Have a question for those with expertise in this area...
I am planning an active 3 way system with 6 channels of purifi amplification. I know that the smps used for these modules can be configured to run on 240V as well as 120V. I am in the US and have 240V available at my breaker box. I am pondering running a 240V feed to a 240V outlet and running the amps with the smps' set at 240V. I would use powercon plugs and a 30A breaker in the breaker box. I thought this would make more sense than running multiple circuits to multiple outlets.
Any cons to the idea?
I am planning an active 3 way system with 6 channels of purifi amplification. I know that the smps used for these modules can be configured to run on 240V as well as 120V. I am in the US and have 240V available at my breaker box. I am pondering running a 240V feed to a 240V outlet and running the amps with the smps' set at 240V. I would use powercon plugs and a 30A breaker in the breaker box. I thought this would make more sense than running multiple circuits to multiple outlets.
Any cons to the idea?
Yes, definitely. The con is that your USA 230/240V is not ground referenced. Instead it consists of two hot leads, at a potential of -120VAC and +120VAC (or you can think of it as two 120VAC voltages that are 180 degrees out of phase with each other). Bad things can happen when you accidentally connect what you think is the "ground" of your USA 240VAC line to ground=earth=0V, which is what all your other components will have. Of course this all depends on how the equipment is designed, but I would not risk it.
You can get around this using a big transformer to ground reference the 240VAC circuit, but why not just use your 120VAC power?
You can get around this using a big transformer to ground reference the 240VAC circuit, but why not just use your 120VAC power?
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Thanks for your reply.
Are you saying that I could have issues if I ran the two hot legs and a ground wire attached to the actual grounding lug in the breaker box to the amps and tied the ground from the modules and smps to that actual ground from the breaker box?
Why not just use 120V? I think I stated that above.
Again, appreciate your reply.
Are you saying that I could have issues if I ran the two hot legs and a ground wire attached to the actual grounding lug in the breaker box to the amps and tied the ground from the modules and smps to that actual ground from the breaker box?
Why not just use 120V? I think I stated that above.
Again, appreciate your reply.
What are the exact amp(s) or amp module(s) that you are planning to use?
Scratch that, what is the SMPS you want to use? Have you looked at its datasheet regarding AC input?
Scratch that, what is the SMPS you want to use? Have you looked at its datasheet regarding AC input?
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The AC input is marked Neutral AC and phase AC.
I would not run 220 in this case.
Also not much to be gained in this case.
I would not run 220 in this case.
Also not much to be gained in this case.
OK, I took the time to download and read the datasheet. Have you done that, and do you understand it?
Here is what I get from it - I will try to walk you through it. The attached pic is the spec for the AC mains input terminals. There are two terminals only: Neutral and "Phase AC". Remember, in the USA all you have is two 120VAC lines (the two hot lines of your USA 240VAC circuit) plus a ground (a ground wire is not intended to carry any working current). There is no "neutral" line.
The reason that this and many other SMPS can operate on 120VAC or 230/240VAC is that the manufacturer would like to sell the same module to the world. For example to USA with AC coming on Neutral+120VAC and to Europe where AC comes on Neutral+230VAC. But both input voltages require a single ended mains AC and the USA 240VAC does not have one.
I hope it is clear now why your idea to get around multiple branch circuits and multiple SMPSs won't work, not with this SMPS and not with pretty much every other SMPS out there unless it has been designed to use "balanced power". I don't know of any off hand, but maybe they exist.
But let's take a step back and think about what you need for your 6 Channels of amplification. The Purifi amp modules are rated at about 400W/ch, and times six channels this is 2400W. But this SMPS is only capable of 1200W total output, so you will need two anyway. This will provide some headroom in the SMPS and will help it to run cooler. I suggest you install two 20A dedicated branches and run three amp channels off of each SMPS. Putting all six on one SMPS will work only if you can limit the total output power to about half the total capability of the amp modules.
Here is what I get from it - I will try to walk you through it. The attached pic is the spec for the AC mains input terminals. There are two terminals only: Neutral and "Phase AC". Remember, in the USA all you have is two 120VAC lines (the two hot lines of your USA 240VAC circuit) plus a ground (a ground wire is not intended to carry any working current). There is no "neutral" line.
The reason that this and many other SMPS can operate on 120VAC or 230/240VAC is that the manufacturer would like to sell the same module to the world. For example to USA with AC coming on Neutral+120VAC and to Europe where AC comes on Neutral+230VAC. But both input voltages require a single ended mains AC and the USA 240VAC does not have one.
I hope it is clear now why your idea to get around multiple branch circuits and multiple SMPSs won't work, not with this SMPS and not with pretty much every other SMPS out there unless it has been designed to use "balanced power". I don't know of any off hand, but maybe they exist.
But let's take a step back and think about what you need for your 6 Channels of amplification. The Purifi amp modules are rated at about 400W/ch, and times six channels this is 2400W. But this SMPS is only capable of 1200W total output, so you will need two anyway. This will provide some headroom in the SMPS and will help it to run cooler. I suggest you install two 20A dedicated branches and run three amp channels off of each SMPS. Putting all six on one SMPS will work only if you can limit the total output power to about half the total capability of the amp modules.
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I live in Canada so our power is the same as USA.i've worked on lots of stuff in NA that was run on 240AC 4 wire . The 4 wire was phase A phase B, neutral and ground. The neutral and ground were connected together at the building distribution panel. Inside the equipment were 240 volt parts and 120 volt parts. Problems arose when the neutral would get corroded or loose. One side might be 160 and the other side 80 oops. If the SMPS. Has 3 connections ie hot neutral and ground and the neutral and ground are not connected you should be ok. Why a 30 amp breaker? 7.2KW is a lot of audio.
Kitchen counter outlets are 240 volt between the 2 hots. And 120 between hot and neutral.
When I wired up my pool pump I only use 3 wires. Phase A phase B and ground. No neutral. I have wired lights, battery charger, power supplies and an out door stereo all on 240. The lights and everything are rated at 240.
Kitchen counter outlets are 240 volt between the 2 hots. And 120 between hot and neutral.
When I wired up my pool pump I only use 3 wires. Phase A phase B and ground. No neutral. I have wired lights, battery charger, power supplies and an out door stereo all on 240. The lights and everything are rated at 240.
I have looked into this a bit deeper and everything I have read on line says there should be no problem, in general, with running a smps off of 240V balanced (split phase) power. Here is one thread on an electronics forum:
Switching Power Supply on North American 240v AC (split phase) - Page 1
I plan to use 3 of the hypex smps1200A400 for the 6 purifi modules, not 1 or even 2.
Yes, I looked at the data sheet and didn't find anything that seemed to address this issue directly.
I have also emailed hypex for their advice.
Thanks to all who took the time to reply. Much appreciated.
It would be much simpler, cheaper, and easier to run one circuit instead of 3- less copper, fewer breakers, fewer outlets, fewer power cords.
I will report back when I hear from Hypex but from what I am finding on ee forums, etc., seems people are doing this without any issues.
Switching Power Supply on North American 240v AC (split phase) - Page 1
I plan to use 3 of the hypex smps1200A400 for the 6 purifi modules, not 1 or even 2.
Yes, I looked at the data sheet and didn't find anything that seemed to address this issue directly.
I have also emailed hypex for their advice.
Thanks to all who took the time to reply. Much appreciated.
It would be much simpler, cheaper, and easier to run one circuit instead of 3- less copper, fewer breakers, fewer outlets, fewer power cords.
I will report back when I hear from Hypex but from what I am finding on ee forums, etc., seems people are doing this without any issues.
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I would definitely wait to hear back from Hypex. And when you do please post here. If their SMPS actually can run on balanced (not ground referenced) AC I would like to know.
The datasheet is pretty clear: the mains AC for the SMPS has only two connections. One of these is labeled "Neutral" in the datasheet. What do you plan to connect there? And then what would you connect to the other input, labeled "Phase"??? Think about it!
The datasheet is pretty clear: the mains AC for the SMPS has only two connections. One of these is labeled "Neutral" in the datasheet. What do you plan to connect there? And then what would you connect to the other input, labeled "Phase"??? Think about it!
SMPS1200A400 can deliver just under 400W continuously. 3 of them would be just shy of 1200W. A120V 20A outlet can deliver 2400W continuously. I realy can't see the problem her.
Hypex Electronics B.V.
It gives up to 1500W cont., 1200W at 20Hz
It is a very good switched mode resonant type, which works with high frequency sine, not square wave. Minimum interference with audio, lees than a mains transformer PS.
It gives up to 1500W cont., 1200W at 20Hz
It is a very good switched mode resonant type, which works with high frequency sine, not square wave. Minimum interference with audio, lees than a mains transformer PS.
It says MAX 1500W, and MAX 1200W @20Hz. That is the power for a tiny fracktion of a second. Continuous power is under 400W. That is the important number with regard to the house circuit.
Sure, 400W is the max average/continuous, but without PFC it will have spikes in the current draw just like any other PS. I'm liking SMPS that feature active PFC more and more these days, at least for high power applications.
From Hypex:
"Hello Chris,
Yes, the SMPS will work on two phase 240V.
Kind regards,
Jos Wolthuis | Hypex Electronics BV | Technical Support Engineer | Hypex Electronics B.V. | "
So they can indeed be supplied with split phase 240V.
One smps requires 1200W. One 15amp US outlet is rated at 1800W max. I will have 3 of these 1200W smps' so 3 x 1200W = 3600W, or twice the rating of a single 15A 120V outlet. See the problem? The simplest solution is to run one 240V feed and eliminate all the extra wiring, outlets, cords, plugs, etc.
Thanks again for the replies.
"Hello Chris,
Yes, the SMPS will work on two phase 240V.
Kind regards,
Jos Wolthuis | Hypex Electronics BV | Technical Support Engineer | Hypex Electronics B.V. | "
So they can indeed be supplied with split phase 240V.
One smps requires 1200W. One 15amp US outlet is rated at 1800W max. I will have 3 of these 1200W smps' so 3 x 1200W = 3600W, or twice the rating of a single 15A 120V outlet. See the problem? The simplest solution is to run one 240V feed and eliminate all the extra wiring, outlets, cords, plugs, etc.
Thanks again for the replies.
You can try to draw 1200W countinuous from each smps. I bet the smsp burn up long before the fuse blows.
the peak currents are not what limits your main fuse. Your 20A 120V circuit would handle 40A peak without problems.
Regardless, the 120V circuit(s) require at a minimum twice the components. It seems to me the 240V circuit has 0 downside and saves on power cords, inlets, etc.
I could of course run a 240V feed and wire the two outlets in a 120V receptacle using each phase and get two 120V outlets, but then I would still need two power cords, two inlets. Doesn't make much sense at all if the smps can run on 240V split phase.
I could of course run a 240V feed and wire the two outlets in a 120V receptacle using each phase and get two 120V outlets, but then I would still need two power cords, two inlets. Doesn't make much sense at all if the smps can run on 240V split phase.