Power bricks getting hot at 220V - Page 1
Forum section: electronics / beginners

author: anvoice
author_rank: Frequent Contributor
timestamp: August 28, 2022, 06:41:23 pm
content: Some family members are staying in Europe (Netherlands) and complained that their chargers (which incidentally I bought) get uncomfortably hot when in use, which according to them didn't happen at 110V in the US. The chargers are 65W GaN units from a reputable manufacturer, clearly marked from 100 to 240V, so I was surprised. They have two nearly identical units which they claim both get hot, and I did ask them to try different outlets just in case: the problem persists. I'm trying to find a solution so they're not scared to leave the chargers on overnight or at full load.Does the efficiency decrease significantly at 220V (wouldn't think so since it's a switching psu, right?), enough for the charger to get significantly hotter than at 110V? If yes, I assume the problem can be mitigated by using a higher wattage charger, e.g. 100W. If not, the chargers may be faulty and I'd still need to advise them to purchase new units somewhere, but at least they could get away with a 65W unit.

author: Zero999
author_rank: Super Contributor
timestamp: August 28, 2022, 07:02:13 pm
content: That's all subjective and anecdotal.What was the ambient temperature?Did the power brick have adequate ventilation or was it burried under a load of stuff?Define too hot?What was the load?It's plausible it might be less efficient at 230V, than on 110V, but generally what happens is the switched mode controller reduces the duty cycle, so more current is drawn, at lower voltages, which would result in higher I2R losses. On the other hand, switching losses will increaser at higher input voltages.Proper measurements need to be taken, to isolate the other variables. You could try connecting a power brick up to 240V (use a cooker/clothes dryer/air conditioning socket) and measure the temperature, to see if it heats up as much as when run on 110V.

author: Benta
author_rank: Super Contributor
timestamp: August 28, 2022, 07:29:47 pm
content: I have doubts about your "reputable supplier" claim, since you don't wany to mention the name.My HP/Compaq 90 W 1/4 bricks get lukewarm at most, independent of input voltage.

author: anvoice
author_rank: Frequent Contributor
timestamp: August 28, 2022, 07:48:46 pm
content: Quote from: Zero999 on August 28, 2022, 07:02:13 pmAsking them to do extensive testing is probably a bit too much... so I'm guessing it should be a wash? They don't have a thermometer to measure the exact temperature.Quote from: Benta on August 28, 2022, 07:29:47 pmI didn't want to advertiseBaseus is a decent manufacturer from what I know, bought on Amazon. Perhaps I should tell them to buy a 100W unit on the Netherlands Amazon site. At least that way they have some recourse if it doesn't work properly.

author: Benta
author_rank: Super Contributor
timestamp: August 28, 2022, 07:56:46 pm
content: I stand corrected, Baseus is indeed reputable.But the question still remains: how hot?If your friends/relatives can hold the charger in their hand when running, it's OK.

author: Zero999
author_rank: Super Contributor
timestamp: August 28, 2022, 09:17:43 pm
content: Quote from: anvoice on August 28, 2022, 07:48:46 pmWhy don't you do the testing yourself? That way you can ensure the only variable is the voltage. As I said in my previous post, there are high power sockets which will give you 240V.

author: Benta
author_rank: Super Contributor
timestamp: August 28, 2022, 09:45:24 pm
content: Quote from: Zero999 on August 28, 2022, 09:17:43 pmWell, as the chargers are in Europe and the OP is in the US, the temperature sensor leads as well as her/his arms need to be pretty long...

author: anvoice
author_rank: Frequent Contributor
timestamp: August 28, 2022, 10:04:34 pm
content: Quote from: Benta on August 28, 2022, 09:45:24 pmI think the suggestion may be to test another GaN charger (which I do have, albeit not the same kind) on both 240V and 110V here in the US and see how hot it gets. Which would at least tell me whether it is normal or not for such a charger to get hotter on a higher voltage. I don't have very good access to my dryer's socket unfortunately, but I think it's a nice suggestion.

author: anvoice
author_rank: Frequent Contributor
timestamp: August 28, 2022, 10:05:56 pm
content: Quote from: Benta on August 28, 2022, 07:56:46 pmThanks, good to know! I'll ask them to try that this evening, as they're asleep now.

author: tpowell1830
author_rank: Frequent Contributor
timestamp: August 28, 2022, 10:27:57 pm
content: Quote from: anvoice on August 28, 2022, 06:41:23 pmThe units are rated at 110 volts at 60 Hz.? The standard U.S. power mains are 240 volts 60 Hz. split phase, giving 2 - 120 volts mains (with neutral) and most of Europe mains are 230 volts 50 Hz. The frequency difference is a factor as well, if the power supply is not rated at 50 Hz.But I agree with some above, that if they can be held in the hand without discomfort, then it is not necessarily over heating.

author: tooki
author_rank: Super Contributor
timestamp: August 28, 2022, 10:38:56 pm
content: Is their European lodging air conditioned? If not, then the difference in ambient temperature compared to a typical (i.e. very cold) American building could easily explain a difference in charger temperature.

author: tooki
author_rank: Super Contributor
timestamp: August 28, 2022, 10:41:25 pm
content: Quote from: tpowell1830 on August 28, 2022, 10:27:57 pmSince the first thing that happens in a switching power supply is to rectify the incoming AC to DC and smooth it with a capacitor, the line frequency is essentially irrelevant.

author: nightfire
author_rank: Frequent Contributor
timestamp: August 28, 2022, 10:48:34 pm
content: Question here: At which ambient temperature were they used? Here in western Europe we had the last weeks about 30+ deg C, so it was very hot, meaning that not much heat dissipation from the chargers to ambient could have taken place.

author: AndyBeez
author_rank: Frequent Contributor
timestamp: August 28, 2022, 11:11:29 pm
content: Assuming these bricks are plug-in units...Do the power bricks get hot in another power socket? Are they connected using a travel adapter (US to NED)? I ask as sometimes the plug pins can make only partial contact with the socket tabs, producing unexpected heating due to the increased resistance.Without a tear down, you will no idea of where the issue really is.

author: anvoice
author_rank: Frequent Contributor
timestamp: August 29, 2022, 12:12:45 am
content: Quote from: tpowell1830 on August 28, 2022, 10:27:57 pmIt's rated at 50Hz, so I don't think that's the issue.Quote from: tooki on August 28, 2022, 10:38:56 pmMight be on to something. In the US it's about 25C in the house, whereas it was >30 with no AC where they are staying now.Quote from: nightfire on August 28, 2022, 10:48:34 pmYou may well be right, as tooki also suggested.Quote from: AndyBeez on August 28, 2022, 11:11:29 pmI did ask them to switch power sockets, and they said the bricks still get hot. They do use a travel adapter: I'll ask them to take it out and (carefully) check whether the prongs get hot. Thanks for the suggestion!