Quote
Kp, for single 24V SMPS300R, not RE is suitable, SMPS300RE has only dual output voltage, +-xx V. If the required current is max. 4A, the SMPS200QR can be used too. it is the smallest size power supply with output power >200W for audio applications or ~ 100W continuous. If only one rail is needed, then the diodes from the negative output can be reversed and both positive an negative output can be paralleled to increase the output current, or to allow the diodes to work at half current.
Hi Cristi ,
Between the smps 200R and 300R , from a measurement point of view, which one measures better if used within the ampere range ?
thanks
kp93300
Kp, for single 24V SMPS300R, not RE is suitable, SMPS300RE has only dual output voltage, +-xx V. If the required current is max. 4A, the SMPS200QR can be used too. it is the smallest size power supply with output power >200W for audio applications or ~ 100W continuous. If only one rail is needed, then the diodes from the negative output can be reversed and both positive an negative output can be paralleled to increase the output current, or to allow the diodes to work at half current.
Hi Cristi ,
Between the smps 200R and 300R , from a measurement point of view, which one measures better if used within the ampere range ?
thanks
kp93300
Short circuited my smps500R
Hi Cristi,
I have bought a pair of +/- 50 Volt smps500R at Audiophonics (France).
When I received it measured +/- 49 Volt.
During testing the output cables touched a metal surface... sparks
Directly after the incident I inspected the board with a magnifier glass and could not find any burned parts. I powered it up again and the outputs measured +/- 98 Volts.
After 30 minutes I measured again to make sure my readings where accurate and now I have the normal reading again
I have checked again and put it back into my amp and now it is playing normally
What should I do??
Hi Cristi,
I have bought a pair of +/- 50 Volt smps500R at Audiophonics (France).
When I received it measured +/- 49 Volt.
During testing the output cables touched a metal surface... sparks
Directly after the incident I inspected the board with a magnifier glass and could not find any burned parts. I powered it up again and the outputs measured +/- 98 Volts.
After 30 minutes I measured again to make sure my readings where accurate and now I have the normal reading again
I have checked again and put it back into my amp and now it is playing normally
What should I do??
Hi Cristi,
I have bought a pair of +/- 50 Volt smps500R at Audiophonics (France).
When I received it measured +/- 49 Volt.
During testing the output cables touched a metal surface... sparks
Directly after the incident I inspected the board with a magnifier glass and could not find any burned parts. I powered it up again and the outputs measured +/- 98 Volts.
After 30 minutes I measured again to make sure my readings where accurate and now I have the normal reading again
I have checked again and put it back into my amp and now it is playing normally
What should I do??
Did you measure at exactly the same points? 98V is exactly 2X 49V. you must have shaky and measured across V+ and V- after the sparks instead of V+ to common and V- to common.
Matt: The SMPS800R output voltage will slowly decrease during power off sequence to near zero if the amplifier has an idle current draw of at least 50-100mA. If there is no load or the amplifier consume much less, is possible that the output voltage to fall then when reach about half the power supply to restart switching for brief period, increasing the output voltage with 20-30%. this happens because at power down, the capacitors which store the energy for controller and driver section, will discharge much faster than the large caps, because is much smaller, 100 uF at 25V compared with two 1000uF at 200V, and since the large caps are still charged, the small cap will be recharged in about 2-3 seconds and restart the smps for a brief period till most of the stored energy from the large caps is consumed. On board there is a circuit to prevent the power supply restart, there is a resistor divider which supply one pin of the controller ic with a divided voltage from the mains DC bus, so when this voltage drops below ~240V DC the smps will shut-down and will not restart till the power is applied again. However, to be able to work properly in every corner of the world, where the mains voltage can be substantially lower, I decided to reduce this threshold to about 200V. this means that the smps should work also with 180V AC or 90V AC voltage. If the mains supply voltage is stable, over 200V or 100V then the initial values for the divider can be used, so the smps will not restart once is turned off.
On the other hand, the amplifier itself must feature an UVP and OVP protection, not only for this issue but also to prevent erroneous switching frequencies and damage due to excessive bus pumping when is supplied with too low, and too high voltages. The threshold for UVP must be not lower than 70-75% of the nominal supply voltage and the threshold for OVP must be not higher than 120-125% of the nominal supply voltage for safe and reliable operation.
KP, SMPS300R has higher output power and the output voltage is regulated. If set for 24V, will stay still at 24V from zero to max. current. SMPS200QR output voltage is not regulated, and follow the mains voltage +- few percent. for example, will be about 25-25.5V with no load will reach 24V at 2A and will drop to 22V at 6-7A if both rails are paralleled. This power supply has similar behaviour as a classic mains transformer+ rectifier bridge and bulky caps, at a fraction of the size weight and cost, and requiring smaller filtering caps due to high switching frequency ~100KHz. also the efficiency is higher than a classic solution, with 5-10% more. for +-24V or modified single 24V the efficiency reaches 93% at 230V mains and for +-36V efficiency is ~94.5% while a mains transformer+rectifier bridge+caps have an efficiency around 85-88% for the best ones. the reason is obvious, there are lot more losses in few pounds of iron and one pound of copper for a mains transformer than on a tiny smps transformer. both hysteresis losses and I2R losses are greater when the amount of material used is higher, while the losses per gram might be higher for smps transformers.
Peter: I noticed your mail regarding the same issue this morning. I believe, same as DJquan that you measured the voltage across V- and V+
Suppose that the smps was damaged after the short-circuit, there could be two possible type of damage: 1. completely dead, if something couldn't withstand the short circuit, then you would have zero output voltage, and probably blown fuse and 2. loss of output voltage regulation, this happens if the small potentiometer is damaged because the output voltage information for feedback circuit is lost and the smps will increase the output voltage at maximum. In this case, the max. output voltage for +-50V will be about +-75V not more than +-78V. at this output voltage the output caps would be already vented and the rectifier diodes also shorted. there's no way can reach +-98V without serious damage. is already double the nominal voltage.
Also, don't exclude the multimeter error, some cheap multimeters have huge errors when the battery is discharged, as the reference voltage for their ADC drops significantly.
On the other hand, the amplifier itself must feature an UVP and OVP protection, not only for this issue but also to prevent erroneous switching frequencies and damage due to excessive bus pumping when is supplied with too low, and too high voltages. The threshold for UVP must be not lower than 70-75% of the nominal supply voltage and the threshold for OVP must be not higher than 120-125% of the nominal supply voltage for safe and reliable operation.
KP, SMPS300R has higher output power and the output voltage is regulated. If set for 24V, will stay still at 24V from zero to max. current. SMPS200QR output voltage is not regulated, and follow the mains voltage +- few percent. for example, will be about 25-25.5V with no load will reach 24V at 2A and will drop to 22V at 6-7A if both rails are paralleled. This power supply has similar behaviour as a classic mains transformer+ rectifier bridge and bulky caps, at a fraction of the size weight and cost, and requiring smaller filtering caps due to high switching frequency ~100KHz. also the efficiency is higher than a classic solution, with 5-10% more. for +-24V or modified single 24V the efficiency reaches 93% at 230V mains and for +-36V efficiency is ~94.5% while a mains transformer+rectifier bridge+caps have an efficiency around 85-88% for the best ones. the reason is obvious, there are lot more losses in few pounds of iron and one pound of copper for a mains transformer than on a tiny smps transformer. both hysteresis losses and I2R losses are greater when the amount of material used is higher, while the losses per gram might be higher for smps transformers.
Peter: I noticed your mail regarding the same issue this morning. I believe, same as DJquan that you measured the voltage across V- and V+
Suppose that the smps was damaged after the short-circuit, there could be two possible type of damage: 1. completely dead, if something couldn't withstand the short circuit, then you would have zero output voltage, and probably blown fuse and 2. loss of output voltage regulation, this happens if the small potentiometer is damaged because the output voltage information for feedback circuit is lost and the smps will increase the output voltage at maximum. In this case, the max. output voltage for +-50V will be about +-75V not more than +-78V. at this output voltage the output caps would be already vented and the rectifier diodes also shorted. there's no way can reach +-98V without serious damage. is already double the nominal voltage.
Also, don't exclude the multimeter error, some cheap multimeters have huge errors when the battery is discharged, as the reference voltage for their ADC drops significantly.
Hi Cristi,
According to your web site the A1000SMPS uses soft-switch technology not hard-switch as you state above.
Which one is it?
Hi Cristi,
I am looking to eventually power some amps I picked up in the Wire Lateral Mosfet Amp group buy. I know you were intending to create a PS just for that amp, but health problems put that off - I hope you are better now.
I intend to use my Wire amps for biamping individual speaker drivers, so won't have the huge power requirements of most participants of that group buy, but I do want to power the amps for full Class A operation. I see from previous posts that you recommend your SMPS500R for Class A operation and this sounds fine for my 8 ohm midwoofers that I want to power at +-36V or so.
I want your advice on powering 4 ohm tweeters - also in Class A. I preferred running them at +-16V, but I see that the lowest custom voltage you provide is +-18V and that only with your SMPS300RE. I can live with that voltage, but wonder about the SMPS300RE's ability to provide 2 amp biasing since you specifically recommend the SMPS500R for higher bias requirements. If 2 amp is too much for that PS, can you tell me just how much bias the 300 can reliably provide. Also - will there be startup issues with these amps powering up into this bias load? I expect that there may be some additional heatsinking required - will that be a relatively simple addition?
Is this SMPS500R, SMPS300RE combination what you would recommend for my situation?
Thanks for your advice!!
I am looking to eventually power some amps I picked up in the Wire Lateral Mosfet Amp group buy. I know you were intending to create a PS just for that amp, but health problems put that off - I hope you are better now.
I intend to use my Wire amps for biamping individual speaker drivers, so won't have the huge power requirements of most participants of that group buy, but I do want to power the amps for full Class A operation. I see from previous posts that you recommend your SMPS500R for Class A operation and this sounds fine for my 8 ohm midwoofers that I want to power at +-36V or so.
I want your advice on powering 4 ohm tweeters - also in Class A. I preferred running them at +-16V, but I see that the lowest custom voltage you provide is +-18V and that only with your SMPS300RE. I can live with that voltage, but wonder about the SMPS300RE's ability to provide 2 amp biasing since you specifically recommend the SMPS500R for higher bias requirements. If 2 amp is too much for that PS, can you tell me just how much bias the 300 can reliably provide. Also - will there be startup issues with these amps powering up into this bias load? I expect that there may be some additional heatsinking required - will that be a relatively simple addition?
Is this SMPS500R, SMPS300RE combination what you would recommend for my situation?
Thanks for your advice!!
Riileywc: SMPS500R/RS can deliver up to 200W continuous, long term power without forced air cooling. SMPS500RS with heatslug and installed on the housing as heatsink can deliver up to 300W. SMPS800RE can deliver up to 400W, +-60V and +-72V versions. or up to 300W the +-32V or +-40V versions, with convection cooling only. SMPS300RE +-45V to +-60V can provide up to 140W.
using the data above, please consider which is the most appropriate power supply for your application, keep in mind that the max. power required by the amp to be within the power range which the smps can deliver.
using the data above, please consider which is the most appropriate power supply for your application, keep in mind that the max. power required by the amp to be within the power range which the smps can deliver.
cristi I plan on using the SMPS with a Zen v1. I know the single rail 48V version will work for me (not sure if the noise is low enough for such a circuit but I guess I will find out). what I would still like to know is if I could us a dual rail 24V SMPS and still make it work. The reason for this is that I have more use for a dual rail 24V smps then a 48V smps, if it turns out that I don't want to keep using the smps with the zen. Is there any problem with this?
HT Amp Design
Hi all
Cristi i have purchased 2 x Ta3020v3k as the begining of my home theatre system i am looking at running a PC based active Xover 7.4 S/S system i am planning on running 12 of the 3020's in 2 or 3 enclosures based on your following answer
what SMPS would you recomend?
thanks in advance
PS. love your site and all its information
Hi all
Cristi i have purchased 2 x Ta3020v3k as the begining of my home theatre system i am looking at running a PC based active Xover 7.4 S/S system i am planning on running 12 of the 3020's in 2 or 3 enclosures based on your following answer
what SMPS would you recomend?
thanks in advance
PS. love your site and all its information
Cristi,
Still awaiting several requests for answers on the SMPS500R-24Single supply and I have yet another.
I see where a Secondary voltage output of 12V states its capable of 500ma. I have a need for 600ma(continuous) on this circuit. Is this too high, OR can I specify the secondary Voltage at a higher number for a "custom supply"?
Still awaiting several requests for answers on the SMPS500R-24Single supply and I have yet another.
I see where a Secondary voltage output of 12V states its capable of 500ma. I have a need for 600ma(continuous) on this circuit. Is this too high, OR can I specify the secondary Voltage at a higher number for a "custom supply"?
Blt258, I send you mail.
HNCadet, sorry for waiting, is really difficult to have access to real world internet from my location, and recently I can only post on the forum when I'm outside cxina. I wrote here the reasons: http://www.diyaudio.com/forums/connexelectronic/226187-forum-accesibility-issues.html
The value of 500mA for aux. voltage is the average, not the maximum. the linear regulator which ensures regulation from a higher voltage generated from an aux. winding is capable to deliver 1A. If the current is higher, the dissipation will be higher as well, as a product of (Vin-Vout)*I. Currently the transformer aux. winding provide 20-24V but the transformer can be made with a lower voltage aux. winding, of 16-18V so the dissipated power will be lower, as the difference voltage will be lower. Also need to consider that for stable operation, the main output must be loaded with at least 50-100mA while the current demand from aux. exceed 200mA to keep the SMPS within continous mode, not burst mode. Usually this is done by default, as any amplifier power stage quiescent current is at least 50-100mA. In extreme cases, a 5W 1K resistor can be added across the V+ and GND of the main output.
4real: All the power supplies are fitted with large capacitors, usually thousands of uF for 500W SMPS and up, and at least 1000-2200uF each for lower power SMPS like SMPS200QR SMPS240R or SMPS300R(E). these values are much more than necessary for any conventional SMPS, where usually values of hundreds up to one thousand uF are used. But considering that these power supplies are made for audio amplifiers use, and some amplifiers, especially switched ones, class D and T require large capacitance to reduce bus pumping, the caps used are the largest. There are two things which can affect a power supply if the added caps are even bigger:
1. the OC protection might trip during turn-ON sequence if the capacitors are excessively large and require huge current to charge up to their nominal voltage,
2. the control loop stability for regulated type power supplies might be affected if the caps are much larger and the smps can become unstable in some particular working conditions.
For A1000SMPS the maximum recommended capacitance is about 6800uF for +-72V, 10,000uF for +-45V to +-60V and can go up to 22,000uF for lower voltage versions. There is a selection menu for capacitors on the order page for this power supply, and chosing the largest caps is almost always enough for most demanding applications.
HNCadet, sorry for waiting, is really difficult to have access to real world internet from my location, and recently I can only post on the forum when I'm outside cxina. I wrote here the reasons: http://www.diyaudio.com/forums/connexelectronic/226187-forum-accesibility-issues.html
The value of 500mA for aux. voltage is the average, not the maximum. the linear regulator which ensures regulation from a higher voltage generated from an aux. winding is capable to deliver 1A. If the current is higher, the dissipation will be higher as well, as a product of (Vin-Vout)*I. Currently the transformer aux. winding provide 20-24V but the transformer can be made with a lower voltage aux. winding, of 16-18V so the dissipated power will be lower, as the difference voltage will be lower. Also need to consider that for stable operation, the main output must be loaded with at least 50-100mA while the current demand from aux. exceed 200mA to keep the SMPS within continous mode, not burst mode. Usually this is done by default, as any amplifier power stage quiescent current is at least 50-100mA. In extreme cases, a 5W 1K resistor can be added across the V+ and GND of the main output.
4real: All the power supplies are fitted with large capacitors, usually thousands of uF for 500W SMPS and up, and at least 1000-2200uF each for lower power SMPS like SMPS200QR SMPS240R or SMPS300R(E). these values are much more than necessary for any conventional SMPS, where usually values of hundreds up to one thousand uF are used. But considering that these power supplies are made for audio amplifiers use, and some amplifiers, especially switched ones, class D and T require large capacitance to reduce bus pumping, the caps used are the largest. There are two things which can affect a power supply if the added caps are even bigger:
1. the OC protection might trip during turn-ON sequence if the capacitors are excessively large and require huge current to charge up to their nominal voltage,
2. the control loop stability for regulated type power supplies might be affected if the caps are much larger and the smps can become unstable in some particular working conditions.
For A1000SMPS the maximum recommended capacitance is about 6800uF for +-72V, 10,000uF for +-45V to +-60V and can go up to 22,000uF for lower voltage versions. There is a selection menu for capacitors on the order page for this power supply, and chosing the largest caps is almost always enough for most demanding applications.
Hi Cristi
So Ta3020 V3 amp with 18000uF ELNA on board could not be used with SMPS800R 60V ?
Thanks
It can be used if the soft start time is increased otherwise the overcurrent protection might trip.
Some ppls keep asking me by mail why the OC protection can trip if larger capacitors are used, especially if connected to a power hungry amplifier (high quiescent current) as this does not happen with their previous configuration, mains transformer, rectifier bridge, capacitors. The answer is: if the capacitance is much larger than the maximum capacitance allowed for safe and reliable start, the following phenomenon will happen: the soft-start period allows the power supply to start with limited output power capability, thus slowly rising the output voltage to nominal value. This soft start period is finite and last around 100-200ms. Just enough to fully charge the stock capacitors. If larger capacitors are used, the soft-start will ramp-up the output power with the same pace but the capacitors will demand a higher current than the power supply is able to provide to follow the output voltage while charging. then the power supply will enter in OC protection, SMPS will shut-down for a small amount of time, typically one two seconds, and the cycle will repeat with the power supply being reset to minimum output power capability and again slowly ramp-up towards maximum power. BUT.... there's always a butt... if the amplifier or any load connected to SMPS quiescent current is high enough, this will discharge the fatty capacitor which was just about to be charged and at the next soft-start cycle the power supply will have to start-over, because the capacitor was discharged in during the interval when the SMPS was shut-down due to OC condition.
If I would have to make a comparision, is like we try to fill a large bottle with water (capacitor) with a spoon (soft-start) while the bottle has a tiny hole at the botom through the water leak-out (amplifier quiescent current). we can't fill-it as fast as it leaks. Moreover, the power supply trying to start with a killing charge hanged at the output might eventually fail because the very first moment of the start-up the transistors are working in hard-switched mode (with all the related issues of the regarding the body diode and cross-conduction) for few cycles till the converter starts up to steady state. This opperation mode is normal, is described in many papers, and is better to be avoided, thus many conventiona LLC converters would have latched OC protection just to avoid this scenario.
Some ppls keep asking me by mail why the OC protection can trip if larger capacitors are used, especially if connected to a power hungry amplifier (high quiescent current) as this does not happen with their previous configuration, mains transformer, rectifier bridge, capacitors. The answer is: if the capacitance is much larger than the maximum capacitance allowed for safe and reliable start, the following phenomenon will happen: the soft-start period allows the power supply to start with limited output power capability, thus slowly rising the output voltage to nominal value. This soft start period is finite and last around 100-200ms. Just enough to fully charge the stock capacitors. If larger capacitors are used, the soft-start will ramp-up the output power with the same pace but the capacitors will demand a higher current than the power supply is able to provide to follow the output voltage while charging. then the power supply will enter in OC protection, SMPS will shut-down for a small amount of time, typically one two seconds, and the cycle will repeat with the power supply being reset to minimum output power capability and again slowly ramp-up towards maximum power. BUT.... there's always a butt... if the amplifier or any load connected to SMPS quiescent current is high enough, this will discharge the fatty capacitor which was just about to be charged and at the next soft-start cycle the power supply will have to start-over, because the capacitor was discharged in during the interval when the SMPS was shut-down due to OC condition.
If I would have to make a comparision, is like we try to fill a large bottle with water (capacitor) with a spoon (soft-start) while the bottle has a tiny hole at the botom through the water leak-out (amplifier quiescent current). we can't fill-it as fast as it leaks. Moreover, the power supply trying to start with a killing charge hanged at the output might eventually fail because the very first moment of the start-up the transistors are working in hard-switched mode (with all the related issues of the regarding the body diode and cross-conduction) for few cycles till the converter starts up to steady state. This opperation mode is normal, is described in many papers, and is better to be avoided, thus many conventiona LLC converters would have latched OC protection just to avoid this scenario.
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