Computer and Voltage issues help

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kyleincambo
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Re: Computer and Voltage issues help

Post by kyleincambo »

juansweetpotato wrote: Sat Jun 24, 2017 6:00 pm
kyleincambo wrote: Sat Jun 24, 2017 10:28 am

I got a UPS that has a green light and a yellow light and red light. Green is always on. If the yellow light blinks its being used, if it stay lit it has no issues. It clicks everytime before the yellow light blinks meaning some kind of voltage issue which happens a whole lot. Our house is decently far from the main street. Im American so I dont do well with meters but I would say two and a half full size soccer fields. Lets put it this way. The internet guys were not happy about how far they had to run the fiber optic line.

So what are you getting at? Does that make a difference?
Like I said in an above post, I did a job in SNVL with a business that was slightly further than your house appears to be from the post. It was measuring 160v most of the time. You can buy a ring meter for about $20 in the electrical shop at the top end of the Samudera Rd. Just opposite the market if you should want to. It sounds like it may be better to move eventually. But maybe best to check first.
Other jobs I did there I was getting a reading of about 180v lowest.

Im from the States where the voltage output is 120v across the board. Why should it matter if my house is getting lower voltage than the 220v most get.
Shouldn't it not really matter? Im just trying to understand what your saying. We just signed a lease for a year, and we love the house and area, so moving is not in our plans. A little more info, and context would be greatly appreciated juan.
AlonzoPartriz
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Re: Computer and Voltage issues help

Post by AlonzoPartriz »

kyleincambo wrote: Sat Jul 01, 2017 10:15 am
juansweetpotato wrote: Sat Jun 24, 2017 6:00 pm
kyleincambo wrote: Sat Jun 24, 2017 10:28 am

I got a UPS that has a green light and a yellow light and red light. Green is always on. If the yellow light blinks its being used, if it stay lit it has no issues. It clicks everytime before the yellow light blinks meaning some kind of voltage issue which happens a whole lot. Our house is decently far from the main street. Im American so I dont do well with meters but I would say two and a half full size soccer fields. Lets put it this way. The internet guys were not happy about how far they had to run the fiber optic line.

So what are you getting at? Does that make a difference?
Like I said in an above post, I did a job in SNVL with a business that was slightly further than your house appears to be from the post. It was measuring 160v most of the time. You can buy a ring meter for about $20 in the electrical shop at the top end of the Samudera Rd. Just opposite the market if you should want to. It sounds like it may be better to move eventually. But maybe best to check first.
Other jobs I did there I was getting a reading of about 180v lowest.

Im from the States where the voltage output is 120v across the board. Why should it matter if my house is getting lower voltage than the 220v most get.
Shouldn't it not really matter? Im just trying to understand what your saying. We just signed a lease for a year, and we love the house and area, so moving is not in our plans. A little more info, and context would be greatly appreciated juan.
I've changed user ID.

Your power supply will probably auto switch between 120v and 220v. If it doesn't auto switch, it will have a manual switch on the back.

But as in the article I posted below on PSUs and brownouts, both standard operating voltages have + and - tolerances.

If a device that is made to operate between 180 and 265v, goes above or below these tolerances then problems can occur.

The computer will switch itself off if the supply voltage drops below 180v. If the components are cheap it may well carry on working, but will cause failures at some point along the line. The low voltage effects different components in different ways.

I would buy a ring meter and check the voltage as it comes into your house. I very much suspect your getting below 180v.

If your determined to stay.

Check the voltage at the electric post outside and if it's 190v or above, measure the cable diameter to see if it's big enough.

There are tables that will show you voltage drop on different sized cables online.

Check if it is the right size, if it isn't you can get an electrician to replace it. You don't need EDC to do it. This will only work if there is a big voltage difference between the post and your house.

This I posted earlier which probably identifies the problem you had before you bought the UPS of the computer switching itself off.

A brownout is an undervoltage condition, when the AC supply drops below the nominal value by about 10% (Nominal meaning 110-120 or 220-240 in most places). So in the US a brownout might be defined as the AC voltage dropping below 99V. The Intel specification for ATX power supplies specifies that voltages between 90 and 135, and 180 and 265 should allow correct power supply operation (section 3.1), so the power supply will still run normally even when a noticeable brownout occurs.

Some people also include very brief power dropouts (under 30mS, or about 2 AC cycles) as brownouts, as incandescent bulbs will briefly, but visibly, dim during that time similar to a real undervoltage condition.

In either case, Intel defines them as undervoltage conditions, and discusses what requirements an ATX power supply has to follow under such conditions in section 3.1.3 of Intel's ATX12V Power Supply Design Guide

The power supply shall contain protection circuitry such that the application of an input voltage below the minimum specified in Section 3.1, Table 1, shall not cause damage to the power supply.
Typically power supplies have an input section composed of a bunch of interesting circuitry that, at the end of the day, provides about 308 VAC to a transformer, which then powers the regulation and conditioning circuitry. This circuitry actually forms the major basis of the regulation circuitry, and if you are using less than the full wattage of the power supply may be able to manage with significant undervoltage conditions without falling out of regulation on the output side.

When a brownout occurs, the powersupply will attempt to deliver the rated current for as long as it can (based on the incoming voltage and current) and if it cannot maintain regulation it'll deassert the Power Good signal going to the motherboard. The motherboard is responsible for deasserting the power on signal going to the supply, and if it does so in time, then the supply will drop all its output and turn off.

If the motherboard fails to do this, the powersupply should drop its rails when it falls too far out of regulation, but that is not guaranteed, and with low quality power supplies you may find your components and motherboard receiving undervoltage conditions as well.

What happens at that point depends on how robust those components are, but it's generally not a good thing as the components attempt to operate at the lower voltage. Keep in mind that the power supply always supplies an undervoltage on power down for a brief time (dropping the outputs to 0 is not instantaneous) so very brief undervoltage periods are fine. The problem only occurs if the power supply remains in an undervoltage state for a long period of time, which can only occur if both the power supply and motherboard fail to realize the problem, and continue to attempt to operate.

Keep in mind that the Intel specification is not much more than an industry guideline, and there are no certifying bodies. Even good power supplies are not bound by any agreement to follow its recommendations. My favorite section is 3.1.5. I've seen many power supplies, both expensive and cheap, fail to keep those recommendations!

The specific effects differ depending on the component being discussed, which is really a separate discussion.

https://superuser.com/questions/113113/ ... so-harmful
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AndyKK
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Re: Computer and Voltage issues help

Post by AndyKK »

Lots of stuff interesting in this thread, but well over my head. I brought my laptop with me from the UK. Toshiba, the power here in Koh Kong is up and down, the worst I have come across in Cambodia. The transformer blow on the power lead. I went to the local computer shop for the repair. They did not have Toshiba but replaced it with the appropriate AC adapter, but having to re-attach the wire which plugs into the laptop. The shop owner told me never to leave it plugged in the mains for long periods.
Always "hope" but never "expect".
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