Soldering Iron Station True Power Ratings - Page 1
Forum section: electronics / general

author: MrAl
author_rank: Super Contributor
timestamp: June 22, 2015, 01:19:54 pm
content: Hello there,An interesting blog would be to see a video of some testing of some of the soldering stations being sold in places like Amazon and eBay. These could be with or without the heat gun.The main issue is the power rating of the irons themselves dont seem to be up to what they are advertised at, for some models. i had the opportunity to test two of these and found them both lacking by a large percentage. In fact, both were rated for 60 watts on the web advertisement and both were only 36 watts actual power delivered to the heating element in the iron itself. That's a huge difference. I bought one myself and was disappointed because i thought i was getting a much higher powered iron. You can still use them, but not if you were expecting a 60 watt iron.I enjoy Dave's videos and other people i know do too, and it would be very interesting to hear his take on this matter.Take care,Al

author: timofonic
author_rank: Frequent Contributor
timestamp: June 22, 2015, 04:15:43 pm
content: I'm a newbie, but this reminds me of RMS and speakers.Seriously...Aren't there a regulated, standard and scientific way of measuring and forbid these damn lies?? ? It surprises me this crap is still happening these days.

author: nanofrog
author_rank: Super Contributor
timestamp: June 23, 2015, 06:11:54 am
content: They may be substituting VA for Watts, which only works at 100% efficiency (linear PSU's are only ~60% efficient). Assuming the same testing conditions for all stations (since no particulars are given), and assuming the specified value is in fact VA, then 60VA*.60 = 36W, which happens to match up with what you're seeing (the transformer is one of the most expensive components in it, so is a big target for cutting corners as a means of cutting costs).___________________FWIW, even if you have multiple irons consuming 36W to run the heating element, there's still variations in the efficiency of how well that heat is transferred to the joint. So there's more to a station's performance than just power consumption. This is why you see an improvement in performance between traditional tips that slide over or butt against a heating element vs. a cartridge tip (heating element + sensor are embedded into the tip itself).

author: BradC
author_rank: Super Contributor
timestamp: June 23, 2015, 06:41:20 am
content: Quote from: nanofrog on June 23, 2015, 06:11:54 amI think you're confused. VA vs Watts is a power factor issue, and the power factor of a resistive heater is 1. Even with a small shift caused by the transformer its going to be so close to 1 as to not matter. If the iron is only drawing 36W that's because the heater is only rated for 36W, and has absolutely nothing to do with "inefficiencies of linear PSU's" or any other incorrect or fabricated excuses. BTW, if your 60W iron is only generating 36W of heat, and the rest disappears in the "efficiency of the PSU", then your PSU should be pumping out 24W of heat and you'd know all about that pretty quickly.

author: MrAl
author_rank: Super Contributor
timestamp: June 23, 2015, 10:05:13 pm
content: Hi,Very well said.In addition, the heat transferred to the joint has nothing to do with the power rating either. If you have a 50 watt that poorly transfers heat, you can have a 100 watt that poorly transfers heat, etc., but the heating element will really be 50 and 100 watts respectively, regardless of how it transfers heat.The rule here is we dont say something doesnt work because there are ghost variables that we cant explain. If we cant explain them then they cant explain them either.When it comes to heating, it's one of the simplest concepts on earth. If you have 20 watts of heating you have 20 watts of heating, and if you have 50 watts of heating you have 50 watts of heating power, period. There's no wiggle room here especially since soldering irons have been given ratings since the stone age.I know people sometimes jump to the "possible variables" when something doesnt work right, but the reason we are here today is because we want to explain all the variables and come to a conclusion. For this we can, and state that the irons are being over rated by the sellers.Also, and this really nails it, some irons sold as 60 watts come with elements stamped "50 watt" right on the element itself. Now that wouldnt be too bad i guess, 50 vs 60, but unfortunately that "50 watts" is also untrue because the element is still only 36 watts !Maybe the better manufacturers put out some quality stuff with the right ratings, but some of these knock offs clearly dont. I havent been able to test any really good units unfortunately, only some cheaper ones. One was about $150 and the other was about 70 or 80 dollars (USD).