Ready-to-Run (RTR) SSR DC Speaker Protection and Delay GB

[charliemb]

I think I've got it. Break loose, populate, and mount the breakout board near the secondary winding and wire the input side. Then, with reference to the Rev2 schematic, connect a twisted pair cable from Molex connector X2 on the breakout board to connector X1 on the SSR board. Pin 2 connects to pin 2, pin 1 to pin 1. Is this what you had in mind?


Thanks

 

[xrk971]

Preorder status update:
Thanks to s610adam, nautibuoy, baobei, and wirewiggler? Please add note to your preorder with your screen name when placing order in Etsy so I can track. Or correct the list if I have it wrong.

xrk971 / 76 units / USA
Monk55 / 2 units / USA *Pre-order Placed*
Nautibuoy / 2 units / UK *Pre-order Placed*
pinkfloyd4ever / 2 units / USA
MvonB / 2 Units / Germany *Pre-order placed*
Legis31 / 2 units / USA *Pre-order Placed*
mbrennwa / 4 units / Switzerland *Pre-order Placed*
s610adam / 2 units / USA *Pre-order Placed*
Baobei / 2 units / UK *Pre-order Placed*
meanie / 4 units / SG
wirewiggler / 2 units / USA *Pre-order Placed*(?)

 

[xrk971]

I think I've got it. Break loose, populate, and mount the breakout board near the secondary winding and wire the input side. Then, with reference to the Rev2 schematic, connect a twisted pair cable from Molex connector X2 on the breakout board to connector X1 on the SSR board. Pin 2 connects to pin 2, pin 1 to pin 1. Is this what you had in mind?


Thanks

Yes, you have it correct.

 

[charliemb]

The add on board provides the open collector signal to shutdown the SSR even if it’s powered by the main (high capacitance) PSU rail. You are probably correct about the regulator exceeding the thermal limit for a high voltage rail. We should advise us of some sort of voltage dropper zener as you suggest for higher voltages. I’ll let Jhofland reply in more detail though. I have used it with 53v rail and it has been ok. Just warm not not. The board probably has an effective area larger than 1 in square.

Interestingly, using a zener to cool down the regulator will have a secondary effect of shutting down the regulator earlier. This would disengage the speakers earlier and perhaps early enough to avoid a turn-off thump.
I, actually, wouldn't do it this way as I prefer the breakout board method you've provided. It's definitive.

Speaking of zeners, for a future Rev3 version, below is another definitive and easy way to provide a fast off for avoiding a turn-off thump. This zener is NOT in series with the regulator as above, rather it is in parallel.

Rather than tying the enable pin of the NCP781 directly to +ve, tie +ve to a jumper that normally shorts out two through-hole pads for a user-installable zener diode. You’d also provide a pull down resistor at the NCP781’s enable pin to ground, say 4.7k. The board ships with the jumper and resistor installed and no zener. Should the user decide to implement the fast off feature, they pull the jumper and install the appropriate zener.
The PCB ties the zener's cathode(+) pad to +ve and the zener's anode(-) pad to the pull-down resistor to ground. The enable pin is tied between the zener and the pull-down resistor.
The voltage value of the zener is user selected and installed according to the specific rail voltage of the amp and the droop allowed before the NCP781 disables itself.
For example, if the amp has 42v rails and the user chooses to allow for 7v of droop, the user pulls the jumper and installs a 35v zener.

Pulling the jumper could add turn-on delay to the existing 3 seconds. I imagine it should be minor.


A picture is worth 1000 words...

 

[xrk971]

I wasn’t thinking of the zener to make the shutdown faster. Just to address your concern of excess dissipation if rails are too high.

We found that a low capacitance power supply feeding the regulator was sufficient to shut down the SSR before turn off thump. This was discussed earlier as using half wave bridge and 22uF cap that feed power input. It would collapse in under 100milliseconds upon the PSU secondaries losing power.

 

[xrk971]

Happy New Year folks!

The preorder is almost completed and only Meanie is left. Thanks to everyone for placing the preorders so promptly.

GB gen2 preorder status update:

xrk971 / 76 units / USA
Monk55 / 2 units / USA *Pre-order Placed*
Nautibuoy / 2 units / UK *Pre-order Placed*
pinkfloyd4ever / 2 units / USA *Pre-order Placed*
MvonB / 2 Units / Germany *Pre-order placed*
Legis31 / 2 units / USA *Pre-order Placed*
mbrennwa / 4 units / Switzerland *Pre-order Placed*
s610adam / 2 units / USA *Pre-order Placed*
Baobei / 2 units / UK *Pre-order Placed*
meanie / 4 units / SG
wirewiggler / 2 units / USA *Pre-order Placed*

 

[Monk55]

HNY

 

[thompsontechs]

xrk971 / 76 units / USA
Monk55 / 2 units / USA *Pre-order Placed*
Nautibuoy / 2 units / UK *Pre-order Placed*
pinkfloyd4ever / 2 units / USA *Pre-order Placed*
MvonB / 2 Units / Germany *Pre-order placed*
Legis31 / 2 units / USA *Pre-order Placed*
mbrennwa / 4 units / Switzerland *Pre-order Placed*
s610adam / 2 units / USA *Pre-order Placed*
Baobei / 2 units / UK *Pre-order Placed*
meanie / 4 units / SG
wirewiggler / 2 units / USA *Pre-order Placed*
thompsontechs/2/USA *Paid

 

[thompsontechs]

How long does it take to engage and how much DC does it have to sense to do so? I glanced through, but didn't catch it if it's there...

JT

 

[xrk971]

Thanks Thompsontech!

From Post 1:

Specifications:
- PCB size is 70mm x 35mm and the M3 screw mounting holes are 62mm x ~26.5mm
- Requires > +19vdc power supply (can use +ve rail from your amp) and internally regulated to 15v
- Fully tested for 100w rms continuous load into 8ohms (MOSFETs are rated for up to 154w into 8ohms)
- Fully tested to handle 48vdc continuous DC fault
- 3 second turn on delay
- For a 48vdc fault, turn-off time is 25 milliseconds, 1.5v thrreshold

Preorder status update:

xrk971 / 76 units / USA
Monk55 / 2 units / USA *Pre-order Placed*
Nautibuoy / 2 units / UK *Pre-order Placed*
pinkfloyd4ever / 2 units / USA *Pre-order Placed*
MvonB / 2 Units / Germany *Pre-order placed*
Legis31 / 2 units / USA *Pre-order Placed*
mbrennwa / 4 units / Switzerland *Pre-order Placed*
s610adam / 2 units / USA *Pre-order Placed*
Baobei / 2 units / UK *Pre-order Placed*
meanie / 4 units / SG
wirewiggler / 2 units / USA *Pre-order Placed*
Thompsontech / 2 units / USA *Pre-order Placed*

 

[thompsontechs]

Had to try something else X that nasty pop with the other on my cheapo speakers scared the crap out of me... Noway, I was going to turn them loose on10k speakers,

See above questions if ya would....

 

[xrk971]

I think our posts crossed. Please see edit on earlier post. It’s quick in tens of milliseconds and 1.5v is threshold.

What are the $10k speakers? Wharfedales?

 

[thompsontechs]

PAP Horn 1 and Harbeth SHL5 Plus AN also have a pair of highly modded Tektons in the lab.

Sweet on clamp time and voltage.

 

[Freiheit]

Hi just discovered this group buy. May I join? Added myself to the list. Happy new year!

xrk971 / 76 units / USA
Monk55 / 2 units / USA *Pre-order Placed*
Nautibuoy / 2 units / UK *Pre-order Placed*
pinkfloyd4ever / 2 units / USA *Pre-order Placed*
MvonB / 2 Units / Germany *Pre-order placed*
Legis31 / 2 units / USA *Pre-order Placed*
mbrennwa / 4 units / Switzerland *Pre-order Placed*
s610adam / 2 units / USA *Pre-order Placed*
Baobei / 2 units / UK *Pre-order Placed*
meanie / 4 units / SG
wirewiggler / 2 units / USA *Pre-order Placed*
Thompsontech / 2 units / USA *Pre-order Placed*
Freiheit / 2 units / Germany

 

[thompsontechs]

Freiheit, order them from the site here:

Put your diyaudio username in the comments section, so he knows who it was that ordered....

JT

 

[Freiheit]

Thank you, JT. Done!

 

[xrk971]

Thanks Freheit!

xrk971 / 76 units / USA
Monk55 / 2 units / USA *Pre-order Placed*
Nautibuoy / 2 units / UK *Pre-order Placed*
pinkfloyd4ever / 2 units / USA *Pre-order Placed*
MvonB / 2 Units / Germany *Pre-order placed*
Legis31 / 2 units / USA *Pre-order Placed*
mbrennwa / 4 units / Switzerland *Pre-order Placed*
s610adam / 2 units / USA *Pre-order Placed*
Baobei / 2 units / UK *Pre-order Placed*
meanie / 4 units / SG
wirewiggler / 2 units / USA *Pre-order Placed*
Thompsontech / 2 units / USA *Pre-order Placed*
Freiheit / 2 units / Germany *Pre-order Placed*

 

[ricyuyc]

xrk971 / 76 units / USA
Monk55 / 2 units / USA *Pre-order Placed*
Nautibuoy / 2 units / UK *Pre-order Placed*
pinkfloyd4ever / 2 units / USA *Pre-order Placed*
MvonB / 2 Units / Germany *Pre-order placed*
Legis31 / 2 units / USA *Pre-order Placed*
mbrennwa / 4 units / Switzerland *Pre-order Placed*
s610adam / 2 units / USA *Pre-order Placed*
Baobei / 2 units / UK *Pre-order Placed*
meanie / 4 units / SG
wirewiggler / 2 units / USA *Pre-order Placed*
Thompsontech / 2 units / USA *Pre-order Placed*
Freiheit / 2 units / Germany
ricyuyc / 2 units / Hong Kong *Pre-order Placed*

 

[thompsontechs]

When are you placing the order X?

JT

 

[xrk971]

Very soon, just waiting for funds to get consolidated to do the payment for the manufacturing.