How dangerous is a PSU that lacks an MOV in the transient filtering stage

[strollin]

If you are worried about supply line fluctuations, you might consider a UPS (Uninterrupted Power Supply).

A surge protector is basically a fuse, more or less, that is sacrificial. Should a large transient spike come through (such as a lightning strike) then the MOV or MOVs direct the excess current to ground. In case of a direct lightning strike, the surge protector may sacrifice itself in order to protect what's plugged into it.

It also depends on how good the electric supply is where you live. For instance, where I live, lightning is pretty rare and so little is done to prepare for a lightning strike. We don't seem to have large fluctuations in our electric supply that cause problems for electronic equipment. As a result, I don't plug things into a surge protector and have never had any failures because of it. YMMV.

Having an MOV in the PSU itself is simply extra protection. It would be able to handle a certain amount of transient voltage spikes but an external surge protector offers better protection.

 

[soarwitheagles]

If you are worried about supply line fluctuations, you might consider a UPS (Uninterrupted Power Supply).

A surge protector is basically a fuse, more or less, that is sacrificial. Should a large transient spike come through (such as a lightning strike) then the MOV or MOVs direct the excess current to ground. In case of a direct lightning strike, the surge protector may sacrifice itself in order to protect what's plugged into it.

It also depends on how good the electric supply is where you live. For instance, where I live, lightning is pretty rare and so little is done to prepare for a lightning strike. We don't seem to have large fluctuations in our electric supply that cause problems for electronic equipment. As a result, I don't plug things into a surge protector and have never had any failures because of it. YMMV.

Having an MOV in the PSU itself is simply extra protection. It would be able to handle a certain amount of transient voltage spikes but an external surge protector offers better protection.

Strolling,

Ok, thank you for bringing even more clarity. I am trying to be as safe as possible because my new build is a bit expensive now.

I too live in N. Cal and where I live the lightening strikes are also fairly rare and large fluctuations in our electric supply that cause problems for electronic equipment are also rare. So, I suppose I do not have much to worry about.

I am not sure what PPMcQuire is referring to when he speaks about "brown outs."

Is he referring to when the electrical grid is overwhelmed [like during Gov. Gray's time], when they would lower the voltage or something like that?

Soar

 

[soarwitheagles]

Eh, no not at all.

I'm saying if your house gets struck by lightning using a surge protector takes your chances from pure luck to about 50/50 that all your junk might be fried. As in, there is a 50/50 chance that it wont trip or wont be enough to kill the travel of electricity.
Keep in mind, surge protectors don't do anything against power browns. The quality of PSU determines how many browns it can handle while still feeding your electronics smooth power.

Thanks again for the clarity on the surge protector and lightening strikes.

Ok, what are power browns?

Soar

 

[PP Mguire]

A power brown is when the power dips below normal voltage. If something happens to the grid or whatever might happen, it is known that the power levels can drop causing a brown. Basically what happens is the power going to your house is significantly less and cause damage to any of your electrical items. When this happens you can see the lights physically dim down for a period of time, fans go slower, ect. Most of the time with a quality PSU if a brown happens your computer instantly shuts off due to lack of proper AC voltage coming off the wall. Cheaper PSUs don't do this and continue to run causing a serious ripple in power going to your components which normally causes them to die or fry.

 

[soarwitheagles]

A power brown is when the power dips below normal voltage. If something happens to the grid or whatever might happen, it is known that the power levels can drop causing a brown. Basically what happens is the power going to your house is significantly less and cause damage to any of your electrical items. When this happens you can see the lights physically dim down for a period of time, fans go slower, ect. Most of the time with a quality PSU if a brown happens your computer instantly shuts off due to lack of proper AC voltage coming off the wall. Cheaper PSUs don't do this and continue to run causing a serious ripple in power going to your components which normally causes them to die or fry.

Wow! Dude, you really know how to open eyes!

Ok, I wasn't sure what brown outs were...but I remember some years ago [2000-2001] in California, we experienced this exact phenomenon that you so clearly describe. California had a shortage of electricity caused by market manipulations and illegal shutdowns of pipelines by Texas energy consortiums and the result were these rolling brown outs you so clearly describe.

I never realized the damage to components that could do.

Fortunately, we have been free from that insanity now for over 10 years, but I will keep it in mind just in case the politicians mess things up here again.

BTW, the brown outs were the main reason Governor Gray was removed from office!

Soar

 

[PP Mguire]

I think you are speaking of black outs where the power gets completely shut off. Last time we had that here was winter of 2011 during the stupid ****ing Super Bowl. It was below 20f here and all the rural areas had blackouts that lasted over 10 hours a piece. It was snowing, icing, and many many many people had no power, heat, or hot water. Friend of mine had a new born at the time too. SO many people were ****ed and there was a huge protest and everything.

A brown out is when the voltage has a severe drop in power, not completely off. Brown outs can come from a drop in the grid from somebody ramming their car into a pole, something happening to a main line, or even severe weather catching crap lines making your power dim out.

On the subject though, black outs and power loss can also damage your electronics. When the power comes back on it is technically a surge because it is a huge rush all at once. Whenever the power goes out from a storm or black out make sure to turn off your surge protector until the power comes back on.

 

[jasonalwaysready]

California had a shortage of electricity caused by market manipulations and illegal shutdowns of pipelines by Texas energy consortiums

[citation needed]

 

[strollin]

Lowered voltage, as in a brown out, causes - low voltage. The ripple in the power supply doesn't get worse due to lowered voltage. Ripple is a factor of how well the AC that has been rectified to DC is then filtered to remove any fluctuations in the DC output.

Brown outs are most dangerous to devices with hard working motors such as air conditioners, refrigerators and the like because as the voltage goes down the motor needs to draw more current to keep going which causes the motor to overheat. A computer PSU will shut down when the input voltage gets so low that it can't maintain it's output any longer.

 

[PP Mguire]

I know what both are very well, and brown outs cause heavy ripple because of the lower voltage being fed to the PSU causing a heavy fluctuation in DC output. Lower quality PSUs do not shut down, they try to keep going giving your components much less power causing damage. They are so cheap because certain functions are left out like circuitry that cuts power to the PC when AC input gets below 110.

It isn't just motors, it is any form of electronic with switching devices or heavy current users. For instance, my PA amps if fed less than 110 has to work even harder and if I am pushing them during a concert and my amps fall below 110 they could easily blow. They don't have anything to shut them down when voltage drops below nominal levels. That is why I ran Furman power conditioners with meters in the front that tell me how much I'm getting off the wall. (Newer Crown, QSC, and Mackie amps shut down now, but my amps were older)

 

[soarwitheagles]

[citation needed]

Ok Professor Jason:

California electricity crisis - Wikipedia, the free encyclopedia

Haven't had some one call me on the carpet for citations since my days in university!

I think you are speaking of black outs where the power gets completely shut off. Last time we had that here was winter of 2011 during the stupid ****ing Super Bowl. It was below 20f here and all the rural areas had blackouts that lasted over 10 hours a piece. It was snowing, icing, and many many many people had no power, heat, or hot water. Friend of mine had a new born at the time too. SO many people were ****ed and there was a huge protest and everything.

A brown out is when the voltage has a severe drop in power, not completely off. Brown outs can come from a drop in the grid from somebody ramming their car into a pole, something happening to a main line, or even severe weather catching crap lines making your power dim out.

On the subject though, black outs and power loss can also damage your electronics. When the power comes back on it is technically a surge because it is a huge rush all at once. Whenever the power goes out from a storm or black out make sure to turn off your surge protector until the power comes back on.

PPM,

No, they were brown outs. When weather conditions got really hot, the regulators shifted into a brown out mode here in California. I remember all the lights really dim, A/C would not work, and everything was really, really dark. At the time, I had no clue that this could damage the components.

I also saw the brown out's played out in Pakistan during monsoon season nearly every day. One year, it was 121 degrees F daytime temps in the shade for 30 days in a row. Most of the time, in rural areas, they shut down all power. Over 5,000 people died. My team and I had to take several salt pills every day just to survive. I remember after sitting down for only a couple of minutes there would be a puddle of sweat left on the ground every single time. Also, after two hours, not one thread of clothing worn was dry, but drenched in sweat. That, my friend was hot.

I also remember we had to use voltage stabilizers on all electronics...the flucuations were so huge and so consistent, nothing was safe. It was the same in the Philippines. Everyone that was half way educated used the voltage stabilizers. I would say we in the USA have a very healthy power grid compared to some of the other nations in the world.

Soar