Over at smarthome.com you can pick up a power meter for a few $$$:

http://www.smarthome.com/9034.html
http://www.smarthome.com/9033.html
http://www.smarthome.com/9055.html

I ran a couple of 20 amp circuits for my farm and then balanced them using the meter at http://www.smarthome.com/9034.html

---

Thanks for your help everyone. I hope to look into it more this weekend. I already have a variety Multimeters, Ampmeters and A dual trace digital storage O-scope w/ PC interface. I'm also aware of the RMS , peak, peak-to-peak and spikes generated by output capacitors and other devices.
What I really lacked was knowlecge in household wireing. namely knowing how much current I'm allowed by electrical codes to run though a certain gauge of wire. thus determining the limit of the breaker on that leg and the # of PCs that I can put on that breaker/leg.

This weekend I plan to turn on the TV DVD VCR A/C that is on the same breaker that my PCs are on then turn on 1 PC at a time let it boot/stabalyze and run Boinc. once the breaker kicks I'll back off a few PCs.(Fire exstinghisher in hand). A guy is also comeing by this weekend to discuss adding a seperate circuit just for My PCs. I'm sure he will need to know the current consumption of all of the PCs. I plan to record the current during bootup as well as idle and with Boinc.
I think it is not only important to know the current draw under full load but also when booting. PCs draw a large amount at that time and if the power "flicker" and reboots all the PCs then they will all be rebooting at the same time. so it should be considered. Like wise I'm open to anything any of you have to say.
and once again.. thanx for the help and advise.

<blockquote> I think it is not only important to know the current draw under full load but also when booting. PCs draw a large amount at that time and if the power "flicker" and reboots all the PCs then they will all be rebooting at the same time. so it should be considered. </blockquote>

Wise to check yourself. The start up current draw for mine was the same as when Boinc was running (100% cpu use is 100% Cpu use). Mine went 800+ mA at start up, down 228 mA after loading windows, then back up to 800+ when Boinc running.

If you're using a Monitor, check that too, plus Printer, UPS, ETC.

<blockquote>There is an explaination somewhere on Flukes engineering pages if you rquire further education</blockquote>
Do you have a link?
<blockquote>or try looking at the current waveform using an ocilloscope.</blockquote>
I've checked the mains voltage to chopper power supplies so many times it's not funny.
Getting spikes such as you're describing on the supply mains of a power supply would indicate one seriously faulty PSU.

---

Grant
Darwin NT

come on guys. I don't think he needs to create a "White" paper, just to replace a recept and maybe have a "fully licensed" electrician install a new branch circuit. I believe he's fully equipped (both mentally, and equipment) to achieve this minor task. If he uses 2A per puter he's probably safe. If not then the breaker will trip, telling him he's wrong.

About the new Branch circuit. As I stated earlier most recepts are capable of carrying 15 amps. If it's the only one hooked up to a 20A CB then you can conceivably "Smoke" the recept without tripping the breaker (atleast until the smoking recept mechanically fails and the internal parts actually touch eachother). So, If you're planning on a single "Duplex" receptacle on a 20A CB then get the 20A rated recept. Or, just install more than one 15A recept and divide the load.

Oh yeah, NFPA 70 says you can have a max of 10 outlets on a 15A CB and 13 on a 20A CB (as long as they are just for recepts, NO lighting loads/circuits attached)

As to the initial higher currents, This branch circuit is protected by a Circuit Breaker. Circuit breakers are designed to trip when a higher current is present over a longer period (cycles). They trip via a Thermal mechanism. They will allow many cycles well above the "Rated" trip current before tripping. If "inrush" is a problem then go with Fuses. If SCRs are involved, go with Inverse Time fuses that can break the flow within a 1/4 cycle.

tony

Do you have a link?

http://www.informationstore.net/fluke/efulfillment.asp?publication=10047-eng

Its a pdf, the plot is on the right, half way down second page.

---

<blockquote>Thanks for your help everyone. I hope to look into it more this weekend. I already have a variety Multimeters, Ampmeters and A dual trace digital storage O-scope w/ PC interface. I'm also aware of the RMS , peak, peak-to-peak and spikes generated by output capacitors and other devices.
What I really lacked was knowlecge in household wireing. namely knowing how much current I'm allowed by electrical codes to run though a certain gauge of wire. thus determining the limit of the breaker on that leg and the # of PCs that I can put on that breaker/leg.</blockquote>

My ex-boss has my wiring book, so I'm doing this without a net.

Answers for the U.S. only, check codes with your local government, prices slightly higher west of the rockies, no animals were injured preparing this response.

For an existing circuit in the typical home, there will be a three prong socket (called L5-15) -- the two main prongs are aligned vertically, with a round ground.

You are allowed to draw 15 amps from this circuit, and if your electrician did his job, the wire will be adequate for 15 amps continuous -- not per outlet but for all outlets on the branch. There will be a 15 amp breaker.

According to the National Electrical Code, a UPS plugged into a 15 amp circuit may not draw more than 12 amps.

An L5-20 outlet is good for 20 amps, and one of the prongs is turned 90 degrees to the other. The socket takes 15 amp style and 20 amp style plugs.

If this is confusing, let me know and I'll take some pictures, I have both.

If you are doing this yourself (check local laws, you may need a licensed electrician to do the work), I'd calculate the proper wire size based on the length of the run, and use the next larger wire. 15 amp circuits are usually 14 gauge wire, so I generally use 12ga -- it's readily available and only a little bit more expensive than 14ga.

Of course, if you have any questions, consult a licensed electrician.

This link might be of interest: http://www.taunton.com/finehomebuilding/pages/h00009.asp

---

<blockquote>A guy is also comeing by this weekend to discuss adding a seperate circuit just for My PCs. I'm sure he will need to know the current consumption of all of the PCs. I plan to record the current during bootup as well as idle and with Boinc. </blockquote>

One more comment:

The cost of having this guy pull a dedicated circuit is mostly labor.

While you're at it, you might have him put in two circuits -- he can pull the wires together, so it only adds a little bit of work to put in extra outlets at each end, and the cost of another breaker (probably $10 or less, assuming there is room in the panel).

---

Just to update:
I managed to get 7 PCs up and running without and additional wireing on 2 seperate breakers. I found one breaker just for the sprinkler system that is broke at the moment( I didn't do it!) and used it to power 4 PCs.
oddly though my roomate( who doesn't know that The breaker I'm useing is solely for the sprinkler ) asked me to see if I can fix the sprinkler.LOL.HMMMM let me see. NOPE I can't fix it. I don't know anything about that stuff. maybey you should call in someone to put in a new circuit. Seems like it ain't getting any juice. Then maybey we can solve all the power problems we been haveing.hehehe

One PC did lock up though after the 1st day. It is a new pc(new to me...given to me for some computer help that I helped a coworker with) It is the only Celeron in the house. no fan either except for the power supply. I've shut it off for now til I can determine if it is heat or my "cracker Kitty" (aka Lord Stryk3r) on the keyboard again. There where a lot of open windows on the box that I didn't open.
most of the windows where Visual C++ so maybey Lord Stryk3r is learning C language while I'm not around. I'm goin to keep my eye on this feline phreaker.

HELP. I'm ready for help now. I spent three days downloading Overclockix 3.8. I'm trying to Burn a bootable CD. I searched the knoppix site, and found a link to "how to burn CD". Unfortunately, it's in German and the only thing I can do in German is to order a beer. LOL

I have "HP Record Now" it offers three options "Disc to disc copy", "make a music CD", and "Make a data CD". I copied all the Knoppix files using "make a data CD" and it didn't work. I read I need to burn it in a "ISO image". I don't find that option on my program.

Is there a shareware program I can use?

tony

You can download a copy of Nero and burn an ISO with it, I think the evaluation copy is good for 30 days.Good Luck.

---

HELP. I'm ready for help now. I spent three days downloading Overclockix 3.8. I'm trying to Burn a bootable CD. I searched the knoppix site, and found a link to "how to burn CD". Unfortunately, it's in German and the only thing I can do in German is to order a beer. LOL

I have "HP Record Now" it offers three options "Disc to disc copy", "make a music CD", and "Make a data CD". I copied all the Knoppix files using "make a data CD" and it didn't work. I read I need to burn it in a "ISO image". I don't find that option on my program.

Is there a shareware program I can use?

tony

Tony,

could you please have a look over here , i'm not quite sure, but it looks as it could help you out of the catch-22.

regards
rattelschneck

thanks.

This is going to be an interesting learning experience.

tony

thanks.

This is going to be an interesting learning experience.

tony

Just a thought - communicating such issues in the fora isn't very efficient.
Do you use some kind of instant messaging client?
Could be easier.

I believe that if you look MS has "officially" stopped supporting 98 so I believe it is now legal to use without a license.

Windows 98 is still supported (3rd world still use it so microsoft had to be seen to "care") still unlikly to cause license problems though.

Other option would be to subscribe to MAPS (have to have set up a "computer business" but for around £250 you get multiple licences of basically all Microsoft products, from SBS 2003, XP Pro, Office 2003 to OneNote etc etc http://www.microsoft.com/uk/partner/sales_and_marketing/actionpack/

Unsure if similar offer in US??

Hope this might help

---

Jonathan