or Connect
AVS › AVS Forum › Audio › DIY Speakers and Subs › DIY Home Automation
New Posts  All Forums:Forum Nav:

DIY Home Automation - Page 2

post #31 of 58
They look fine, but make sure you get ones with sufficient current rating, and heatsink them if you are going to draw a lot of current through them. The spec sheet has examples.
post #32 of 58
Quote:
Originally Posted by A9X-308 View Post

I'm assuming that this was built for more than just a HTPC (gaming?), otherwise why 64G RAM? A G1610 will play back BR perfectly with the iGPU. I only built mine with a 3770/7790 because I wanted full madVR/SVP and it to be running far from max to keep it quiet.

Just mentioning it in case a reader thinks you need to spend that much for a HTPC.
my htpc runs 30tb of hdd space with only a pentium dual core and 4gb of ram. it used to run fine with only 2gb, but i got leftover unused ram stick.

overkill is all nice and dandy, but it's a waste of resources and energy.
post #33 of 58
Thread Starter 
I just ordered one. $76 with 3-day express air shipping, including their beefiest heatsink.

If it works I'll buy more; and if it doesn't, well... that ones obvious. wink.gif

post #34 of 58
Will be rather impressive if all comes together on the "real cheap". I have home runs of all sorts in two locations and wires ran for irule but just no motivation to start messing with it. My 2 6 zone grafik eyes and 3 wall station key pads were well over $2000 and that's just the lighting part of it all. Your field is a good one now days and I'm sure your DIY automation is quite simple for you to piece together once source what is needed compared to other aspects of your field.

Is it difficult for guys like you to integrate the macro functions like when press play for BD and lights dim down to off, riser step lights go to dim, etc...? It's just so easy to do macros with my Logitech remote so that's all I can compare to.
Edited by audiovideoholic - 12/6/13 at 7:43pm
post #35 of 58
Thread Starter 
It will cost under $800 and give me 16 switchable sockets, of the highest quality, highest power, and with ultimate control. Not too shaby.

If I can find the right hardware doing the lighting for cheap won't be a problem either.
Right now I only have 3 rows of lights, so I don't need 6 zones; but if you DIY it, you can have as many zones as you desire...

Sourcing the exact hardware I need is 99% of the battle for me.
Hey... maybe I should use the Visa Infinite concierge to source all this junk for me, wonder if they have the skillz to succeed? Could be a good test of them! Make 'em sweat for their annual pay. haha tongue.gif
post #36 of 58
Thread Starter 
Ok, I wrote a long winded email to Visa Infinite Concierge of my request.
This will likely push them to their LIMITS of brain-power. I wouldn't be overly surprised if they respond "I don't have a f-CLUE what you are talking ABOUT. I can't find any products that do this, and can't help you at ALL." LOL tongue.gifbiggrin.gif

But if they do come through, then I just found my new BESTEST FRIEND! smile.gif
post #37 of 58
Quote:
Originally Posted by BassThatHz View Post

I just ordered one. $76 with 3-day express air shipping, including their beefiest heatsink.
Ouch.

I got a new post notification, but it has since been deleted. I was going to respond, ýou read my mind' because what soonmation said was exactly what I have done.

" I use MCP23S17 port expanders driving ULN2803 octal darlington drivers and Omron G4a relays because they meet my specs (20A at 240V, 80A surge) and I got a tray of 50 for under a $1ea new."

I use all the same parts, and I also got a tray of 50 for about $60 posted. I had PCBs made for some of them and will redesign a new version over the Xmas hols that also has hall effect current sensors on them so I can monitor each component. Before you ask why, I'm a nerd and got them cheap. PCBs for the new version won't be more than $5 or so.

I've also popped for a couple of these boards for the lower current items such as the AVR (I don't use any of the internal amps), cassette deck, old VCRs etc rather than finish my latching electromechanical design. Not worth the effort for what these cost and they draw almost no power at all.

FWIW, it's 240V where I am.
post #38 of 58
Thread Starter 
Visa Infinite Concierge responded to me with this... thus far:

Dear Mr. Gosling,

Thank you for having Visa Infinite Concierge assist you with your request. Please take a moment to review the information below at your earliest convenience.
This email is to confirm that we have received your request for suitable lighting dimmers and supporting controller for your DIY lighting control system project for your home theater system.

Please allow us some research time in order to find the best options available on the market following your detailed guidelines. You should expect an update no later than 10 PM EST on December 9th, 2013.

Sincerely,

[Name Removed] (Some Russian/Italian female name.)

Your Visa Infinite Concierge
_____________________________________

Sounds good so FAR.... wink.gif

(note: I told them they could take as long as they needed. i.e. not urgent)
post #39 of 58
Thread Starter 
Well Visa Infinite failed me!

I had high-hopes, but my request was "too technical" for them. I won't bother to post their response, as it is too far off target to be of any use to this thread.
This time is was someone from India (some crazy name I can't even begin to pronounce).

I had VISA completely stumped for a full 4 business days. Mission Accomplished I guess smile.gif

I wouldn't expect them to be able to help me reverse engineer a crashed UFO or write artificially intelligent software, but I was expecting a half-decent attempt at sourcing some DIY bulb dimmers.

For non-technical requests, ones that could be understood by a person with an IQ of (not much more than) 100, I'm sure they'd do just fine... LOL wink.gif



As far as the solid state relay, Omega finally shipped it out yesterday, so it will be here any day (maybe even tomorrow).
post #40 of 58
Thread Starter 
The SSR has arrived, OMG this heatsink is ginormous! (I'm scared of this thing redface.gif)

0.7C/Watt
Should be good for full 30amps under 70C



Now let's see if it works!
post #41 of 58
Thread Starter 
I powered it up, and it didn't explode or make a sound. Good so far.

Now I just need to hook some 120volts to it and power something up... maybe start with a lamp, something that I won't loose sleep over if it explodes. smile.gif

post #42 of 58
Thread Starter 
Here it is in action with a small 120v load.



It's alive Igor... it's ALIVE muwhahahah!!!

^^^
Don't play with raw wallsocket power like this at home (or anywhere for that matter).... I'm what you call an idiot, oops, I mean... a professional smile.gif

post #43 of 58
single phase ac normally won't kill a healthy man. it'll give you a nasty shock, but will ground through your skin to earth.
body reflex will cause you to remove your skin from the terminal.

any good reason to use solid state relays when a normal mechanical relay would do the job just fine (and be better suited for the job)?
post #44 of 58
Thread Starter 
Quote:
Originally Posted by paskal9 View Post

single phase ac normally won't kill a healthy man. it'll give you a nasty shock, but will ground through your skin to earth.
body reflex will cause you to remove your skin from the terminal.

any good reason to use solid state relays when a normal mechanical relay would do the job just fine (and be better suited for the job)?

I wanted zero-V x'ing / no nasty transients/sparking of incoming power, that was the main reason for going with this SS model.
post #45 of 58
Quote:
Originally Posted by BassThatHz View Post

I wanted zero-V x'ing / no nasty transients/sparking of incoming power, that was the main reason for going with this SS model.
any benefit to opt for zero crossing to turn on and off the equipment? will prolonged sparking damage the equipment?

reason for my question is that all receivers and processors that i've opened up share one similar trait;
they all used a simple, cheap mechanical relay to turn on the main power supply.
makes no sense to opt for zero crossing when the device itself would still lag with a mechanical relay in it.
post #46 of 58
Quote:
Originally Posted by paskal9 View Post

any benefit to opt for zero crossing to turn on and off the equipment?
Yes, it reduces inrush current during power on.
Quote:
Originally Posted by paskal9 View Post

will prolonged sparking damage the equipment?
It may eventually damage the relay, but this is usually at power down, where the contacts open high on the waveform and with a lot of load, there can be arcing between the contacts. As most people have usually reduced signal to the components before powering down, this is seldom an issue domestically.
Quote:
Originally Posted by paskal9 View Post

reason for my question is that all receivers and processors that i've opened up share one similar trait;
they all used a simple, cheap mechanical relay to turn on the main power supply.
makes no sense to opt for zero crossing when the device itself would still lag with a mechanical relay in it.
It's simple: adjust the time delay from the detection of the zero cross to account for the relay's operation time so that the contact change is at the next zero cross. I have tested a lot of relays and within brand/model they are very consistent with operation time with even large units like my Omron G4a relays having about 100 µseconds between individual units.

'PS' relays in many commercial amplifiers are actually muting the outputs to remove power on/off thumps and have nothing to do with the PS per se.
post #47 of 58
Quote:
Originally Posted by A9X-308 View Post

It's simple: adjust the time delay from the detection of the zero cross to account for the relay's operation time so that the contact change is at the next zero cross. I have tested a lot of relays and within brand/model they are very consistent with operation time with even large units like my Omron G4a relays having about 100 µseconds between individual units.

It would seem that your method of delaying switching has nothing do with the OP's SSRs. I believe that the zero-cross timing is completely built into these SSRs (and all zero-cross SSRs) and cannot be delayed to adjust for mechanical relay delay. He could have used normal SSRs and a microcontroller with a separate zero-cross detector that would have allowed for a delayed switching.
post #48 of 58
Quote:
Originally Posted by NathanJ View Post

It would seem that your method of delaying switching has nothing do with the OP's SSRs.
I was not answering the OP but rather paskal who mentioned sparking which cannot happen in an SSR and contacts, which are not present in an SSR, which implied an electromechanical relay. Did you not notice who I quoted?
post #49 of 58
Quote:
Originally Posted by A9X-308 View Post

Yes, it reduces inrush current during power on.
It may eventually damage the relay, but this is usually at power down, where the contacts open high on the waveform and with a lot of load, there can be arcing between the contacts. As most people have usually reduced signal to the components before powering down, this is seldom an issue domestically.
It's simple: adjust the time delay from the detection of the zero cross to account for the relay's operation time so that the contact change is at the next zero cross. I have tested a lot of relays and within brand/model they are very consistent with operation time with even large units like my Omron G4a relays having about 100 µseconds between individual units.
i knew i've read it somewhere. it's here.

i have nothing against solid state relays, but using them and expecting lower inrush isn't justified. it's even graphed in his result.

probably explains why all inrush limiting circuits for audio equipments that i've seen uses simple mechanical relay in them.
might be good for turn off though, especially when you have something like the LG clone wasting that much current in idle. tongue.gif
Quote:
Originally Posted by A9X-308 View Post

'PS' relays in many commercial amplifiers are actually muting the outputs to remove power on/off thumps and have nothing to do with the PS per se.
they would, if they're located somewhere at the signal output.
but they're not at the amp modules, they're in the power supply line, usually close to the AC jack. biggrin.gif
post #50 of 58
Quote:
Originally Posted by paskal9 View Post

i knew i've read it somewhere. it's here.


In theory it is, but in reality, it's not. To save me typing, here is a short video explaining why the reality differs.
http://www.youtube.com/watch?v=kn9QOF5d-Sw (start at 1:15)
Quote:
Originally Posted by paskal9 View Post

it's even graphed in his result.
Where? None of the current graphics show a typical transformer/capacitor mains inrush.
What you may also not know is that a discharged capacitor is an effective short circuit, so applying any voltage at switch on will cause a large inrush as they try to fill, limited by Zsource.
Quote:
Originally Posted by paskal9 View Post

probably explains why all inrush limiting circuits for audio equipments that i've seen uses simple mechanical relay in them.
Most of those that do use a series resistor or thermistor in series with the TRF primary which the relay bypasses once the (limited) inrush period has passed.
post #51 of 58
Quote:
Originally Posted by paskal9 View Post

probably explains why all inrush limiting circuits for audio equipments that i've seen uses simple mechanical relay in them.

Have a look at the Bryston power amp schematics on their web site. Their inrush current limiting uses an interesting circuit involving triac phase control. At startup, a triac that serves as the high-power portion of the power on/off switching is initially set to have a conduction angle of zero, and the conduction angle is slowly increased to full conduction to minimize inrush current. Earlier versions of their amps used a TDA1085C chip, originally designed for washing machines biggrin.gif, for the triac phase control. The latest versions of their power amps use a microcontroller and peripheral circuitry to control the triac conduction angle at startup.
Quote:
Originally Posted by paskal9 View Post

they [the muting relays] would [reduce transients], if they're located somewhere at the signal output.
but they're not at the amp modules, they're in the power supply line, usually close to the AC jack. biggrin.gif

Have a read of the power amp design books by Self and by Cordell. Virtually all solid state power amps have an electromechanical relay at their output. This is to protect from turn-on and turn-off thumps, but it's also deactivated when excessive dc is detected on the output.
post #52 of 58
The mechanism that causes sparking is inductance, which means you want to do zero current switching, not zero voltage. As the change in current happens faster, the resultant voltage approaches infinity (V=L x dI/dT): but what happens in real life is the air ionizes and creates a breakdown channel for current to flow, and thus the sparking you see.

With that in mind, the only time voltage and current are in phase is when the power factor is 1, which unfortunately is nowhere near the case for most audio amplifiers (unless they're advertising power factor correction). At best, you might expect a power factor of 0.7, but it can get as low as 0.3 in some cases I've seen....At which point, zero voltage switching is about as worse as you can get, ooops!

One way to reduce the inductive kick is to place a capacitor across the switched nodes of the relay. This creates an AC short so the current can flow through the capacitor without sparking (hopefully). It also creates a resonant tank which can lead to destructive oscillation voltages, so it needs to be designed correctly. A reverse diode across the control leads of the relay also helps to shunt oscillations that can cause bouncing of the relay contacts, which is actually more problematic for wear and tear from sparking.

Who woulda thought a simple switch could be so complicated? wink.gif
post #53 of 58
Quote:
Originally Posted by MBentz View Post

The mechanism that causes sparking is inductance, which means you want to do zero current switching, not zero voltage.
At switch ON, both V and I are zero, so you want to switch at V zero cross. See the video I linked earlier.
Quote:
Originally Posted by MBentz View Post

As the change in current happens faster, the resultant voltage approaches infinity (V=L x dI/dT): but what happens in real life is the air ionizes and creates a breakdown channel for current to flow, and thus the sparking you see.
In low current devices like a DVDP, there is so little current draw, there is never going to be an arc. In a high power amplifier, at idle the draw is still modest. For example my P7000S is 120W which is where most people are going to turn it off most of the time, so again, little risk of arcing with a suitable relay. Even then, an occasional arc is not going to destroy a relay, that takes may thousands of operations where arcing occurs.
Quote:
Originally Posted by MBentz View Post

With that in mind, the only time voltage and current are in phase is when the power factor is 1, which unfortunately is nowhere near the case for most audio amplifiers (unless they're advertising power factor correction). At best, you might expect a power factor of 0.7, but it can get as low as 0.3 in some cases I've seen....At which point, zero voltage switching is about as worse as you can get, ooops!
Somewhere between 1 and 0.7 is what you are going to see in the network in the distribution phase. I am very dubious about a normal poweramp being around 0.3; I'd need to see that for myself.
Quote:
Originally Posted by MBentz View Post

One way to reduce the inductive kick is to place a capacitor across the switched nodes of the relay.
Capacitors are pretty ineffective for arc suppression which is why they're not used very much in high power or high reliability switching.
post #54 of 58
Quote:
Originally Posted by A9X-308 View Post

At switch ON, both V and I are zero, so you want to switch at V zero cross. See the video I linked earlier.
In low current devices like a DVDP, there is so little current draw, there is never going to be an arc. In a high power amplifier, at idle the draw is still modest. For example my P7000S is 120W which is where most people are going to turn it off most of the time, so again, little risk of arcing with a suitable relay. Even then, an occasional arc is not going to destroy a relay, that takes may thousands of operations where arcing occurs.
Somewhere between 1 and 0.7 is what you are going to see in the network in the distribution phase. I am very dubious about a normal poweramp being around 0.3; I'd need to see that for myself.
Capacitors are pretty ineffective for arc suppression which is why they're not used very much in high power or high reliability switching.

You still have to switch the device OFF....and even with 1mA of current, an instantaneous change in current still approaches infinity volts. That's just how the math works out. In practice is definitely different, but my point about the math is the truth here about sparking - which is the only issue I was addressing. You won't get any spark switching with 120V and no current flowing because 120V won't conduct through the air. Sparking is entirely related to switching current - not voltage. EMI can be generated from interrupting either current or voltage. You're just choosing between a magnetic or electric field generation for the EMI wave generated.

An inductor has a power factor of zero. When an amplifier is in idle, you are driving the primary inductor of the input transformer....but since some power is being used and you're connected to a capacitor tank circuit on the output you won't see the power factor drop all the way to zero. You can doubt it all you want, but I've measured this personally - in fact, it's even part of my job to quantify the power factor of the audio equipment I design, which gets verified by compliance organizations all over the world. The power factor moves all over the place depending on the output power the system is delivering. Without PFC, 0.3 at idle is very reasonable. How many measurements have you seen personally? Keep in mind that I'm saying the PF will improve as output power is increased, and you generally don't get above 0.7 for non PFC designs.

The reason capacitors aren't used in AC systems is because the capacitor value to have an appreciable effect on the voltage spike will end up leaking AC current when the switch is off, plus the required voltage rating makes it physically very large, etc... I brought it up as a conceptual understanding of what the current is trying to do (which is keep conducting).

If you've got a bouncing relay drive, then you only need a few dozen switches before you can measure increased impedance across the relays switched nodes due to the arcing that occurs. You can even get them to latch up because they end up welding together.


To be honest, I'm not sure what problem you're trying to solve with zero-voltage switching on an AC relay. You're arguing the sparking doesn't matter.
post #55 of 58
Thread Starter 
Today I purchased 14 20amp sockets and 20amp switches for the equipment rack relay-box(es).





I also purchased some more plug-ins for the cleanboxes, they are low power but take up too much space for direct connections.



One step closer and one less thing on my huge list of to-do things.
post #56 of 58
Thread Starter 
Check it out. Got the relays working over Wi-Fi from a tablet.

Running VirtualRouterPlus on my HTPC to establish a tethered WPA2 802.11 connection to the tablet.

Navigate to the bookmarked website with chrome on the tablet.




I might look into coding an android app to make it even sexier, but baby steps first...
Edited by BassThatHz - 2/13/14 at 11:10pm
post #57 of 58
Quote:
Originally Posted by BassThatHz View Post

Check it out. Got the relays working over Wi-Fi from a tablet.
Neat.
I'm trying to code an app for my system to run off a basic 7" tablet I picked up this week. I expect it will be a (very long) while before it works.
post #58 of 58
Thread Starter 
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: DIY Speakers and Subs
AVS › AVS Forum › Audio › DIY Speakers and Subs › DIY Home Automation