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hello!
There seems to be so many different types of load testers, and so many types of ways to read the wattage. I have seen some very unique ones (piotres:up: )
So if you want, just post picture and explain how well your results have been. Also what type helps:up:
Regards
Study up on "Ohms Law" ;)
P=VI helps too. Can't calculate power without that. ;)
Actually you only need any 2 values to calculate the other 2 values using ohms law.Values are:Quote:
Originally Posted by Polizei
"P" power(wattage) "E" (voltage) "I" (amperage) "R" (resistance)
The thread is post your load testers.
I don't have one yet. I need to get my copper block back from my buddy.
We have some discussion here in Germany/Austria going on about loadtesters at the moment. Many use 230V heating cartridges with a dimmer to adjust power and a kind of a kill-a-watt meter to show the used power. This is, in my humble opinion, often very far off from the real power consumed. I had 3 different power meters like a kill-a-watt here and they were often off by 40%. The reason the leading edge of the dimmer which makes the voltage so irregular and hard to measure the effective voltage.
I prefer a DC load tester which has 2 resistors 1Ohm/50W in series and is hooked up to an adjustable DC power supply 30V/30A. Also I mounted 2 sense lines to measure the exact voltage drop over the resistors without the connection lines.
Regards,
Philipp
Probably the best solution IMO, PhilippF.
wow very profesional phillip!
ill post mine in a few. im going to send ya a PM.
Mine is very similar to Jin's guide. 250 watt cartridge heater (next time will use two 200 or 150 watt ones), and a 128c thermal fuse placed to far from the load tester.(better then starting a fire i guess)
http://img401.imageshack.us/img401/9...tester2oo3.jpg
http://img98.imageshack.us/img98/475...luminumwn8.jpg
Rear- cut square in holdown and milled out load tester so it would stick.
http://img98.imageshack.us/img98/6573/finished2yx4.jpg
regards
:spam:Quote:
Originally Posted by wdrzal
:spam:Quote:
Originally Posted by Polizei
:spam:Quote:
Originally Posted by wdrzal
:spam:Quote:
Originally Posted by [XC] 2long4u
:spam:Quote:
Originally Posted by DagoDuck
My load tester.
250w heater cartridge inserted into Cu block.
Adjustment by 20-450w incandescent light dimmer between 70 and 230w.
Fluke Ammeter in line to read current, I have a table of amperage readings I work from to calculate wattage in 25w increments.
http://justchillin.co.nz/pics/2007%2...ck%20honed.jpg
http://justchillin.co.nz/pics/2007%2...ck%20wired.jpg
http://justchillin.co.nz/pics/2007%2...20@%20231w.jpg
http://justchillin.co.nz/pics/2007%2...%20@%2075w.jpg
Just took a photo of it strapped to the cascade.
http://justchillin.co.nz/pics/Tools/...d%20tester.jpg
Philippf - what Resistors OHM - do you use (i saw TWO resistors)
How many Watt each ???
Also - is a 226W of TEC can be used somehow as a Load Tester ??
TEC is more expensive and less useful than resistors or cartridge heaters.
These two resistors are 1 Ohm each and are put in series. Euach one is a 50W type, which of course is meant for room temp. 350W is no problem at -25C.
Regards,
Philipp
Duniek, you can adjust the power of this one?
What do you use to know the power? Some kill-a-watt meter?
n3ro:
you put it straight to your wallsocket, to know the power, use either a kill-a-watt or measure resistance.
I use 50W resistors but dunno what exactly resistanceQuote:
Originally Posted by N3RO
but its good for 220V
if i have 230V then i have 235W heat on it
Mine - unique ? :eek:
I think nothing more simple than mine loadtesters ;-) .
http://www.members.lycos.co.uk/piotres2/majd/33.jpg
260W dummy made of 3x 50W resistors - I know they're overloaded much but they work without problems with sub-zero temperatures :D . 230V powered . Alu plate 10 mm thick .
http://www.members.lycos.co.uk/piotres2/majd/34.jpg
225W dummy made of 4x 50W resistors .230V powered . Alu plate 10 mm thick . That box is "cut-off" which should turn off dummy when I forget to switch it off after test and dummy is going to be very hot - it should turn off 230V when alu plate reach 70*C, unlucily it turn if off also when alu is very cold - I mean test on -100C evap cascade, it turns off power too :mad: . When I test SS with around -50C it's OK, safety cut-off can be turned ON, it not cut in such sub-zero temps . That's why I make ON/OFF switch on that safety device :) .
Thanks
Regards
Peter
here some pics of what i use it is 2-150 watt heater cartridges in a copper block that is 3/4" thick x 2" x2" and a k-type temp probe and i hook it all up to a kill-a-watt meter here are some pics
Nice work boys :D
Love it when you can go above the normal 235 or 250 watt :D
3x 75 ohms, With my 0-265v variac I have a varible load tester from 0-312w.
http://img503.imageshack.us/img503/9...sistorskw2.jpg
http://img503.imageshack.us/img503/7...loadfarxu5.jpg
http://img266.imageshack.us/img266/2538/dsc01493ud3.jpg
The photos are great but - I'm not sure i understood this Load !
Can someone Post an Electrical wiring Scheme so i will understand better
How eXACKLY Did you Connected these ressistors to a 230V ???
I want to use this to Measure my Single Stage Power .
äh i dont think that there is ver much to explain...
~ o------[[[[[[[]]]]]]]]]------o ~
a resistor betwenn the two "poles" (phase and neutral).
Or if needed more than one resistor, then in parallel or in series
Take 2 resistors, wire them in series and connect them directly to your 230V. THe formula to calculate the power is P=(u²)/rQuote:
Originally Posted by lior307
The resistance of resistors in serie's = R[sub]t[sub]=R1+R2+etc.
If you use 2 100ohm resistors on 230V
Rt=100+100 = 200
P=(230²)/200, P=265W
If you want to calculate wich resistance you need for 100W the formula is R=U²/P
R=230²/100 R=530OHM
Hello Peter, how much Ohms does each Resistor have and did you wire them in series or in parallel?Quote:
Originally Posted by piotres
in series between active and neutral, ground the load test as well with the earth wire.Quote:
Originally Posted by lior307
http://img503.imageshack.us/img503/7...loadfarxu5.jpg
In series, but I don't remeber resistance :( .Quote:
Originally Posted by godmod
Here is mine. I bought the block and heater cartridges from DetroitAC. The block is 1.5x1.5x.75 inches. There are 2 3/8 150w heater cartridges. I have a variac to control the voltage applied.
My initial pics.
2 HC 75w at 220v
variac 2kva
need to find a copper bar....
sorry revival this post but just finished mine :
heres mine :)
one 300w heater cart with 400w dimmer
oh and armaflex and heat loader = bad! fiberglass ftw
http://i90.photobucket.com/albums/k2...c/Image008.jpg
http://i90.photobucket.com/albums/k2...arlos/Imag.jpg
http://i90.photobucket.com/albums/k2...s/Image001.jpg
http://i90.photobucket.com/albums/k2...s/Image002.jpg
in use
http://i90.photobucket.com/albums/k2...o/Image002.jpg
nice guys!
Ill repost mine soon, i remade mine so ill post up some pics :)
Hey that looks pretty sweet Carlos. Where did you get that fiberglass and how do you have it wrapped together (like glue, staples, rubberbands, etc)
lol Teyber are you communist now?
hey the fiber glass came from work lucklly they make log burners and theres lost of f/g in the door seal and boiler part so was easy to come byQuote:
Originally Posted by sjg0
and its all held together with wynn's industrial strenth super glue :)
My load tester uses two 150W cartidge heaters in a copper block, bores cut with a boring head on the mill so they are nice and tight clearance.
I milled the die shape of an Intel quad into the top of the block. For a while I was using TIM between the simulated dies and the top an Athlon proc. Then I switched to a LGA775 processor lid and soldered it to the dies with a very thin layer of solder. It's hard to see but there is an air gap around the perimeter of the IHS and only the dies make contact with the IHS.
Stancor thermal switch mounted to back of the block. It saved my load tester from a meltdown about two weeks after I installed it :up:
CNC'd Delrin flange with a stepped square cutout for the copper block to sit in. When I want a very accurate test I just wrap the whole thing in Armaflex.
reed said it was good DetroitAC but its very very impressive to see it :)Quote:
Originally Posted by DetroitAC
DetroitAC- very IMPRESSIVE :eek:. You have Your own machine park with all CNC millers I guess?
hes got an cnc converted rf 45 if i remember :up:Quote:
Originally Posted by piotres
What thermal switch are you using DetroitAC?
This one --> Stancor
@Piotres, Yes I have A large conversion bed mill and a small mill with a high speed spindle. Most of the work was on the bed mill, but the die sim machining was done on the small one.
DetroitAC do you recall the make and model of those 150 watt cartridges?Quote:
Originally Posted by DetroitAC
They look like the ones from McMaster:Quote:
Originally Posted by sdumper
http://www.mcmaster.com/#cartridge-heaters
Thanks Jack.
I need a replacement and didnt want to get the wrong size...but I heard someone say once that's what a tape measure is for :)
http://www.tempco.com/Cartridge_Heaters/HD_Main.htm
Find what you want by dia.:up:
This one works pretty good-voltage, current, block temp and evap temp
http://img36.imageshack.us/img36/316...054640x480.jpg
Great Pics !!!
I also would like to build a Load Tester of 300W But ,
1. Where can i find Copper Plate and Two Heaters of 150W - For 230V
(Two 150W = 300W) also what Size should i ask for heaters ?
I need Stores that can ship to Europe .
That is absolutely amazing!!!!!Quote:
Originally Posted by gosmeyer
Quote:
Originally Posted by lior307
For the copper plate you can buy from one of the members of the Forum or from the local market have.
HEATER CARTRIDGE @ 6.5X50MM, 160W X 2
http://uk.farnell.com/redring/120006...60w/dp/8244456
OR
6.5X40MM, 100W X 3
http://uk.farnell.com/jsp/search/pro...sp?SKU=8244430
Also you will need to thermal switch :
http://uk.farnell.com/jsp/search/pro...jsp?SKU=491524
OR
http://uk.farnell.com/jsp/search/pro...jsp?SKU=732606
Good luck,
Copper...Quote:
Originally Posted by lior307
http://www.regis.demon.co.uk/mallard/catalogue.pdf
Heaters 300watt 230v...
http://uk.rs-online.com/web/search/s...duct&R=3761887
Hope that helps mate :)
My load tester :
HEATER CARTRIDGE @ 100W X 3
Thermal switch
Copper Plate @ 50mm x 51mm / 16mm Thickness
Transformer Variable
http://i275.photobucket.com/albums/j...d_tester_1.jpg
http://i275.photobucket.com/albums/j...d_tester_5.jpg
http://i275.photobucket.com/albums/j...d_tester_2.jpg
http://i275.photobucket.com/albums/j...d_tester_3.jpg
http://i275.photobucket.com/albums/j...d_tester_4.jpg
Here are my load testers:
http://img18.imageshack.us/img18/1692/p1100250a.jpg
http://img14.imageshack.us/img14/2833/p1100252u.jpg
Left one - was used as 150W connected to 150VAC 12V transformer. But could be more when using 15-16V power supply (240-270W). Two 0.47R resistors connected in series.
Right - my latest build :up: Four 220R resistors, connect in series and parallel, which gives 220R total resistance. 240W, when using 230V.
Still a work in progress because real work gets in the way :(
http://www.brittech.co.uk/testdie.jpg
The actual heater core hand made niachrome around ceramic insulator heating a copper core and outer copper shell and wrapped in fiberglass and wiremesh heatshield to make sure all the heat goes to the target.
Heater core is 2ohm and built originally for a 12/28v 400Watt power supply unlucky for me company burn't down before I purchased PSU.
Ended up with old HP one in the pick which gives me upto 800Watts
Engineered for all Air cooled heatsinks / watercooling blocks & phase change.
I'll get it finished one day.
I can't tell for sure but you should measure the load between the catridges and the Variac. If you measure between the variac and the wall recepticle your reading will be skewed by the ineffency of the transformer.
PWM: It doesn't inspire confidence if the manufacturer of the heater burnt down. :P
wdrzal is correct regarding the measurement position, the only case when that is wrong is when using an in-line energy meter as the lower supply voltage may cause incorrect readings or no readings at all.
Quote:
Originally Posted by yngndrw
My orginal statement in above post is never wrong,:) If you using a inline meter that can't read the voltages & amps or wattage on the secondary side of your transformer for any reason......Get a meter that can.:up:
Ps: you need test equiptment you trust that stays in calibration.
Walt can you show an example...even a simple drawing would be helpful.Quote:
Originally Posted by wdrzal
Going to make this load tester in ~ 1 week. I already have 3 of the pieces finished. just the easiest piece, the plastic piece, needs to be machined.
Here are renders-
http://i198.photobucket.com/albums/a...oadtester1.jpg
http://i198.photobucket.com/albums/a...oadtester2.jpg
Looks good, maybe I'll replace my old block when that's done! I just got a new purdy variac.
Scott I didn't see your question until this thread was bumped today.Quote:
Originally Posted by sdumper
If you plug your watt meter into a wall receptacle and then plug your variac (transformer) into it, your watt meter will read total current,including the inefficiency of the transformer. Since transformers are not 100% efficient and their efficiency varies ,your reading will be higher than the actual load than if you measure current between transformer & load cell.
For a higher degree of accuracy measure the current between the transformer and load tester.
Your using resistive heating cartridges ,the electricity is converted to heat @ ~99.98% efficiency, so call it 100% unless you care about a small fraction of a watt error............
You will get a much more accurate reading of actual heat being produced if you measure after transformer.
Yep, that is true.
I tested this a while back, I'm sure it's still up in some thread.
At 300W at a load tester, post Variac I was reading 294W, with 300W at the wall.
New parts for load testers: :)
Heater with K-type thermal probe integrated. 0 - 250W
http://ld-phasechange.com/images/load_tester/2.JPG
http://ld-phasechange.com/images/load_tester/3.JPG
Normal: 0 - 315W and 0 - 400W.
http://ld-phasechange.com/images/load_tester/4.JPG
Kind Regards
Fantastic :eek: I do want one! :D
Thanks Walt!!
Off Topic:
Hey Tiborrr good to see you around again! I miss reading your build threads.
Hey buddy! Yeah, the six-month mandatory active full-time job in the industry/engineering bureau is taking it's toll. Tommorrow's the last day before a month long break. I'll commit it to the upcoming 2-stage auto-cascade build :)
Best Regards to my fellow XS buddies,
Niko :up: