When having 230V what is the best choice, 220V or 240V?  - Page 1
Forum section: electronics / general

author: Swake
author_rank: Frequent Contributor
timestamp: November 18, 2023, 11:10:37 am
content: Hi,A lot of gear (especially HP devices) can be configured for 220V or 240V input. in this case what is the best choice for the 230V countries?

author: AndersJ
author_rank: Frequent Contributor
timestamp: November 18, 2023, 11:58:55 am
content: If the device has a linear power supplyit will run slightly cooler if set to 240V.

author: EPAIII
author_rank: Super Contributor
timestamp: November 19, 2023, 07:30:16 am
content: 220, 230, and 240 are for all intents and purposes THE SAME THING. It is called TOLERANCES.Here in the US the nominal household Voltage is 115 or 117 VAC. But when we talk about the actual Voltage that is delivered to every house it is actually twice that. And two times 115 V is 230 V. But does anyone ever say 230 Volts? NO! The same people who will say the split phase Voltage is 115 V will also say the line Voltage, which is the amount that is split in half to get that 115 V is 220 V.Now, those are two totally inconsistent numbers. To be sensible we should say 110 V and 220 V or we should say 115 V and 230 V. But almost everyone, even the professional electricians who DO know better will tell your it is 115 V and 220 V. And there is no logical explanation for that.But back to tolerances and hourly variations in the actual Voltage delivered to a home. I do like to use 230 V so that is where I will start. Now, 10% of 230 is 23 so 230 V, +/-10% gives a range of 207 V to 253 V. Yes, that's a 46 Volt range. And 220 V and 240 V are both completely within it.And I will bet dollars to donuts that virtually every power company in every country on the planet will tell you that their hourly Voltage will vary by at least that 10%. None of them will be willing to guarantee any better percentage than that. Perhaps they may choose a slightly different base number, like 225 V or 235 V, but all of them are going to be in that general range.SO, as I said above, FOR ALL INTENTS AND PURPOSES; 220 V, 230 V, and 240 V and even 210 V and 250 V are all one and the same thing. The only differences are due to the time of the day and the load on the generators. They are all 230 V +/-10% regardless of what the countries, the power companies, or the clueless individuals who publish the numbers that are supposed to be what each country "is" say it is.As for practical operation of equipment, if you find that your area commonly has Voltage readings on the low side, then, by all means do set any power taps in it to 220 V or less. And if your power is commonly at a higher Voltage, do set them for 240 Volts. And if you find that you have a problem with one setting, then, by all means, try another.Just Go with the Flow (of the electrons/Voltages, of course).

author: srb1954
author_rank: Super Contributor
timestamp: November 19, 2023, 10:15:46 am
content: Quote from: Swake on November 18, 2023, 11:10:37 amI suggest you measure your actual mains voltage over a period of time and use the measured value as a guide to set the equipment input voltage to. It is rare that the mains is exactly at its nominal 230V and can be either higher or lower depending on your location relative to the supply transformer and other loads in your neighbourhood.At my house the nominal 230V mains is consistently above 235V so I use the 240V setting, where available on the equipment, for reduced power dissipation and a little extra margin against over-voltage transients.

author: Zero999
author_rank: Super Contributor
timestamp: November 19, 2023, 11:21:31 am
content: Much of Europe ran on 220V, whilst the UK ran on 240V. As mentioned above, the EU standardised on 230V, but set the tolerance range to cover both voltages, plus a fair margin.The original poster's location is Belgium, thus will most likely have a nominal voltage of 220V., but I would recommend setting it to 240V and set it to 220V, if it malfunctions or underperforms.

author: BeBuLamar
author_rank: Super Contributor
timestamp: November 23, 2023, 03:13:23 pm
content: In my house here in the US, the 240 is slightly more than 240V and the 120 is slightly more than 120V.

author: themadhippy
author_rank: Super Contributor
timestamp: November 23, 2023, 03:19:26 pm
content: QuoteApart from when your running lamps designed for 220/230v land on a 240v supply,the lamp life is noticeable reduced.

author: tooki
author_rank: Super Contributor
timestamp: November 23, 2023, 09:21:39 pm
content: Quote from: srb1954 on November 19, 2023, 10:15:46 amI was going to suggest the same thing. For example: at home, my mains tends to hover around 233V, but at work it’s often around 237V. So I’d choose 240V at work for sure, at home I’d decide depending on the device and whether it’s likely to misbehave with a bit too low voltage.

author: Brumby
author_rank: Unknown
timestamp: November 24, 2023, 12:17:59 am
content: When Australia changed to a 230V standard, they did it overnight, in a very clever way. . .Old: 240V +6%, -10%New: 230V +10%, -6%Do the math ... and you will smile.I suggest you select your voltage accordingly

author: tridac
author_rank: Regular Contributor
timestamp: November 24, 2023, 01:08:54 am
content: A lot of older HP test gear used linear regulators in the psu. The 5370 counter rear panel heat sinks can cause a burn when running from the uk 240v, which in reality. is often 245v or more. Even considered fitting an 20 volt or so bucking transformer to lose some of the volts to the lab. Other HP kit usually has a 240v setting and later kit with smps will be universal 115/230 and may even be more efficient at a higher voltage. An ali heat sink resistor bolted to the chassis can be good way to lose line volts in some cases.In general though, the psu seems to be the last bit of the design process, cheap and cheerful, poorly specced and rated parts, little or no ventilation, with the obvious result. Undervolting slightly is usually the best bet...