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Electricity Safety - Running your Boinc Cruncher
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![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
Over in the "BitCoin" thread an interesting topic came up. How to run your Boinc Machine(s) safely given you may have higher than average power draws by crunching multiple GPUs? A reason I am interested in this topic is I want to be able to safely experiment with running up to 18 GPUs on a Mining Rig MB. I live in a mobile home with 2 20 Amp circuits in the Kitchen and assorted 15 Amp circuits about the house. One of my 20 Amp circuits is completely unloaded (except for running the Boinc system on it). The other also powers my Refrigerator/Microwave. This Mining MB (MSI B360-F Pro) allows for direct control of up to 5 different PSU's. So the theory is plugging each PSU into a separate breaker circuit. The cropper is I need a safe extension cord and surge protector combination. As an electrician pointed out. You can't go cheap on this without burning down your house. I have a combination Kitchen and Living Room and the Mining Rack is now living at the border of the living room/kitchen. I need two surge protectors rated at 20 Amps (eg. 120 X 20 = ~2,400 watts?) and two extension cords of the same rating. 1 should be about 25' long. I think the other can be 10-15' long. My other choice(s) include: 1) Don't run so many video cards. 2) Pay an electrician to run dedicated circuits to where I need them. 3) Drop out of Boinc/Seti@Home. I am confident option #3 will never fly. I have been crunching since pre-BOINC days starting with a Windows screen saver. #2 Depends on finishing new STEM training and successfully getting hired at a high paying job (I'm over 40 [aka: Semi-Retired] so I have that issue). #1 is my fall back position. I am running 8 GPUs now. So what do you think are good brands/models of 20 Amp extension cords and surge protectors? I am assuming I will have to special order because these are "outlier" load levels and my local hardware store just doesn't carry stuff that heavy (mostly). Tom A proud member of the OFA (Old Farts Association). |
![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
Eventually, I will need to consider getting a UPS or combo of UPS's but first I have to prove that a very high draw system is feasible and safe. A proud member of the OFA (Old Farts Association). |
![]() ![]() ![]() Send message Joined: 29 Apr 01 Posts: 13164 Credit: 1,160,866,277 RAC: 1,873 ![]() ![]() |
If I needed what you propose, I would just buy some bulk wire, plugs and make the cable myself. Have done so many times. Made a 15 foot extension cord for the power amp for the stereo (2000W). Made an extension cord (30 ft.) for the 240V wire welder in the garage. Go down to your local hardware store and buy bulk SO 12/3 or 10/3 cable off the cable spool rack and good quality plugs and wire them yourself. Seti@Home classic workunits:20,676 CPU time:74,226 hours ![]() ![]() A proud member of the OFA (Old Farts Association) |
![]() ![]() ![]() Send message Joined: 27 May 99 Posts: 309 Credit: 70,759,933 RAC: 3 ![]() |
With 1600watt power supply at full load: 115v need 1600/115 = 14 amps and 12 gauge recommended as extension 230v need only 7 amps can get by easily with 14 gauge stranded on a long run or 16 gauge on shorter run not exactly wiki but the amp ratings below agree with published standards https://www.askthebuilder.com/extension-cords-size-chart/ 16-Gauge Cords: Any 16-gauge cord between 0 and 100 feet long will adequately handle tool loads up to 10 amps. 14-Gauge Cords: Any 14-gauge cord between 0 and 50 feet long will adequately handle loads between 10 and 15 amps. 12-Gauge Cords: If your tool load is between 10 and 15 amps and the length of the cord is 50 to 100 feet, you need a 12-gauge cord to safely power any tool. Have your brother wire up an extension from dryer to rig and use Tuesday's SETI down time for dryer usage. If using NEMA 5-15 (North American & Japan) for the "end" near the rig may want to tape on a warning "DO NOT CONNECT 115V APPLIANCES" UPS is only good for keeping internet modem and cable tv modem and "channels lists" from being reset during power outage. My brother has a "Fox Blocker" but he didn't get a UPS and occasionally his day is ruined when he accidently watches Fox News. I told him that a %25 means only 1 out of 4 democrats want Bernie but he thinks Bernie is the front runner. [EDIT] - CORRECTION: 1600full load is what is delivered, power supply will consume more, maybe 2000 but the 12,14, 16 is still valid assumption |
rob smith ![]() ![]() ![]() Send message Joined: 7 Mar 03 Posts: 22652 Credit: 416,307,556 RAC: 380 ![]() ![]() |
A hint - When working out the expected current on a circuit from the load power use the lower limit of the supply voltage, not the nominal or maximum. This will give yo a bit of headroom. Over the years I've seen too many breakers & fuses pop or cables melt when they "should have coped", but in reality the supply voltage has been at the low end of the tolerance, not the assumed high end. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
If I needed what you propose, I would just buy some bulk wire, plugs and make the cable myself. Have done so many times. Made a 15 foot extension cord for the power amp for the stereo (2000W). Made an extension cord (30 ft.) for the 240V wire welder in the garage. Go down to your local hardware store and buy bulk SO 12/3 or 10/3 cable off the cable spool rack and good quality plugs and wire them yourself. I think my brother and nephew have been doing that. Maybe I will see how much a "custom" job would cost :) Tom A proud member of the OFA (Old Farts Association). |
![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
With 1600watt power supply at full load: I end up using the Dryer more often than once a week. So I would problably have to take the rig down more often. I will ponder it. But simple is best. And your idea maybe a solution for the future (next week?) anyway, thank for offering me information and a possible solution. Tom A proud member of the OFA (Old Farts Association). |
![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
A hint - When working out the expected current on a circuit from the load power use the lower limit of the supply voltage, not the nominal or maximum. This will give yo a bit of headroom. Over the years I've seen too many breakers & fuses pop or cables melt when they "should have coped", but in reality the supply voltage has been at the low end of the tolerance, not the assumed high end. I would rather have the breaker trip than the extension melt/smoke etc. But your point is comes down to is my project may not be do able in my current living circumstances. Tom A proud member of the OFA (Old Farts Association). |
![]() ![]() ![]() Send message Joined: 29 Apr 01 Posts: 13164 Credit: 1,160,866,277 RAC: 1,873 ![]() ![]() |
You should stay within the 80% rating of the breaker. Also if you have a temperature IR gun, shoot the breaker in the panel. You should try and keep the breaker below 90° F. or 50° C. above ambient temps. Anything higher says you are pulling more current through the circuit than you should be. The load should be reduced. Seti@Home classic workunits:20,676 CPU time:74,226 hours ![]() ![]() A proud member of the OFA (Old Farts Association) |
![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
You should stay within the 80% rating of the breaker. Also if you have a temperature IR gun, shoot the breaker in the panel. You should try and keep the breaker below 90° F. or 50° C. above ambient temps. So it sounds like 16 Amps maximum on a 20 Amp circuit. I will look around for an IR gun, I have been using finger tips :) Tom A proud member of the OFA (Old Farts Association). |
![]() ![]() ![]() Send message Joined: 29 Apr 01 Posts: 13164 Credit: 1,160,866,277 RAC: 1,873 ![]() ![]() |
Wait for a IR gun to be on sale or with a coupon at Harbor Freight. https://www.harborfreight.com/search?q=infrared+temp+gun I think I picked mine up for under $10. Seti@Home classic workunits:20,676 CPU time:74,226 hours ![]() ![]() A proud member of the OFA (Old Farts Association) |
rob smith ![]() ![]() ![]() Send message Joined: 7 Mar 03 Posts: 22652 Credit: 416,307,556 RAC: 380 ![]() ![]() |
An IR gun is on my most wanted list -It would be really great to know where that aroma of hot wires and fittings was coming from before the loss of the enclosed smoke. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
Wait for a IR gun to be on sale or with a coupon at Harbor Freight. My town just picked up a harbor freight store. +1 Tom A proud member of the OFA (Old Farts Association). |
![]() ![]() ![]() Send message Joined: 29 Apr 01 Posts: 13164 Credit: 1,160,866,277 RAC: 1,873 ![]() ![]() |
If you go into HB, at least pickup a cheap multimeter for $6 so you can measure voltage. Frequently on sale also for as little as $3. https://www.harborfreight.com/search?q=multimeter Seti@Home classic workunits:20,676 CPU time:74,226 hours ![]() ![]() A proud member of the OFA (Old Farts Association) |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13882 Credit: 208,696,464 RAC: 304 ![]() ![]() |
If you go into HB, at least pickup a cheap multimeter for $6 so you can measure voltage. Frequently on sale also for as little as $3.I hate cheap multimeters with a passion. Poor accuracy (even at lower voltages) and slow sample/response times make using them an exercise in frustration. I'd suggest a mid range unit, even if only for occasional work. Grant Darwin NT |
![]() ![]() ![]() Send message Joined: 29 Apr 01 Posts: 13164 Credit: 1,160,866,277 RAC: 1,873 ![]() ![]() |
If you go into HB, at least pickup a cheap multimeter for $6 so you can measure voltage. Frequently on sale also for as little as $3.I hate cheap multimeters with a passion. Ha ha LOL. I was just trying to present a "no reason - NOT to own a multimeter" in everyone's toolbox. I pull out the cheap HB multimeter 10X times a day more often compared to my Fluke Model 87 DVM. The cheap HB one is totally sufficient for measuring a AA battery voltage state or whether you have 115VAC on a electrical socket. Just as fast as pulling out a test lamp to plug in which only shows some AC voltage sufficient to heat up a filament. If I want to measure something more critical I will get out my Fluke 87 or my Scopemeter handheld. Seti@Home classic workunits:20,676 CPU time:74,226 hours ![]() ![]() A proud member of the OFA (Old Farts Association) |
![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
If you go into HB, at least pickup a cheap multimeter for $6 so you can measure voltage. Frequently on sale also for as little as $3. I think I have a cheapo from Radio Shack or someplace. I use it for continuity checking and other "high end" tasks :) Tom A proud member of the OFA (Old Farts Association). |
kittyman ![]() ![]() ![]() ![]() Send message Joined: 9 Jul 00 Posts: 51502 Credit: 1,018,363,574 RAC: 1,004 ![]() ![]() |
Might I chime in with a bit of experience on the subject? I went through all of this back when I was running 9 rather hevi-duty crunching rigs. I burnt up power strips and wall outlets. Lucky for me, I didn't burn the shack down in the process. I ended up running a new 240v feeder from the mains breaker box to a subfeed box in my living room and then branched off a number of individually breaker protected 120v 15a drops from that to safely feed my crunchers. Please do not underestimate the risk of overloading your existing wiring if it is not sufficient to supply the load of computers with a very high power draw. Know your house's wiring and check power draw with a killawatt meter if you are in doubt. Searching the stars for other life is not a wise thing if you burn up your life on this planet. I learned this in time to prevent a disaster. I hope you do as well. Meow. "Time is simply the mechanism that keeps everything from happening all at once." ![]() |
![]() Send message Joined: 28 Nov 02 Posts: 5126 Credit: 276,046,078 RAC: 462 ![]() |
Might I chime in with a bit of experience on the subject? Welcome back and to the conversation! We missed you. Tom A proud member of the OFA (Old Farts Association). |
kittyman ![]() ![]() ![]() ![]() Send message Joined: 9 Jul 00 Posts: 51502 Credit: 1,018,363,574 RAC: 1,004 ![]() ![]() |
Thank you very much. Glad to be back. Meow! "Time is simply the mechanism that keeps everything from happening all at once." ![]() |
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