Re: Panasonic TC-P50X3 Totally DEAD
If it was incoming via a TV cable, then what was an outgoing path? If both do not exist, then no electricity and no damage.
Most common source of surge damage is, for example, a lightning strike to AC wires far down the street. That surge was incoming to every appliance. But not all appliances provide a best path to earth. Your TV cable (should) already has superior protection. But that same earth ground means a TV cable was a best outgoing path to earth. Incoming on AC mains to everything. Outgoing to earth via a TV cable. Damage...
westom
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Last Activity: 10-19-2013, 09:37 AM
Joined: 07-25-2010
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Last edited by westom; 10-19-2013, 09:37 AM. -
Re: High Voltage Shocker - components blown in new machine
If it is a varistor, then remove the defective part and power it up. The varistor, in normal operation, acts like it is not there.
Do this because the same part could also be an inrush current limiter. If the later, then it will not power up.
Before optaining the proper part, first determine what the input voltage should be on its label (often near the power cord). If it is an 85 to 265 volt power supply (as it may be from what little I can gather from the pictures), then a 150 volt varistor...Leave a comment:
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Re: High Voltage Shocker - components blown in new machine
Most likely. That is why the fuse would blow. However, to say something that is useful means you must first provide some hard facts. Such as voltage numbers found on some label nearby the power cord attachement.
Pictures show what could be a supply that works from 85 to 265 volts. Then damage (due to UK voltage) should not happen. Pictures do not show enough numbers from enough parts. If that box is not for 230 volts (85 to 265), then a 400 volt capacitor or diodes (not shown) could be damage....Leave a comment:
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Re: Vizio E371VA lightning surge - no pic or sound
Well, you did not give numbers to three digits. The 24 volt numbers need not be so accurate. But the 12 volt number had to be. Also other voltages much exist and were not reported. So no. Nobody can say with certainty. Each answer is only as useful as the facts (especially numbers) it is based upon....Leave a comment:
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Re: Vizio E371VA lightning surge - no pic or sound
Descxribed was how a mainboard often is damaged. Identify the incoming and outgoing path. If your cable was properly earthed BEFORE entering, then that was not an incoming path.
A most common path is a current incoming on AC mains. Best 'outgoing' path to earth would be an HDMI port. Current is everywhere, simultaneously, in that path - incoming and outgoing. But often the outgoing path (HDMI) is only damaged.
Its your gamble to replace the mainboard. Since everything you can do to identify...Leave a comment:
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Re: Vizio E371VA lightning surge - no pic or sound
It's called electricity. If an incoming path exists but no outgoing path, then no electricity exists. Your answer starts by identifying both the incoming and outgoing path. Then something (not everything) in that path may be damaged.
A multimeter can measure DC voltages to three digits. BTW, a numbers that is near 12 volts can be completely defective. The number is more important than declaring "good or bad".
Measuring is a good place to start. Since nothing will make sense if a power...Leave a comment:
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Re: Sliced Me Varistor, Captain!
Assuming those are caps - then they are part of circuitry that makes dirtiest power from a UPS irrelevant. Some the dirtiest power seen by a supply comes from a UPS in battery backup mode. Filtering also exists for other anomalies including those defined by FCC regulations.
Leakage numbers of 10 or 30 milliamps is about 1000 times too large. That filter must leak only microamps. Capacitance is chosen as a compromise between safety issues and noise filtering.
A varistor is part of circuitry that does better protection...Leave a comment:
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Re: Think my fridge might be causing small power spikes?
Which confirms what was posted previously....Leave a comment:
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Re: Think my fridge might be causing small power spikes?
An honest answer must first identify the defect. Nobody can say what is defective without specific numbers. To have the defect identified and problem solved in the next post means buying or borrowing a multimeter. Typically $5 or $18 in any layman's store including Harbor Freight, Wal-Mart, and K-Mart. More expensive ones in Radio Shack, Home Depot, Lowes and Sears.
One minute of labor; taking numbers from six wires (and not disconnecting anything) means a definitive answer. To both identify a defect and to...Leave a comment:
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Re: Think my fridge might be causing small power spikes?
Points 1 through 4 only dispell irrelevant myths. Point five is the OP's topics. Why are you introducing other irrelevant semiconductors? Why are you ignoring what is significant including a possible code violation? Please address the OP's noise problem. A spike that is probably no more than tens of volts. And that maybe bypassing supply circuits that make noise (and larger spikes) irrelevant.
Your reply should be discussing point 5 that said, "Fifth, topic is about noise from a mini-fridge."...Leave a comment:
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Re: Think my fridge might be causing small power spikes?
First, all those components provided protection.
Second, today 120 volts is significantly filtered; seriously reducing or eliminating spikes. Then converted to a higher voltage (over 300 volt) radio frequency spikes. Even noisy AC is converted to a higher and 'dirtier' voltage. Then superior filters, galvanic isolation, etc convert that intentionally made 'dirtiest' power into rock solid and cleanest low voltage DC. Why? Best protection and superior filters, already inside electronics, must clean 'intentionally...Leave a comment:
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Re: Think my fridge might be causing small power spikes?
Every appliance has surge protection. How often do you replace dimmer switches because an air conditioner switched off? Never? Long before PCs existed, 120 volt electronics were designed to withstand up to 600 volt spikes without damage. Today's electronics are even more robust.
This 120 volt UPS outputs 200 volt square waves with a spike of up to 270 volts when in battery backup mode. Why is that ideal power for computers. All electronics already contain protection that even makes 'dirty' UPS power irrelevant....Leave a comment:
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Re: Think my fridge might be causing small power spikes?
Two wire receptacles are not so much a problem. More problematic are three prong receptacles where some safety ground wires are missing or compromised.
As budm's video notes, to create 1000 volt spikes means a capacitor that is also at 1000 volts. A 1000 volt capacitor installed to make a spike? 1000 volts inside that refrigerator would probably destroy any internal capacitor and even wire insulation. Assuming a capacitor even exists. Even sparking across a switch would cause its switch to destroy itself....Leave a comment:
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Re: Think my fridge might be causing small power spikes?
First, when trying to buy a 'high quality' protector, first read its spec numbers. Folr example, its let-through voltage may be 330 volts. How often does your 120 volt refrigerator create spikes exceeding 330 volts? Never unless it is also destroying itself.
Second, protectors are not designed for frequent surges. They are designed for rare transients that might occur once every seven years. If your refrigerator is created so many spikes so often, then you may have to replace that tiny (and $80) protector...Leave a comment:
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Re: UPS external battery mod.
That last option is most likely. I have put a scope on a similar UPS. That 120 volt output was 200 volt square waves with a spike of up to 270 volts. Ideal perfect power for all electronics. And harmful to some motorized appliances and power strip protectors. If your meter is not RMS type, then it is trying to measure the best it can.
Now, what is battery voltage when powering that 40 watt light bulb? If above 11.7 volts DC, then the UPS is outputing its best voltage and waveform. Measure the battery. If nearly at or above 12, then...Leave a comment:
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Re: Overloaded PSU: what effect does it have
Undefined is even what fails. No numbers are provided. Does a program crash? Does the computer lock up? Does it simply power off? What do system (event) logs report? What do the manufacturer's comprehensive diagnostics report? What exactly is every error message? Your help is only as useful as facts that you first provide. Currently very few hard facts were posted.
Never fix something by just replacing parts. Also called shotgunning. First identify a fault using information such as requested above. Once the defective...Leave a comment:
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Re: Sony KDL-46S504 - Replaced Power Supply, No Picture
Appreciate how a surge does damage. A surge does not enter on AC mains, destroy a power supply, and stop. A surge must first have the same current flowing everywhere, simultaneously, in a path from the surge source (ie cloud) to earth. If current entered on AC mains, then some other path must be the outgoing to earth.
A typical path is outgoing via the cable TV coax. Because all cable TV wires are required to be earthed before entering the building. Therefore the front end (signal) circuits could be damaged....Leave a comment:
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Re: Overloaded PSU: what effect does it have
True if assumptions are not based in how a computer works. A power controller must 'approve' all inputs before it permits a CPU to even execute the first machine code instruction (BIOS). Your 'swap' implies a power controller did not get a good signal from the original supply. Got a good signal from the new supply. Then let the CPU execute.
From information provided, nobody can say if that supply was undersized or (what happens more often) suffered from a manufacturing defect. The list of failures that means visual...Last edited by westom; 05-09-2011, 02:51 PM.Leave a comment:
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Re: Overloaded PSU: what effect does it have
Numerous questions and some misinformation are posted. First, 350 watts provided by some better manufacturers are also called 500 watts by other supply manufacturers. Neither is lying. Both are measuring different numbers. Many computer assemblers would not know the difference.
Second, irrelevant is watts. Your concern is current for each DC voltage. Nobody can define a power supply as undersized without numbers. Obtain those numbers by buying or borrowing a multimeter. A tool so idiotly simple as to be sold even...Leave a comment:
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Re: Homemade surge protector
That was how surge protectors worked even 100 years ago. Today we do same with Gas Discharge Tubes (GDTs). But MOVs are some of the best components for a least amount of money.
Critical is how each MOV connects an incoming wire to earth. Noted was the term 'low impedance'. Sharp wire bends or wires inside metallic conduit increase that impedance unacceptably. Wire distance (not wire thickness) is more important. The MOVs (or spark gap) will only be as effective as the impedance (not resistance) of that connection to single point earth...Leave a comment:
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