Topic: Thinking of building a power conditioner

[BCostigan]

I've been thinking about building one....not that I can do it any cheaper or even better than those out there but it's snowing again and I'm bored. 


My plan is to feed 3-4 hubbell hospital grade duplex receptacles  each with a 250VA isolation transformer. One duplex receptacle would be supllied buy 2 250VA isolation transformers connected in paralell. This duplex receptacle would be designated for the amp(s).  I would also have some sort of resetable overcurrent protection @ 15A.    This would all be in some type of hammond enclosure...not sure which one yet.


What do you guys think?  I'm trying to decide if I want to make it the size of a component and have it with everthing else.....if so the chasis would be 17"x10"x4".   Would it be better on the floor?

I'm also working on the "blinky light factor".   Power indicator led, toggle switch on/off, volt/amp indicators (trying to find some lighted analog ones  )



Any ideas on how I can best do this or even where to find some of the parts is VERY appreciated!

[Lil Kim Jong-Il]

I think it's a great idea.

check out the jon risch balanced power conditioner:

http://www.geocities.com/jonrisch/catch2.htm

he has some parts listed in his paper.

[Tim]

very cool Brian! go for it...

[BCostigan]

I think it's a great idea.

check out the jon risch balanced power conditioner:

http://www.geocities.com/jonrisch/catch2.htm

he has some parts listed in his paper.

+T for that.  I think tracking down the right parts is gonna be the toughest part!

[ducati]

Equitech sells blem transformers.  Here's the link:
http://www.equitech.com/products/seconds/seconds.html

5A is a little low for many amps; I'd like a little more headroom in there.

[BCostigan]

Equitech sells blem transformers.  Here's the link:
http://www.equitech.com/products/seconds/seconds.html

5A is a little low for many amps; I'd like a little more headroom in there.

Thanks for that link.  +T 

One of the transformers elbarto listed is rated at 8A.  8A should be plenty for me even if I get a center, sub, and surrounds and crank the whole system.  Even with all speakers being driven my amp shouldn't pull more than 700 watts or 5.8A.  This leave me with 2.2A for CD/DVD etc which is plenty.


The enclosure is troubleing me.  What do you guys think?  If it were you would ya want the unit on the floor or in your rack?  The size of the transformers is kinda throwing things off........

[BCostigan]

Well....here's what I've decided on so far:

Enclsure:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4660&item=3880323760


Transformer:
part#798.1202;  115primary/115secondary; 1000VA toroidial isolation transformer
http://www.toroid.com/standard_transformers/isolation_transformers/isolation_commercial.htm#Data


Volt meter (blinky light fun factor):
http://www.martelmeters.com/products.php?cat=16&action=detail&id=83


The front face will have:
crome toggle that turns the whole unit on/off
blue led power indicator
voltmeter listed above
10A panel mount replacaeable bus type fuse

Rear panel will have 6 hospital grade duplex receptacles.


I'm thinking for an increased fun factor I could add 6 more toggles and indicator lamps (one per outlet) so that I could turn individual components on and off.....maybe even fuse them individually based on manfgr. specs for max current draw.


This is gonna be fun!     Now to appropriate the funds to build this thing....looks like the parts cost is about $400 ($300 minus the voltmeter).

[Nick in Edinboro]

Brian,

I know that some power supply thingies I have seen have shyed away from using a lot of lights/etc. as they believe it could introduce noise into the signal?

Just a thought.  Not sure what with all the blinking lights and all if that is a concern on a power conditioner.  I'd rather have a bleak black box with an on switch than a fancy blinky one that introduced noise.

[MattD]

Brian, since you're the electrician, I'm sure you can answer this one: Why not use a PTC resettable type of fuse? Are they not as safe as glass fuses or some other kind that actually "blow" and need to be replaced? Are they meant for smaller currents (more in the 1A range, than the 10A you propose)?

[BCostigan]

Good point Nick!   I was actually thinking I'd need to add another small xfmer for the lights etc due to voltage constraints.....good call no blinky lights! (well one non blinky 120v indicator)



Matt.....quite honestly I'm not too familiar with PTC fuses.  I decided to go with a bus type fuse because:

it's cheap, effective, and fuses are readily available
A resetable option leaves the window open for operator error. 


By operator error I mean than people (myself included from time to time) usually just keep resetting and triping the device until the problem gets "cleared" or the overcurrent device burns out.  Forcing the operator to change the fuse gives them time to think "hey....maybe somethings wrong".

[Nick in Edinboro]

Good points on the resettable fuse too Brian...

I'd be interested in seeing what you can make this for cost wise... sounds like a fun project none the less.  What is your highest cost now sans blinky lights?

Are the hubbell receptacles now the most costly part?  Being our resident electron mover and shaker, I ask you, what is it about these "hospital grade" receptacles that makes them so expensive?  I just wonder if other specialized receptacles used in other applications other than in the hosipital where clean power is a must are any cheaper but of similar build quality, etc.

Does the "toroidial isolation transformer" somehow clean and hold the power?  I am so n00bish I feel dumb asking that question     I do know that my amplifier has one though 

Then again, I know virtually nil about electrical stuff so who knows

[BCostigan]

Cost is still about $400 with voltmeter $300 without.   I was going to power the voltmeter off the load side of the xfmer terminal bus....I guess I could put one on the line side as well but it's cost prohibitive.



Hospital Grade receptacles.  There are 3 "grades" of receptacles: standard (what most folks have in their house), commercial, and hospital grade.  Hospital grade receptacles are just the most rugged well made of all 3 categories.  Hospitals have their own set of standards for elec, gas, plumbing etc. that are more strict compared to most buildings.  All installations but be of the highest quality for obvious reasons.

Hubbell just has the most respected name in the business.  If the local supply house quotes me a significantly better price on another brand I'll go with them.  I don't expect to pay more than $10 per duplex.


If anyone wants me to build this for them I'd be happy to!  You just buy the parts I'll donate the labor as I'd like to make a prototype and maybe try selling these.

[Nick in Edinboro]

Hubbell just has the most respected name in the business. If the local supply house quotes me a significantly better price on another brand I'll go with them. I don't expect to pay more than $10 per duplex.

Thanks for the good explaination!  I've seen those wall recepticals priced so high ($49) that I was curious why not go with a lesser known brand that is also hosipital grade ($15ish).

Neat stuff..!

[BCostigan]

Brian,

Here is more to chew on;
http://www.marinco.com/hospital.htm

I'm clueless to pricing, quality comparison, availability, etc. I just thought I'd throw this out there as another possible source for you.

Thanks Moke.   I'm also wondering if I should hard wire the unit or use a female IEC connector......

[BCostigan]

IEC

That's what I figured too.....the cost keeps going up!