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equipment damage due to voltage supply

equipment damage due to voltage supply

equipment damage due to voltage supply

(OP)
hello guys,

i need some help here.

1. This evening after back from class, i have found that some of my electrical devices were damage (fan, hand-phone charges) but my laptop still working. In the beginning i thought it happens because of over current (lightning). However, the fuse (13A) is still in good condition. Both equipment are off while i'm out. Some of my friend claimed that their laptop were damage due to this unknown problem but not everyone were affected even in same room.

2. Plus, earlier this morning, i found that my ceiling fan was too slow ( not in normal speed) which i think not enough voltage supply. But now the speed is back to normal right after we found out about the unknown problems.

3. finally,late evening, the whole floor were trip and all of the problems only happen to my floor only. Other floor is not affected by those problems.

So, can someone help me to with this because im afraid it will happen again. The losses are too big because it involved laptops and other expensive equipment.

Thanks for your concerns :)

RE: equipment damage due to voltage supply

Transient voltages don't blow the fuse typically, because of their short duration.

Get a surge suppressor on your sensitive equipment.

Best to you,

Goober Dave

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RE: equipment damage due to voltage supply

Such things can happen if the neutral of the 3-phase, 4-wire supply is disconnected. It could be in the distribution board for the specific floor or individual house. If it is only one room affected in a house, then it could even be the switchboard in that floor.
Needs patient investigation.

RE: equipment damage due to voltage supply

We (our house) lost the neutral wires underneath the meter connection after the meter was swapped for the new "intelligent "NSA-EPA-FERC-monitored-power" meters 8<) .

Yes, the PC is likely to be good - ours were because they on a UPS that provided a secondary protection against the surge. EVERY OTHER electrical and elecgronic device running was lost: clocks, fan motors, AC, microwave, etc. Pure resistance appliances (stove, light bulbs) survived.

Our whole house surge suppressor also blew out - literally ! - with a large hole in the side of the box and melted connections inside.

RE: equipment damage due to voltage supply

You have good clues here; need to get the facts straight to follow through to proper conclusion....

You said were damage (fan, hand-phone charges) but my laptop still working. ... Both equipment are off while i'm out.

Both what? Fan & charger broke? But later you say the fan was ok... So what was off? The broken stuff or the stuff that survived? Kinda important...

If something is 'turned off' and that means it is physically disconnected BY A DISTANCE BETWEEN CONDUCTORS LIKE IN A SWITCH, and it fails, that is NOT from lost neutral, but from a voltage high enough to ionize the airgap and jump across: aka, lightning.

If something is 'turned off' like a printer, most TVs today, etc, that do not have a physical disconnect switch but just 'turn off' in logic circuit, then loss of neutral can still take them out.

UPS's are cheap enough today; in addition to the great idea of putting your stuff on surge protector extension strips, I would buy a $ 20 UPS and run all the stuff thru it - even more protection than just the MOVs in the surge strips.

Personally I would be more concerned about staying alive at this point - the descriptions in general you give say HEAT and possible FIRE to me. I would be all over building maintenance to get this fixed before I wanted to sleep there another night!

www.KilroyWasHere<dot>com

RE: equipment damage due to voltage supply

Always use a surge protector strip for electronics. Sounds like either a power surge or brown out condition which would be like repeatedly unplugging and plugging in a device several times a second causing loss of steady 60 cycle power. Don't think there is any kind of protector for home use that can deal with a brown out condition and why I turn off anything in the home with circuitry inside during high winds or T-storms.

Seems strange that you say things were turned off. Guessing a lot of electronics these days are still using processers and such even when turned off but really when you think about it modern devices do not ever turn off completely they go into "standby mode". This is why things like TV sets turn on with the remote. Even when turned off a processer is always running and searching for the remote signal to tell it turn on. Now that I think about it I may start unplugging electronics around the house during storms instead of just turning them off.

RE: equipment damage due to voltage supply

(OP)
thank you very much for all the response and answer. now im very clear about the problems.

1. my fan (40W)are damage but not the fuse (13Amp) (supply voltage:240V). maybe because the fuse are too big. i should use 3amp fuse. am i right?
Same problem goes with the charger.

however DRWeig said :
Transient voltages don't blow the fuse typically, because of their short duration.

Does it means fuse doesn't work with transient voltage? because from what i know, any current above the maximum rating will blow the fuse even it is in short duration. Plus, high current - small melting time . so how can high current pass fuse without blow it?


2. my laptop is safe from the surge because the laptop's power supply comes with transient voltage suppressor or any surge protector.

please correct me if im wrong. thank you again.

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