*** Updated... post 32 has instruction & picturres ***
Since lot of people have no way of load testing and safe way of doing it here is guide to components involved in making loadtester that is rather cheap. I found some components which are readily available online in US as well as easy to work with for it. I will update this with some pics as I get some time and full guide on how to make it with picture.
1) You need heating element. Lot of people go for power resistor. It is all good but what happens when you get condensation on it. Also, how well can you mount multiple of them correctly? Answer is.... not really as I've seen way too varying load figures from people.
Here is what I recommend. Cartridge heater.
McMaster.com carries one. Hightemp 1/4 diameter, 1-1/2" length is good choice. 3618K182 from mcmaster.com. It is about $20. You can get high temp sleeving on it, etc. (I suggest grabbing 200w one with stainless steel cable)
2) Copper block. About 2x2x1/2" is good choice. What you do is basiaclly drill this with same diamter as your cartridge diameter drill small hole for thermcouple in between surface and this hole for getting good idea on contact when you test. (no load same temp 150w load up to about 11c is good contact) DangerDen sells them for $5 a piece if you can't find one locally.
http://www.dangerdenstore.com/home.php?cat=49
3) AC cable to connect to cartridge. I am pretty sure most of you have them laying around.
4) Load varying station (Variac). I used to use variac from all electronics that was about $50. While it is very good, I found cheaper source for doing same thing. Basically rotary speed controller for your ac sources. You can use it just fine and it does work just same as variac. **UPDATE** stuff I got from harborfreight.com works just fine. http://da.harborfreight.com/cpisearc...3060&Submit=Go On sale around $10.
5) Way to know exact wattage used. I use kill-a-watt reader. Many places will have it from $20-35. E-bay is not a bad choice on this one if you can find reasonable shipping fee one which is always available from what i can see.
Total spent is less than $100 for very accurate load testing setup. I will write more about how to make one for those who just didn't get it later.
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