<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; ">On Mr. Reynoldson's questions below and Mr. Lux' responses.<DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>It is advised to run four power line branches into your system room with quad "four hole" outlets on each branch (total of 16 power holes in 8 outlet sets in 4 utility boxes) and with individual circuit breakers on each branch ... Two runs on one phase (2 branches) and two runs on the other using 12 or 14 gauge wiring. There are several peculiarities about running multiple switching power supplies on a single 120 / 220 VAC branch (each system has one). It turns out that switching power supplies (as found in standard PC cases) can actually "sync up" and cause mysterious crashes, the switching power supplies placing a 400 Hertz demand wave on top of the 50 / 60 cycle power wave. By connecting half of your load to one phase (one of two branches) and half to the other phase on separate circuit breakers, the 400 Hertz switching demand load is "spread" over the two phases and your overall load is "balanced".<DIV><BR class="khtml-block-placeholder"></DIV><DIV>" ... What's the least expensive way of getting more electricity to the room? I can't do it myself (at least I think I can't). ..." ... Note: Canadian household power may be 220 VAC, split into two phases (in some provinces). Check before you buy anything or "plumb up" your power lines to the service panel.</DIV><BLOCKQUOTE type="cite"></BLOCKQUOTE><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Total operating load = 16 nodes X average 200 watts each = 3200+ watts. (This is a "running load", not a start up load which could easily exceed 5000 watts, even without hard drives and monitors.)</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Using four wiring branches, figure 1000 watts per branch = #14 AWG wiring. I would use 14 gauge "3-wire w/ground Romex" household wire (Red, Black, White & ground) making two home runs, two branches in each run, back to the main service panel ... connected to four, 15 Amp circuit breakers (one for each branch, two red wires, two black wires). Plug each pair of breakers into opposite phases in the main service panel to balancing the load as per above. (This will give you a modest expansion allowance up to maybe 20 to 24 nodes.) Note that 3-wire w/ground, 14 gauge wiring is commonly available and relatively inexpensive = here in California it is less than US$1.00 per foot and non-GFI, 15 Amp breakers are less than US$20.00 each.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV><SPAN class="Apple-style-span">Ground loops? Connect <SPAN class="Apple-style-span" style="text-decoration: underline;">all</SPAN> white (common wires) and <SPAN class="Apple-style-span" style="text-decoration: underline;">all</SPAN> ground wires in the main service panel to the central bus bar and make sure you have a very <SPAN class="Apple-style-span" style="text-decoration: underline;">good</SPAN> "local ground" in the main service panel. (Watch out! ... ZZZZZZTTT = tag, you've been hit! and are now headed for the hospital ... unless you turned off the main breaker before you opened the service panel.)</SPAN></DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>" ... Is there any chance of a fire hazzard if the breaker is overloaded or will the breaker just trip? ..." Yes! ... but if you have a qualified local electrician examine your work before you crank it up, there should be no problem found.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>" ... Would running the cluster diskless help much with power consumption? What about no CD and floppy drive? ..." ... Yes, but only to a limited extent. Trying to micro manage your power usage by removing drive mechanisms will be counter productive in the long run. Go ahead and leave the hard drives, etc., in the systems. The amount of power saved per node is less than 5% ... and being able to boot and run each system individually from its own hard drive will save you a world of time and possible frustration.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>" ... What are some good references to answer such questions? ..." ... make good friends with a qualified electrician. </DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Mr. Lux: " ... so, you can run all 5 boxes on the 15A circuit ..." ... Yes, of course. This may however stretch the limits of a many breakers. Five nodes X 200 watts per = 1000 watts total, minimum ... and assumes that the internal switching power supplies will never "sync up" making momentary power demands of 2000 or more watts every few cycles. I would not recommend more than four boxes per 15 Amp circuit breaker.</DIV><BLOCKQUOTE type="cite"></BLOCKQUOTE><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Mr. Lux" " ... Figure 200W/node (for lack of a better estimate) = 3200W. 3200W/110V = 29Amps 29A * 1.2 (design capacity factor) = branch circuit capacity of 34 A. ..." ... In Canada with 220 VAC power, a can of worms opens up ... dealing strictly with Watts and ignoring voltage considerations, you should not try to stress the circuit breakers beyond 50 to 60 % of rating = use a 2.00 "design capacity factor" and everything will run cool, system nodes, wiring and circuit breakers = greatly reduced fire hazards all around = greatly improved reliability of the whole system.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Mr. Lux: " ... 6) What's the least expensive way of getting more electricity to the room? ... Extension cords from another branch circuit <grin>. ..." ... Ah, yes, and a great big grin it is, too ... Kids, don't try this at home. Multiple extensions cords are absolutely forbidden in every server farm I have ever seen. Imaging that you are close to the end of your program run and you invite a few friends over to celebrate ... and one of them decides to play a little prank and pull an extension cord plug to make room for the wet bar ... Ah, yes ... big grins all around. Besided, I was lead to believe that fire hazards were of some modest concern = no extensions cords allowed.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV><BR class="khtml-block-placeholder"></DIV><BLOCKQUOTE type="cite"></BLOCKQUOTE><DIV>Ed Karns</DIV><DIV>FireWireStuff.com</DIV><DIV>(A member of IBEW, Journeyman & Commercial Electrical Contractor since 1975)</DIV><BLOCKQUOTE type="cite"></BLOCKQUOTE><DIV><BR class="khtml-block-placeholder"></DIV><DIV><BR class="khtml-block-placeholder"></DIV><BLOCKQUOTE type="cite"></BLOCKQUOTE><BLOCKQUOTE type="cite"></BLOCKQUOTE><BLOCKQUOTE type="cite"></BLOCKQUOTE><DIV><BR><DIV><DIV>On Dec 15, 2005, at 7:16 AM, <A href="mailto:beowulf-request@beowulf.org">beowulf-request@beowulf.org</A> wrote:</DIV><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>7. Estimating cluster power consumption (r reynoldson)</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN class="Apple-converted-space"> </SPAN>8. Re: Estimating cluster power consumption (Jim Lux)</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Message: 7</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Date: Wed, 14 Dec 2005 17:28:21 -0800 (PST)</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">From: r reynoldson <<A href="mailto:rreynoldson_ng_mail@yahoo.com">rreynoldson_ng_mail@yahoo.com</A>></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Subject: [Beowulf] Estimating cluster power consumption</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">To: <A href="mailto:beowulf@beowulf.org">beowulf@beowulf.org</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Message-ID: <<A href="mailto:20051215012821.15219.qmail@web54108.mail.yahoo.com">20051215012821.15219.qmail@web54108.mail.yahoo.com</A>></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Content-Type: text/plain; charset=iso-8859-1</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">... First I should say that I just have a little</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">experimental cluster (5 nodes including master) right</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">now, but have an opportunity to more than double this</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">size very cheaply. The compute nodes are a mixture of</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">366 - 450 Mhz boxes, 128 - 256 Mb ram. Currently they</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">have hard drives, but I'm seriously considering going</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">diskless (for the learning experience, amoung other</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">things). Also, the compute nodes are just boxes (no</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">monitor, keyboard, or mouse). The master node has an</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">1800 AMD cpu, 512 ram, and 60 Gb hard drive. ... A typical cluster</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">run could last anywhere from a day to several weeks</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">(possibly months?).</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">My house, which contains my cluster room, is rather</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">old. Looking at my breaker panel, it looks like my</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">cluster room shares a 15 amp breaker with an adjoining</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">room (sad, I know).</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Questions</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">1) About how many of the above mentioned nodes would I</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">be able to safely run?<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">2) Is there any chance of a fire hazzard if the</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">breaker is overloaded or will the breaker just trip?</DIV></BLOCKQUOTE><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">3) How does one estimate how many nodes they can</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">safely run?</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">4) Would running the cluster disk-less help much with</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">power consumption? What about no CD and floppy drive?</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">5) How much juice should be flowing to the room to run</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">a cluster of 16 such nodes?</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">6) What's the least expensive way of getting more</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">electricity to the room? I can't do it myself (at</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">least I think I can't). Which is the more desirable --</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">increasing the existing breaker amperage (if possible)</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">or getting a second breaker box (or replacing the</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">existing box with a bigger and better box)? The house</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">has copper wiring in the basement, which may affect</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">the cost (I also live in Canada too, eh!).</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">7) What are some good references to answer such</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">questions? I'd even spend money on a book, if it were</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">recommended highly enough.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Thanks in advance</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Rob</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; ">....</DIV></BLOCKQUOTE><BR><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">At 05:28 PM 12/14/2005, r reynoldson wrote: ( James Lux replying)</DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Questions</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">1) About how many of the above mentioned nodes would I</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">be able to safely run?</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">It's the rare single box that draws more than 200W (unless you've got quad<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">xeons or something) without the monitor. You generally don't want to load a<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">branch circuit to more than 80% of the rated capacity (0.8*15 = 12A, here)<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">12A is about 1200W (actually more like 1400, but fudging on the low side<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">here is a "good thing").. so, you can run all 5 boxes on the 15A<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">circuit.<SPAN class="Apple-converted-space"> </SPAN>(on a more practical note, I used to do this very thing, run 5<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">386,486, and Pentium 1 boxes on a single branch circuit in my apartmen, it<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">was the LaserJet III that caused the problems, especially if I decided to<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">vacuum)</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">2) Is there any chance of a fire hazzard if the</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">breaker is overloaded or will the breaker just trip?</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">The breaker "should" just trip on an overcurrent.<SPAN class="Apple-converted-space"> </SPAN>However, if the breaker<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">is a gazillion years old it might not.<SPAN class="Apple-converted-space"> </SPAN>Also, if the wall receptacle is old<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">and decrepit (most particularly, the wires on the back of the receptacle),<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">then you could be drawing a normal amount of current (i.e. 10A), and the<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">receptacle will still get hot enough to cause problems.<SPAN class="Apple-converted-space"> </SPAN>Unusual, but it<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">happens.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">3) How does one estimate how many nodes they can</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">safely run?</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Buy yourself a Kill-A-Watt for $30 and actually measure the power consumed.<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">(<A href="http://www.efi.org">http://www.efi.org</A>/ is one source, there are others)</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">4) Would running the cluster diskless help much with</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">power consumption? What about no CD and floppy drive?</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Every little bit helps</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">5) How much juice should be flowing to the room to run</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">a cluster of 16 such nodes?</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Figure 200W/node (for lack of a better estimate) = 3200W.<SPAN class="Apple-converted-space"> </SPAN>3200W/110V =<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">29Amps<SPAN class="Apple-converted-space"> </SPAN>29A * 1.2 (design capacity factor) = branch circuit capacity of 34 A.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">6) What's the least expensive way of getting more</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">electricity to the room?</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Extension cords from another branch circuit <grin>.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I can't do it myself (at</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">least I think I can't). Which is the more desirable --</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">increasing the existing breaker amperage (if possible)</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">or getting a second breaker box (or replacing the</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">existing box with a bigger and better box)? The house</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">has copper wiring in the basement, which may affect</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">the cost (I also live in Canada too, eh!).</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">A lot depends on what else in the house needs to be fixed when they get in<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">to make the changes.<SPAN class="Apple-converted-space"> </SPAN>Call your local electrician for an estimate, and they<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">can tell you what the tradeoffs are.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">7) What are some good references to answer such</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">questions? I'd even spend money on a book, if it were</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">recommended highly enough.</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Read RGBs online beowulf book at the duke brahma site.<SPAN class="Apple-converted-space"> </SPAN>He has a whole<SPAN class="Apple-converted-space"> </SPAN></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">chapter on infrastructure (power, HVAC, etc) issues.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Thanks in advance</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Rob</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">James Lux, P.E.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Spacecraft Radio Frequency Subsystems Group</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Flight Communications Systems Section</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Jet Propulsion Laboratory, Mail Stop 161-213</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">4800 Oak Grove Drive</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Pasadena CA 91109</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">tel: (818)354-2075</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">fax: (818)393-6875</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">------------------------------</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Beowulf mailing list</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="mailto:Beowulf@beowulf.org">Beowulf@beowulf.org</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="http://www.beowulf.org/mailman/listinfo/beowulf">http://www.beowulf.org/mailman/listinfo/beowulf</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">End of Beowulf Digest, Vol 22, Issue 19</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">***************************************</DIV> </BLOCKQUOTE></DIV><BR><DIV> <P style="margin: 0.0px 0.0px 0.0px 0.0px; font: 13.0px Lucida Grande">Ed Karns</P><P style="margin: 0.0px 0.0px 0.0px 0.0px; font: 13.0px Lucida Grande">IndustrialComponent.com</P><P style="margin: 0.0px 0.0px 0.0px 0.0px; font: 13.0px Lucida Grande">USBStuff / FireWireStuff / WireLessStuf / FiberStuf ... and much more</P><P style="margin: 0.0px 0.0px 0.0px 0.0px; font: 13.0px Lucida Grande; min-height: 16.0px"><BR></P><P style="margin: 0.0px 0.0px 0.0px 0.0px; font: 13.0px Lucida Grande"><A href="http://industrialcomponent.com/contact.html">http://industrialcomponent.com/contact.html</A></P><DIV><BR class="khtml-block-placeholder"></DIV> <BR class="Apple-interchange-newline"> </DIV><BR></DIV></DIV></DIV></BODY></HTML>