an option to power the Soft Start board ?


If you're a "parts changer" then it sounds like a ready made power supply would be more appropriate for you. To reiterate, this board is powered directly from the AC mains and is relevant to a transformer of a size of your choosing (subject to the guidance previously referred to) that is located downstream of the board.


If you opt for an SMPS, then inrush should be effectively dealt with and this board would be unnecessary (happy to be corrected by those with more knowledge). That's one of the reasons I'd expect that an SMPS PSU philosophy was chosen by Nelson Pass for the ACA. It avoids a lot of issues there by making it simple and easy AND because it supplies 19/24 VDC, the safety concerns of an AC mains is largely designed out.


I'm not sure you've got the fundamentals of this piece of kit bedded down (not that I think I have totally myself but I'm sure I'll give it another read or two before I do the final wire up). The write up in the guide that I linked to above provides a well reasoned and explained narrative. Very helpful and worthwhile.
 
this board is powered directly from the AC mains

Okay , I understand now astromo . Can't put the soft start board after the amplifier .
Initially when I read ( i.e. googled ) about speaker protection for my high efficiency full range speakers I was thinking of using a fuse. Then search results said fuses are used for tweeters .
So that's when the diyaudio store page with the soft start pcb appeared in my search results . I thought it might be an option.
 
No worries.

You were sent to the right place on the store. The thing is that, that one page covers two separate boards.

One for AC in-rush, i.e. soft start, and the other for speaker protection.

You've simply picked the wrong thread.

Take a closer look and it should self reveal.

:cheers:
 
You were sent to the right place on the store. The thing is that, that one page covers two separate boards.

One for AC in-rush, i.e. soft start, and the other for speaker protection.

You've simply picked the wrong thread.

Take a closer look and it should self reveal.

Many thanks astromo, and apologies to the moderator
I have vision issues using a 9 inch tablet and type font size 1 with tri-focals..... Well , that and a need to read more carefully . :D
My Windows machine retired itself and the family are usually streaming movies on my Mac.

I needed to scroll down the screen page all the way , I was focusing on the Ver 1 2 and 3 links .
On the proper speaker protection circuit thread a poster lists a transformer part number at Mouser for the PCB on the last page.
 
Apologies if this is covered elsewhere but I can't find anything.
What are the requirements for a mains power switch with the PS soft start board?
I will have 2 x 300VA toroids on a ESP P101 amp. I was hoping to use one of these S0933 DPDT Momentary LED Blue Solder Tail Pushbutton Switch - Altronics .
There is a 5A version at RS supplies that I could get.

Thanks,
kffern


The switch's current rating will come down to the current that you're expecting the load that's being driven to draw, won't it? What fuse rating are you working to? I'd think you'd want to be getting a reasonable match and I'd suggest that you could use that point of detail as a guide.


Info from Rod Elliot explains matters with more authority and knowledge than I could ever offer:
Linear Power Supply Design


To avoid blowing the switch's LED ring, you might want to look at how your PSU voltage lines up with the DC voltage limits for the switch. You might need to factor in a resistor to drop some volts out of the circuit.
 
The switch's current rating will come down to the current that you're expecting the load that's being driven to draw, won't it? What fuse rating are you working to? I'd think you'd want to be getting a reasonable match and I'd suggest that you could use that point of detail as a guide.
Thanks. I planned on using a 6A slow blow fuse. I thought the board might allow for a lower rated switch but I guess I was wrong. I have a pre-made 10A relay board I could use which requires a 5VDC supply. Its just that it is hard to find a nice looking switch for the front panel that is good for 8 to 10A. Re-reading ESP P39 information it seems that it does have facility for a low voltage switch relay but I didn't see it in the picture.

To avoid blowing the switch's LED ring, you might want to look at how your PSU voltage lines up with the DC voltage limits for the switch. You might need to factor in a resistor to drop some volts out of the circuit.
Thanks..

Kffern
 
My soft start boards arrived this week so I am just about to order the parts from the BOM as the first stage in an Aleph J build. Could someone please confirm that the parts on the BOM are all suitable for use at 240v? This is my first DIY electronics project (I've built lots of speakers over the years) and as this bit connects directly to the mains I thought I'd better check!
 
My soft start boards arrived this week so I am just about to order the parts from the BOM as the first stage in an Aleph J build. Could someone please confirm that the parts on the BOM are all suitable for use at 240v? This is my first DIY electronics project (I've built lots of speakers over the years) and as this bit connects directly to the mains I thought I'd better check!

I've built one for an Aleph J on 240VAC mains. No problem. I'll check what I ordered against the BOM and let you know of any variances. I don't recall anything significant.
 
Just ordered a couple of these boards on the Black Friday sale. I plan to use an external Z-wave appliance module in place of the Power switch. In this case I think that C1 could be eliminated. These modules are rated for 15 amp motor loads so I am assuming they have some form of internal protection. There are a variety of remotely controlled switches available these days that can be integrated into home control applications.
 
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Mains controlled by switch on chassis

Hi folks: I’ve tried to filter this out from all the posts but I’m still not certain. If my (120vac) mains feed is already controlled by an on/off switch on the chassis, do I run the output of the mains switch directly to SW2 on the board and skip anything to do with both Live/SW1 & C1? I’m using v3.0 soft start PCB.

Thanks,

Pete
:)
 
Hi folks: I’ve tried to filter this out from all the posts but I’m still not certain. If my (120vac) mains feed is already controlled by an on/off switch on the chassis, do I run the output of the mains switch directly to SW2 on the board and skip anything to do with both Live/SW1 & C1? I’m using v3.0 soft start PCB.

Thanks,

Pete
:)

I asked this exact same question but never got a reply so just went ahead and used SW2 and Neutral and it seems to work just fine for me!