You can have a look at our line of SMPS:
www.coldamp.com
I would recommend SPS80HV, with that product you can get above 1KW continuous. If you don't find what you need we can create custom voltages for you.
www.coldamp.com
I would recommend SPS80HV, with that product you can get above 1KW continuous. If you don't find what you need we can create custom voltages for you.
Of course also hypex might be a worth a look.
SMPS1200
The beauty of the smps1200 is the synchronous rectification, which improves efficacy , and even more valuable prevents all issues that are often discussed regarding supply rail pumping of class D half bridges.
IMHO also nice.
- An auxiliary supply: +/-12V
- A floating auxiliary supply for the lower gate drive and the bootstrap supply.
I do have one on my desk and different from multiple other brands the hypex smps passed my private visual safety check regarding creepages and clearances. Well - for some reason I did not unwind the transformer, but I did not see obvious short comings in the visible areas of the smps construction. So I got trust on the transformer as well.
Don't take me as a certification institute.
It's just that I do have a personal opinion (EN60065 minded) what I want to use in my living room, because sueing after death is not a fortunate option.
SMPS1200
The beauty of the smps1200 is the synchronous rectification, which improves efficacy , and even more valuable prevents all issues that are often discussed regarding supply rail pumping of class D half bridges.
IMHO also nice.
- An auxiliary supply: +/-12V
- A floating auxiliary supply for the lower gate drive and the bootstrap supply.
I do have one on my desk and different from multiple other brands the hypex smps passed my private visual safety check regarding creepages and clearances. Well - for some reason I did not unwind the transformer, but I did not see obvious short comings in the visible areas of the smps construction. So I got trust on the transformer as well.
Don't take me as a certification institute.
It's just that I do have a personal opinion (EN60065 minded) what I want to use in my living room, because sueing after death is not a fortunate option.
Johnson, you are bringing me into trouble!
....I am going to make friends now...
Con:
Look at the pic of the a1000smps.
When you look at the design you will find the power Mos (primary) and the output diodes (secondary) on the same heat sink. The way of isolation of the diodes lets expect almost no creepage vs the heat sink, while the way of isolation of the MosFets lets expect approx. 1.5mm creepage. So on the heat sink primary vs secondary have approx 1.5mm creepage. In Europe safety standards would need something between 6mm-8mm, depending on some details and interpretation of the EN60065. Another place of short creepage is on the left hand side of the black caps (primary) and the resistor (secondary) next to it.
Cold:
Again look to the pictures.
Well, they have special isolation for the MosFets, but distances between PCB vs. heat sink and between leads vs. heat sink appear pretty small.
Also the fact that you can see the copper of the windings in the transformer instead of margin tape does not generate trust to me.
For my living room both are out of the race.
Cold and Con: Feel free to tell me bad ...
P.S.
In fact in the meanwhile I am convinced that lots of the DIY SMPS stuff has short comings in safety. So there is no clue in avoiding Cold or Con while buying something else which might be worse!
There is almost no control from authorities regarding these safety topics.
It is up to us DIYers to check carefully what we have bought.
If unable to check, stay with products which have been approved by a valid certification institute and shop at a place where you can easily approach the vendor.
....I am going to make friends now...
Con:
Look at the pic of the a1000smps.
When you look at the design you will find the power Mos (primary) and the output diodes (secondary) on the same heat sink. The way of isolation of the diodes lets expect almost no creepage vs the heat sink, while the way of isolation of the MosFets lets expect approx. 1.5mm creepage. So on the heat sink primary vs secondary have approx 1.5mm creepage. In Europe safety standards would need something between 6mm-8mm, depending on some details and interpretation of the EN60065. Another place of short creepage is on the left hand side of the black caps (primary) and the resistor (secondary) next to it.
Cold:
Again look to the pictures.
Well, they have special isolation for the MosFets, but distances between PCB vs. heat sink and between leads vs. heat sink appear pretty small.
Also the fact that you can see the copper of the windings in the transformer instead of margin tape does not generate trust to me.
For my living room both are out of the race.
Cold and Con: Feel free to tell me bad ...
P.S.
In fact in the meanwhile I am convinced that lots of the DIY SMPS stuff has short comings in safety. So there is no clue in avoiding Cold or Con while buying something else which might be worse!
There is almost no control from authorities regarding these safety topics.
It is up to us DIYers to check carefully what we have bought.
If unable to check, stay with products which have been approved by a valid certification institute and shop at a place where you can easily approach the vendor.
Mmm, ChocoHolic, you only "make friends" if you don't expose the facts fairly and with real data.
Let me correct you in that "Cold" PSUs (you can say the complete name, please, we'll continue being friends) DO meet all the EN60065 safety regulations.
In fact our PSUs have more creepage and clearance than really required, and we even use TIW (triple insulated wire) for the transformer primary windings, a kind that is very expensive and usually reserved to medical specified units. In any case our units are Class-I devices requiring Earth connection.
It is not casual then that some big companies are using our supplies with total confidence and passing certifications with no issues.
So you can be confident about the safety of our PSU units, of course.
Let me correct you in that "Cold" PSUs (you can say the complete name, please, we'll continue being friends) DO meet all the EN60065 safety regulations.
In fact our PSUs have more creepage and clearance than really required, and we even use TIW (triple insulated wire) for the transformer primary windings, a kind that is very expensive and usually reserved to medical specified units. In any case our units are Class-I devices requiring Earth connection.
It is not casual then that some big companies are using our supplies with total confidence and passing certifications with no issues.
So you can be confident about the safety of our PSU units, of course.
Hi Ssanmor,
glad to see you answering in a friendly and technical manner.
Protection class I and Tex-E (or similar triple insulated) wires...
I agree these wires would basically allow a transformer design with less or even without margin tape/spacers. Definitely not normal to use such wires for a big transformer in consumer applications. 'You rich???'
Class I devices - that's a key information.
Means your SMPS does not need to fullfil double/reinforced insulation, but basic insulation only. ...bringing down the required creepages by factor two vs. what I had anticipated. This could fit to the pictures.
Less demanding for the smps, but more demanding for the DIYer to fullfill the stringend requirements for all protective earth wirings.
Also more demanding for a proper system set up which does not suffer from earth loops - especially in distributed systems... (a desktop computer at one power outlet and the amp at another, the PS3 again somewhere else and a beamer... and may be even a radio with antenna plug ? ... pretty inconvenient to do audio in the class I world.., of course I always found a proper solution, but 
.. )
I have to apologize. I was automatically anticipating suitability for protection class II and furtheron would never have expected triple insulated wires
. Nevertheless, your smps is still remaining out of the race for my private living room projects, because I decided to do my DIY audio stuff in protection class II.
I guess Cristi will show up soon here, too.
Looking forward to get his feedback about their safety concept.
glad to see you answering in a friendly and technical manner.
Protection class I and Tex-E (or similar triple insulated) wires...
I agree these wires would basically allow a transformer design with less or even without margin tape/spacers. Definitely not normal to use such wires for a big transformer in consumer applications. 'You rich???'
Class I devices - that's a key information.
Means your SMPS does not need to fullfil double/reinforced insulation, but basic insulation only. ...bringing down the required creepages by factor two vs. what I had anticipated. This could fit to the pictures.
Less demanding for the smps, but more demanding for the DIYer to fullfill the stringend requirements for all protective earth wirings.
Also more demanding for a proper system set up which does not suffer from earth loops - especially in distributed systems... (a desktop computer at one power outlet and the amp at another, the PS3 again somewhere else and a beamer... and may be even a radio with antenna plug ?
... pretty inconvenient to do audio in the class I world.., of course I always found a proper solution, but .. )I have to apologize. I was automatically anticipating suitability for protection class II and furtheron would never have expected triple insulated wires
. Nevertheless, your smps is still remaining out of the race for my private living room projects, because I decided to do my DIY audio stuff in protection class II. I guess Cristi will show up soon here, too.
Looking forward to get his feedback about their safety concept.
Perhaps you don't have the "full picture" when you make this statements.
Creapage between the primary switches and heatsink is 6.4 mm, the footprint is offset about 3.5mm inwards and the legs are bended to allow placing insulating material all the way down to the pcb. moreover, the heatsink or heatslug is connected to protective earth, so if any short should ocure, this will be between the transistors and protective earth connection. I'm not the one who invented the common heatsink for power devices, primary switches and secondary diodes, it is extensively used in industry since the first designs of SMPS's.
Next, the distance between the cap and the resistor is about 5mm. the capacitor sleeve can withstand at 1000V RMS insulation test. and to create an arch, one would need a lightning strike, in which case the power supply isolation is the last thing to worry about. I have tested the unit for safety, and, surprisingly has passed, and i'm about to make a full certification, as soon as will be required by an OEM or wholesale customer, right now 12-15k usd, certification costs are planned for something else for the moment. and btw, i wonder how many commercial smps for audio have the certifications done, not just according....
I believe that the next step will be to criticize the SMPS800R because this has the low profile which the topic starter was looking for. Connexelectronic if isn't obvious from the picture, the smallest clearance and creapage between primary and secondary side is on the transformer, and measures 6.6mm. the transistors and diodes are completely isolated from the heatsink.
It couldn't be other way, you haven't been unrespectful, only that your judgement has been a bit hasty.
Anyway, Class-I (which is stated in all our datasheets with proper earthing recommendations) is not a problem in practice, I wouldn't expect 400W+ PSUs (SPS80 is even capable of >1200W continuous, >2000W music, despite the official rating) to be Class-II (double insulation), only small consumer applications. Any professional amplifier requires earth and we do support our customers so they wire and install the PSUs properly. Ground loops are usually not a problem if everything's done correctly.
I'm using 2 SMPS800R from Connex. Very happy with them.
I think I have read elsewhere that Class D Audio have recommended the SMPS800R ?
That amp has the balanced input? I'd be interested to hear how it works out for you as I'm looking for a balanced input amp for my subwoofers.
Hi Cristi,
I am finding 1.4mm between the drain plates of the primary switches and the screw.
Between primary caps and secondary resistors I am finding 1.3mm.
The insulating sleeves of e-caps are generally not considered as protective insulation.
It is not obvious whether the transformer offers 6.6mm creepage or not.
No, I am not planning to unwind and debug it - at least not for free.
I need my spare time to go on with my class D, that's why I decided to purchase a SMPS from stock instead of designing one.
If I have to design a smps, I am asking for money.
If I have to design a classD amp I go for it with a smile.
I am finding 1.4mm between the drain plates of the primary switches and the screw.
Between primary caps and secondary resistors I am finding 1.3mm.
The insulating sleeves of e-caps are generally not considered as protective insulation.
It is not obvious whether the transformer offers 6.6mm creepage or not.
No, I am not planning to unwind and debug it - at least not for free.
I need my spare time to go on with my class D, that's why I decided to purchase a SMPS from stock instead of designing one.
If I have to design a smps, I am asking for money.
If I have to design a classD amp I go for it with a smile.
Attachments
No, definitely screwing the power mosfets to a heatsink using metal screws is not a good idea, you will have small clearances as Chocoholic shows. Unless you use dedicated heatsink for each mosfet with proper clearances, although that's generally impractical for moderate to high power levels.
Hi,
I think it is right to look at the building, if they have complied with the standards for insulation. EN etc.
But I see that no one observes the behavior of the SMPS, given that supply power to an amplifier, if the output is clean (especially for class D), or if you have a good response time (if it is a regulated SMPS).
Regards
I think it is right to look at the building, if they have complied with the standards for insulation. EN etc.
But I see that no one observes the behavior of the SMPS, given that supply power to an amplifier, if the output is clean (especially for class D), or if you have a good response time (if it is a regulated SMPS).
Regards
Yes, but it is not a free surface, it's covered by an elastic insulator. Even if there were a very small gap, contamination is not likely to penetrate into there. So I wouldn't say it's really risky.
Indeed, it's not enough by itself, but as long as it's intact, it's perfectly enough against creepage, furthermore with the other insulator layers (resistor+air) they fulfill the double/enforced insulation requirement also. (IMHO!)
I bought this smps, because of regulation and multiple postings of Cristi, which made me trust in his expertise. And I still do, even when I am not happy with that smps in particular.
I did not check for the regulation, because I decided not to use it.
And regarding regulation I must state that the hypex is not regulated.
When loaded it sags and shows pretty some 100Hz output ripple.
HF-ripple appears to be far less than the 100Hz ripple.
Thanks to sync rectifiers the 100Hz ripple is symmetrical on pos and neg rail also at unsymmetric load. And also it perfectly avoids supply rail pumping.
Regulated +/- 12V outputs are just done by 7805 and 7905, resulting in the known noise of multiple hundrets of nV/sqrt(Hz).
==> Not really something special, but a good fit for my planned amp.
Edit: Did I say 7805 and 7905? Rubbish. 7812 and 7912 of course.
In general I agree to AP2 that regulation behavior can be pretty important.
The regulation time constants (or even regulation overshoot/ringing) can easily happen to be in the audible frequency range. If such artifacts happen in that range + the sagging/overshoot/ringing is not really small, then it might become necessary to evaluate the audiophile suitability in detail.
I did not check for the regulation, because I decided not to use it.
And regarding regulation I must state that the hypex is not regulated.
When loaded it sags and shows pretty some 100Hz output ripple.
HF-ripple appears to be far less than the 100Hz ripple.
Thanks to sync rectifiers the 100Hz ripple is symmetrical on pos and neg rail also at unsymmetric load. And also it perfectly avoids supply rail pumping.
Regulated +/- 12V outputs are just done by 7805 and 7905, resulting in the known noise of multiple hundrets of nV/sqrt(Hz).
==> Not really something special, but a good fit for my planned amp.
Edit: Did I say 7805 and 7905? Rubbish. 7812 and 7912 of course.
In general I agree to AP2 that regulation behavior can be pretty important.
The regulation time constants (or even regulation overshoot/ringing) can easily happen to be in the audible frequency range. If such artifacts happen in that range + the sagging/overshoot/ringing is not really small, then it might become necessary to evaluate the audiophile suitability in detail.
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Well, real physics seem to be country depending in this regard.
When looking to UL world, then any kind of potting is accepted to reduce the required creepages (as long as the potting is flame retardant
)I am willing to agree that the compressed silicone isolation will do a similar good job.
When looking to Europe safety relevant pottings have to be vacuum pottings and the evaluation of potting is done by cutting the potted thing into thin slices. If any bulbs are found inside ==> rejection.
In fact I am not sure which philosophy is closer to reality.
If we look to really high voltages the european bubble panic appears well reasoned for me. If you have stacked dielectrica the electric field splits inverse to dieletric constant. Most pottings/plastic isolator with dielectric constants between 2-6. Means by far higher than air. Consequently inside enclosed air bubbles there will happen undesired high fields, which in turn could lead to partial discharges...
But if we look to our concerned mains voltages of 230V (or 120V) and multiple mm distances, then we are far away from such effects.
Hm.. Currents creeping on a surface (or betweenface
), between two isolators closely pressed together? Anybody out there looking for a Phd topic ?At this point I am definitely not on your side.
Neither the insulating sleeve of the e-caps, nor the resistor coating is considered as safety relevant insulation.
...can't get out of my German skin...
Plastic / Vinyl screws would also not help much here.
Creepage would increase just by the thickness of the insulation washer. The trouble starts as soon as you have a hole/interruption in the washer close to the drain plate or any other conductive part of the MosFet.
And looking to the insulation washer:
For basic insulation there is no requirement for the thickness.
But for double/reinforced insulation the EN60065 requires a minimum material thickness of 0.4mm. Ohps,...did I check the hypex design for this? No, I didn't .
May be - I'd better stop to check what I buy and start believing instead.
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