Electricity Supply

[srisatch]

Bought a new Acer Notebook

TOT, amazingly, given where I live, have produced Wireless Broadband

But

There is not sufficient electric power to charge the notebook. The old Dell charges, but not this one....Works fine in the UK and Europe.

Anyone got experience of this? What to do?

PS we notice the electric fluctuates wildly, often depending on time of day--pulsating Computer Screens-variable shower is it the house, the soi, the town, the country?

[The Dan Sai Kid]

Bought a new Acer Notebook

TOT, amazingly, given where I live, have produced Wireless Broadband

But

There is not sufficient electric power to charge the notebook. The old Dell charges, but not this one....Works fine in the UK and Europe.

Anyone got experience of this? What to do?

PS we notice the electric fluctuates wildly, often depending on time of day--pulsating Computer Screens-variable shower is it the house, the soi, the town, the country?

Why don't you speak to your electric company? Also, don't forget to use a surge adaptor!

Have you tried different plugholes to see if they work - sometimes in hotels the computer, or phone won't charge - so I check all plugholes and in the end I usually can find one!

[yeti]

You can try using a UPS (Uninterruptible Power Supply) which would filter flucutations of your power, giving you a constant output.

But if the electric company is not supplying enough power to your house, a UPS won't be enough to fix your problem.

[srisatch]

Thanks

Tried the Electric..according to them..no problem...though others in the soi say they have a problem!!

Tried a UPS..seems to make no diffrence...as you say..if not enough power in the first place!!

Shall have to buy a windmill.

In the morning there is power..but little water..in the evening no electric but plenty of water!

A month agoi there was a thunderstorm. Some lights in the house worked, others did not! Never seen variable power cut before!

[astral]

Most of the charger bricks are 100-240 volt so it should not matter if the local supply is poor.

Check the output of the brick with a meter.

Mine works even when we are on the generator, which is a low and erratic supply.

[Crossy]

Most of the charger bricks are 100-240 volt so it should not matter if the local supply is poor.

Check the output of the brick with a meter.

Mine works even when we are on the generator, which is a low and erratic supply.

That was my thought, it may be worth checking that your charger is 110-220V rather than 220V only (can't believe that it would be 220 only but you never know).

You need an on-line UPS (much more expensive) these can boost low voltage supply up to the correct level (and reduce overvoltages as well), could be a worthwhile investment if your power is as erratic as you suggest. APC make some very good ones, look on their website.

A cheaper option would be a voltage regulator (look in your local hardware store), these have motorised variac transformers, they don't react to rapid fluctuations but will take any input voltage 100-250V and push out a reasonably steady 220V.

Meanwhile get yourself a cheap meter and measure your voltage (carefully it can bite) anything under 210 or so needs investigating. Are you in the sticks on the end of a long supply line?

Edited March 9, 2006 by Crossy

[rishi]

Just to be sure - you have tried wether things work okay a different place, right? I once had the same kind of problems with a new laptop. It turned out to be the laptop itself, that had a problem with its internal affairs.

[tjo o tjim]

With a laptop, your problem is not likely the utility. Are you re-using a charger from your old laptop? Some of the Dells now require larger power supplies, so despite the cord fitting, it doesn't have enough juice.

I wouldn't recommend using a UPS if the voltage drops below 200V- you will just kill your (ups) battery with it. An Automatic Voltage Regulator is a better bet, since the laptop has its own battery.

One last thing- surge suppressors don't do any good unless your house wiring is grounded. (You need someplace to shunt the excess voltage to!)

[elkangorito]

With a laptop, your problem is not likely the utility. Are you re-using a charger from your old laptop? Some of the Dells now require larger power supplies, so despite the cord fitting, it doesn't have enough juice.

I wouldn't recommend using a UPS if the voltage drops below 200V- you will just kill your (ups) battery with it. An Automatic Voltage Regulator is a better bet, since the laptop has its own battery.

One last thing- surge suppressors don't do any good unless your house wiring is grounded. (You need someplace to shunt the excess voltage to!)

How interesting!

If you're smart, invert everything 'tjo o tjim' says to do or not to do. In other words, if he says do something, don't do it. If he says don't do something, do it.

Unless he can back up his "assumptions" with fact, his assumptions will remain as that...JUST ASSUMPTIONS.

There is little fact to be found in his statements. If you want FACT, ask qualified people. There are a few of us here.

[tjo o tjim]

elkangorito --

For my qualifications, I am a Professional Engineer, specializing in the design of electrical power systems for data centers.

While my professional experience is 85% in the US, I have lived in Thailand for over two years, and have had significant projects as well as minor "fixit" projects here.

There's my qualifications... What's yours?

[elkangorito]

elkangorito --

For my qualifications, I am a Professional Engineer, specializing in the design of electrical power systems for data centers.

While my professional experience is 85% in the US, I have lived in Thailand for over two years, and have had significant projects as well as minor "fixit" projects here.

There's my qualifications... What's yours?

I am an Electrical Engineer & have been employed as such since 1989. I am currently a Facilities Manager for a Data Centre (a 'critical' site) for one of Australia's banks. My forte is with power reticulation/control, switchboard design, motor control centres but not withstanding this, I've had ample experience with both static & dynamic UPS systems.

Here are your points that I question;

Your quote begins, my response is in red.

With a laptop, your problem is not likely the utility Upon what assumption do you base this?. Are you re-using a charger from your old laptop? Some of the Dells now require larger power supplies, so despite the cord fitting, it doesn't have enough juice. Good point.

I wouldn't recommend using a UPS if the voltage drops below 200V- you will just kill your (ups) battery with it. Obviously, this indicates a supply problem but wouldn't 'back-up' time be the answer to this situation? ie 1 hour battery back-up. An Automatic Voltage Regulator is a better bet, since the laptop has its own battery. Please explain 'Automatic Voltage Regulator'.

One last thing- surge suppressors don't do any good unless your house wiring is grounded. (You need someplace to shunt the excess voltage to!)

End of your quote.

Surge Suppression does require an adequate earth (which is few & far between in Thailand) & the 'retail' surge suppression is crap. Proper & adequate surge suppression can only be obtained by using MOV's (Metal Oxide Varistors) at the Main Distribution Board & are quite expensive. Surge Protection devices that can be purchased as an integral part of a 'power board' (for example) are often too slow to operate & as a result, quite often don't protect anything. It is therefore noteworthy to state what type of 'surge suppression' is required, if you suggest such a thing.

Excuse me for being brash but I did feel that you offered little explanation with your suggestions.

[tjo o tjim]

>With a laptop, your problem is not likely the utility Upon what assumption do you base this?.

Based on the idea that the lights work and the old laptop worked. Fundamentally no change in the electricity supply makes it more likely to be an equipment problem than a utility problem.

>I wouldn't recommend using a UPS if the voltage drops below 200V- you will just kill your (ups) battery with it. Obviously, this indicates a supply problem but wouldn't 'back-up' time be the answer to this situation? ie 1 hour battery back-up.

My experience in Thailand is that it only dips below the cut-in voltage of the inverter momentarily (if offline). This leads to the bypass contactor "chatter", and often causes the thermal overloads of the UPS unit to trip. The initial "Coup de fouet" characteristic of the battery discharge would tend to drop the battery voltage below a usuable level after a dozen or so cycles. This type of discharge pattern drastically reduces battery life, and can actually lead to fires. Since the poster has a laptop already, it has a built-in battery, and this is generally a more useful (and efficient) system.

>An Automatic Voltage Regulator is a better bet, since the laptop has its own battery. Please explain 'Automatic Voltage Regulator'.

These are common in Thailand, it's just a buck-boost transformer that automatically boosts the voltage if it drops below a certain threshold. Usually they have multiple taps, so they can help out in a range of -20% to +10% and get voltage +/-2.5% of nominal. If the problem is with utility voltage drop, this would do the job, without going to battery.

>Surge Suppression does require an adequate earth (which is few & far between in Thailand) & the 'retail' surge suppression is crap. Proper & adequate surge suppression can only be obtained by using MOV's (Metal Oxide Varistors) at the Main Distribution Board & are quite expensive. Surge Protection devices that can be purchased as an integral part of a 'power board' (for example) are often too slow to operate & as a result, quite often don't protect anything. It is therefore noteworthy to state what type of 'surge suppression' is required, if you suggest such a thing.

MOVs are often applied in commercial/retail equipment. My only reason for referring to it is that people everywhere think surge suppressors are the ultimate answer to electrical problems. Unfortunately, MOVs fail shorted, so they are also a fire hazard unless properly protected.

>Excuse me for being brash but I did feel that you offered little explanation with your suggestions.

Unfortunately, the down and dirty explanations often are too hard for people to understand. Simplifying things and giving people the core information that they need to solve the problem is easier than trying to explain the technical details. How many people just roll their eyes when you try to explain the difference between a common-mode and a normal-mode surge and the results on equipment and surge-suppression equipment? What about Coup de fouet?

[KhunMarco]

I always thought with a laptop you don't have to worry about power surges because of the AC adapter . Anyone of you pros care to confirm?

Thanks , much appreciated.

[elkangorito]

>With a laptop, your problem is not likely the utility Upon what assumption do you base this?.

Based on the idea that the lights work and the old laptop worked. Fundamentally no change in the electricity supply makes it more likely to be an equipment problem than a utility problem.

>I wouldn't recommend using a UPS if the voltage drops below 200V- you will just kill your (ups) battery with it. Obviously, this indicates a supply problem but wouldn't 'back-up' time be the answer to this situation? ie 1 hour battery back-up.

My experience in Thailand is that it only dips below the cut-in voltage of the inverter momentarily (if offline). This leads to the bypass contactor "chatter", and often causes the thermal overloads of the UPS unit to trip. The initial "Coup de fouet" characteristic of the battery discharge would tend to drop the battery voltage below a usuable level after a dozen or so cycles. This type of discharge pattern drastically reduces battery life, and can actually lead to fires. Since the poster has a laptop already, it has a built-in battery, and this is generally a more useful (and efficient) system.

>An Automatic Voltage Regulator is a better bet, since the laptop has its own battery. Please explain 'Automatic Voltage Regulator'.

These are common in Thailand, it's just a buck-boost transformer that automatically boosts the voltage if it drops below a certain threshold. Usually they have multiple taps, so they can help out in a range of -20% to +10% and get voltage +/-2.5% of nominal. If the problem is with utility voltage drop, this would do the job, without going to battery.

>Surge Suppression does require an adequate earth (which is few & far between in Thailand) & the 'retail' surge suppression is crap. Proper & adequate surge suppression can only be obtained by using MOV's (Metal Oxide Varistors) at the Main Distribution Board & are quite expensive. Surge Protection devices that can be purchased as an integral part of a 'power board' (for example) are often too slow to operate & as a result, quite often don't protect anything. It is therefore noteworthy to state what type of 'surge suppression' is required, if you suggest such a thing.

MOVs are often applied in commercial/retail equipment. My only reason for referring to it is that people everywhere think surge suppressors are the ultimate answer to electrical problems. Unfortunately, MOVs fail shorted, so they are also a fire hazard unless properly protected.

>Excuse me for being brash but I did feel that you offered little explanation with your suggestions.

Unfortunately, the down and dirty explanations often are too hard for people to understand. Simplifying things and giving people the core information that they need to solve the problem is easier than trying to explain the technical details. How many people just roll their eyes when you try to explain the difference between a common-mode and a normal-mode surge and the results on equipment and surge-suppression equipment? What about Coup de fouet?

In this post, it is apparent & real that the general populus DO NOT understand the fundamentals of electricity. Therefore, seeing 'lights' on a laptop or it's supply, generally mean nothing to them. It is therefore worthwhile mentioning that the input voltage to the laptop supply does comply with that of the manufacturer. ie if the external laptop power supply requires 110 volts, it should be obvious that that the required supply is as such. Consequently, advice needs to reflect this fact.

With regard to 'contactor chatter', most MODERN UPS units use IGBT (solid state) switching & consequently do not employ contactors. Are you confusing this with Power Factor Correction units?

Contactor chatter, as you say, is detrimental under these conditions but I do not believe that this is the case for current UPS units. Most UPS units now employ '12 pulse' transformers to help reduce the harmonics put back into the line. IGBT's do the switching & therefore create more harmonics. Contactors are not used in modern UPS units. It has been long known that contactors present a problem regarding 'fault current'. Under FAULT conditions, contactors generally react by 'pulsing', therefore creating a dangerous situation & generally increasing the 'let through' energy. In most UPS systems, the 'let through energy' (I squared T) is limited to 200 milli seconds, which the IGBT's control. After this time period, the UPS automatically changes to the 'by-pass' or 'battery' mode. The worst case is that the UPS switches off.

As for supply conditions, if the supply is poor enough to cause frequent transfer to 'battery' supply, it is therefore "common sense" to assess this occurrence & estimate 'battery back-up time' accordingly. Unless one is the Director of the electrical supply authority, one cannot change the quality of supply electricity.

MOV's DO NOT present a fire hazard, provided that they are the type installed to protect the entire distribution system. Generally, they debilitate by about 20% after each 'surge protection action'. Therefore, after 5 'surge hits', they need to be replaced. These devices are enclosed similar to that to BS88 HRC fuses.

Generally, the electrical supply cannot be relied upon in Thailand. As a consequence, one needs to assess the conditions & ensure that their equipment is appropriately protected. The purchase of a UPS is advised, although the type of UPS is to be questioned. A basic UPS will NOT filter the supply electricity. It will, however, detect anomolies in the electrical supply & switch to "battery" under these conditions. It is therefore wise to know for how long the electrical supply fails, so as one can decide upon the amount of "back-up" time needed by batteries. Batteries only go flat because the "back-up" time is not long enough...not because of "contactor chatter".

At the end of the day, ensure that you have the appropriate supply for your computer. If you need to protect your data, use a UPS with AN APPROPRIATE BACK-UP TIME. If you need to be really sure, employ a UPS that 'filters' the power as well as backs-up your system.

Edited March 23, 2006 by elkangorito

[tjo o tjim]

OK, this is getting well beyond the scope of Thai Visa, but, most consumer UPS models are offline, meaning that the inverter only operates when the mains voltage is inadequate. A fast-switching contactor is provided to isolate the inverter from the utility. Similarly, with an online UPS, a contactor is generally provided for backfeed protection of the static switch in consumer models.

The proper application of IGBTs in an UPS are in a Pulse-Width Modulated design, rather than a pulsed design. It is only possible to have a 12-pulse inverter on a polyphase UPS, which is not an option in residential applications, or in most small-scale UPS models. IGBTs can be used for both the rectifier and inverter, and solid designs can control power factor actively. The phase-shift trasnformers associated with 12 pulse (or 18-pulse) designs are generally not as good of a solution as an active (IGBT) front-end.

Contactors are not a good solution, but in single phase systems the typical solution is to series rate them with an internal fuse or circuit breaker to accommodate short circuit current.

MOVs are fine installed in distribution equipment because they are adequately protected. Ideally, there are multiple tiers of surge suppression at the incoming service, generators, sub-distribution panels and panelboards. Each level is coordinated with expected surge potential and further clamps the allowable spikes. Historically, MOVs applied in equipment where they can't easily be tested, checked, or replaced become fire hazards. You used to see this much more often than you do today, I will admit.

UPS units are not for long-term backup. Laptop batteries are intended for 2-4 hour run-time. Laptop batteries are more efficient than UPS batteries, since you aren't trying to do two extra AC/DC conversions. If you need extremely long battery run time, go with the laptop base-plate batteries, which give you up to 8 hours of run time. If you need more than an hour or two, the best solution is to have a generator and a diesel tank.

The decrease in life for batteries is a function of the number charge/discharge cycles; most UPS batteries are only good for 100 full discharges. My original point was that the voltage dips each time you start a discharge, and takes time to recover (fractions of a second). When you get multiple hits in a row, it is common to see the voltage drop below the cut-out voltage of the inverter, causing immediate shutdown. Depending on the amount of capacitance on the DC bus, this can happen in as few as 5-6 hits. Proper commercial UPSs force the load to stay on battery for at least a minute before transferring back to avoid this problem, but this can still cause a similar problem when repeated often enough.

[elkangorito]

OK, this is getting well beyond the scope of Thai Visa, but, most consumer UPS models are offline, meaning that the inverter only operates when the mains voltage is inadequate. A fast-switching contactor is provided to isolate the inverter from the utility. Similarly, with an online UPS, a contactor is generally provided for backfeed protection of the static switch in consumer models.

The proper application of IGBTs in an UPS are in a Pulse-Width Modulated design, rather than a pulsed design. It is only possible to have a 12-pulse inverter on a polyphase UPS, which is not an option in residential applications, or in most small-scale UPS models. IGBTs can be used for both the rectifier and inverter, and solid designs can control power factor actively. The phase-shift trasnformers associated with 12 pulse (or 18-pulse) designs are generally not as good of a solution as an active (IGBT) front-end.

Contactors are not a good solution, but in single phase systems the typical solution is to series rate them with an internal fuse or circuit breaker to accommodate short circuit current.

MOVs are fine installed in distribution equipment because they are adequately protected. Ideally, there are multiple tiers of surge suppression at the incoming service, generators, sub-distribution panels and panelboards. Each level is coordinated with expected surge potential and further clamps the allowable spikes. Historically, MOVs applied in equipment where they can't easily be tested, checked, or replaced become fire hazards. You used to see this much more often than you do today, I will admit.

UPS units are not for long-term backup. Laptop batteries are intended for 2-4 hour run-time. Laptop batteries are more efficient than UPS batteries, since you aren't trying to do two extra AC/DC conversions. If you need extremely long battery run time, go with the laptop base-plate batteries, which give you up to 8 hours of run time. If you need more than an hour or two, the best solution is to have a generator and a diesel tank.

The decrease in life for batteries is a function of the number charge/discharge cycles; most UPS batteries are only good for 100 full discharges. My original point was that the voltage dips each time you start a discharge, and takes time to recover (fractions of a second). When you get multiple hits in a row, it is common to see the voltage drop below the cut-out voltage of the inverter, causing immediate shutdown. Depending on the amount of capacitance on the DC bus, this can happen in as few as 5-6 hits. Proper commercial UPSs force the load to stay on battery for at least a minute before transferring back to avoid this problem, but this can still cause a similar problem when repeated often enough.

I fully agree with what you say. The only difference here is that the consumer is dealing with a Thai residential electrical supply. In this instance, I would whole heartedly suggest an Offline UPS with at least a 1 hour back-up capability. My thinking is that the supply is obviously faulty & therefore a Power Conditioner will not be able to handle this. The only solution under these circumstances, is to apply a UPS with a long back-up time. Obviously this will lead to considerable expense with regard to the shortened life of batteries but will provide the continuous supply required. Either pay for the supply to be improved or pay for batteries.

As for harmonics in commercial UPS systems, signal injection is the current best form of harmonic control. Not many UPS systems utilise harmonic control. Nonetheless, this need not be considered in a stand alone single phase residential system. I currently look after a building with about 3000 single phase Desktop computers operating (3rd harmonic possibilities). The UPS only needs to cater for a total of 600 kVA (not related to the number of Desktop units). The UPS units utilise 12 pulse txers with an unknown harmonic control element. I estimate the amount of wasted electrical energy at about 20% due to harmonics being present at the front end of the UPS (& throughout the system) & also harmonics being put back onto the system in general. Do you cater for harmonic control in your UPS design? Your advice on this matter would be appreciated.

Edited March 29, 2006 by elkangorito

[Totster]

OK, this is getting well beyond the scope of Thai Visa, but, most consumer UPS models are offline, meaning that the inverter only operates when the mains voltage is inadequate. A fast-switching contactor is provided to isolate the inverter from the utility. Similarly, with an online UPS, a contactor is generally provided for backfeed protection of the static switch in consumer models.

The proper application of IGBTs in an UPS are in a Pulse-Width Modulated design, rather than a pulsed design. It is only possible to have a 12-pulse inverter on a polyphase UPS, which is not an option in residential applications, or in most small-scale UPS models. IGBTs can be used for both the rectifier and inverter, and solid designs can control power factor actively. The phase-shift trasnformers associated with 12 pulse (or 18-pulse) designs are generally not as good of a solution as an active (IGBT) front-end.

Contactors are not a good solution, but in single phase systems the typical solution is to series rate them with an internal fuse or circuit breaker to accommodate short circuit current.

MOVs are fine installed in distribution equipment because they are adequately protected. Ideally, there are multiple tiers of surge suppression at the incoming service, generators, sub-distribution panels and panelboards. Each level is coordinated with expected surge potential and further clamps the allowable spikes. Historically, MOVs applied in equipment where they can't easily be tested, checked, or replaced become fire hazards. You used to see this much more often than you do today, I will admit.

UPS units are not for long-term backup. Laptop batteries are intended for 2-4 hour run-time. Laptop batteries are more efficient than UPS batteries, since you aren't trying to do two extra AC/DC conversions. If you need extremely long battery run time, go with the laptop base-plate batteries, which give you up to 8 hours of run time. If you need more than an hour or two, the best solution is to have a generator and a diesel tank.

The decrease in life for batteries is a function of the number charge/discharge cycles; most UPS batteries are only good for 100 full discharges. My original point was that the voltage dips each time you start a discharge, and takes time to recover (fractions of a second). When you get multiple hits in a row, it is common to see the voltage drop below the cut-out voltage of the inverter, causing immediate shutdown. Depending on the amount of capacitance on the DC bus, this can happen in as few as 5-6 hits. Proper commercial UPSs force the load to stay on battery for at least a minute before transferring back to avoid this problem, but this can still cause a similar problem when repeated often enough.

I fully agree with what you say. The only difference here is that the consumer is dealing with a Thai residential electrical supply. In this instance, I would whole heartedly suggest an Offline UPS with at least a 1 hour back-up capability. My thinking is that the supply is obviously faulty & therefore a Power Conditioner will not be able to handle this. The only solution under these circumstances, is to apply a UPS with a long back-up time. Obviously this will lead to considerable expense with regard to the shortened life of batteries but will provide the continuous supply required. Either pay for the supply to be improved or pay for batteries.

As for harmonics in commercial UPS systems, signal injection is the current best form of harmonic control. Not many UPS systems utilise harmonic control. Nonetheless, this need not be considered in a stand alone single phase residential system. I currently look after a building with about 3000 single phase Desktop computers operating (3rd harmonic possibilities). The UPS only needs to cater for a total of 600 kVA (not related to the number of Desktop units). The UPS units utilise 12 pulse txers with an unknown harmonic control element. I estimate the amount of wasted electrical energy at about 20% due to harmonics being present at the front end of the UPS (& throughout the system) & also harmonics being put back onto the system in general. Do you cater for harmonic control in your UPS design? Your advice on this matter would be appreciated.

My word... you two have certainly got hardons for UPSs...

totster

[kdvsn]

Aside from the fact that the company trying to sell this particualar unit is trying to charge a ridiculous price for it, what do you think about the technical merits of using a device like this one to protect expensive electronic equipment (particularly stereo equipment) in Thailand http://www.psaudio.com/products/p300.asp ?

To my limited understanding, it digitally regenerates the AC signal into a clean sine wave having a selectable frequency and voltage. I've noticed that units like these often show up on the used market in the States for a fraction of their retail price, maybe because while they sound like a good idea, in areas that have a relatively good power company it may be hard to demonstrate a tanglible advantage of this device. Just curious whether experts in the field consider the concept behind this sales this device to be legitimate.

[elkangorito]

Aside from the fact that the company trying to sell this particualar unit is trying to charge a ridiculous price for it, what do you think about the technical merits of using a device like this one to protect expensive electronic equipment (particularly stereo equipment) in Thailand http://www.psaudio.com/products/p300.asp ?

To my limited understanding, it digitally regenerates the AC signal into a clean sine wave having a selectable frequency and voltage. I've noticed that units like these often show up on the used market in the States for a fraction of their retail price, maybe because while they sound like a good idea, in areas that have a relatively good power company it may be hard to demonstrate a tanglible advantage of this device. Just curious whether experts in the field consider the concept behind this sales this device to be legitimate.

With regard to protecting equipment, the importance that you place on the equipment is your decision. For example, the most important thing to protect with computers is the DATA that is stored within them. If you have spent 6 months developing a publication that is worth substantial dollars to you, then it makes sense to employ an appropriate UPS system, else an electrical supply variation or failure may result in the loss of such valued data.

Again, this is your decision. Is your equipment/data worth spending substantial money on protection? What is the condition of the electrical supply? If it is poor & you still require "substantial protection", you will pay dearly for appropriate supply protection. This will be primarily due to the amount of batteries needed & the maintenance thereof. In Thailand, where the ambient temperatures are generally above 30 degrees Celsius, battery life is greatly reduced...particularly if the batteries are of the "Gel" type. (Lead Acid batteries are best).

At the end of the day, YOU must decide how valuable your equipment/data is & make a decision based upon your evaluation.

[tjo o tjim]

Sorry, Totster... but it pays the bills!

[MarkBKK]

This is truly a wonderful thread. Great fun.

A bit trollish, but aren't backups to protect data?

[tjo o tjim]

This is truly a wonderful thread. Great fun.

A bit trollish, but aren't backups to protect data?

The problem in Thailand is that you need backup equipment as well for continuity of operations. Even simple stuff... you never know how long something will take to replace if it breaks. A "little" retail operation near me needs duplicate equipment for everything to make sure a power surge doesn't kill them for a week or month.

Even in your personal life, is there information you can't live without for a day? An hour? Oddly, things have changed a lot in that respect over the last 5 years.

For what it's worth...

[gharknes]

My simple donation to your post

you say no power ? what exactly do you mean, is your house getting the full 220volts or is it less ? get a simple multimeter to check this

Even if your power is down a little it will not prevent your laptop power supply from working and charging your battery, I think you may have a simple problem with your laptop power supply, these work by reducing the voltage from the mains to uner 30volts, this is regulated and even if your mains voltage dropped slightly it won't make a difference

You say the soi power is low, again what does this mean, do your lights dim when the aircon comes on or fridge etc, this is quite normal and is caused by a higher current demand on your supply cable which then sees a slight drop in voltage due to the resistance of the cable, again shouldn't cause any problems.

I think you simply have a faulty power supply for your laptop.

[sungod]

Go on, someone ask me one on sport!

[elkangorito]

The problems with the supply of electricity to establishments are not few. Such problems can be;

i) a total loss of supply (black out).

ii) a "short time" loss of supply, usually limited to more than 10 milli seconds to maybe 100 milli seconds (a brown out...dimming of lights etc).

iii) voltage spikes, which can be many times greater than the normal Peak voltage. Spikes can lead to the destruction of equipment.

iv) degradation of the sinusoidal waveform. This can be caused by harmonics generated by industry using many electronics devices (or even some UPS units).

v) change of phase rotation or phase reversal. Usually only affects poly-phase systems.

vi) a broken neutral conductor, which can cause abnormally high voltages within a supply network or establishment.

vii) a resistive earth connection or a broken main earth conductor, which can allow a varying (floating) voltage on the neutral conductor. Such a situation is common in Thailand (because earthing is not common) & causes many strange problems with sensitive &/or electronic equipment. Usually leads to shortening the life of such equipment.

viii) "long time" low supply voltage due to incorrectly sizing or upgrading the local network supply cables as area "maximum demand" increases.

ix) a decrease in Power Factor, resulting in more current being used. If the supply cables are too small, voltage drop becomes a problem as well as overheating of the cables involved. Could result in fires.

UPS units can provide protection for all of these events, depending upon the type of UPS one purchases. Not withstanding this, having an MEN link & an appropriate earthing system in your home can help to limit these problems for the residential consumer.

See the "Breaker Box Wiring" post for more details about this.

Edited April 1, 2006 by elkangorito