IT equipment

[sparks1234]

Also with reference to my previous thread, we are all aware of the use of a functional earth when it comes to IT equipment in an office enviroment.
Normal PC's have a power supply inside them so surely they have no use for earth, does this really refer to the old CRT monitors which are basically extinct now?

 

[sparks1234]

Submitted this once already but it disappeared.

IT equipment (as in office pc's) is rumoured to use earth as functional. therefore requiring a high integrity earthing system.

PC's are run through an internal power supply, does this leak to earth?
Monitors are generally unearthed these days being double insulated, the old CRT monitors probably had a leakage.

My question is, do PC's actually use earth as fuctional and if so what would the typical leakage be?

 

[bugsy]

all this depends on the installation, to determine the degree of protection, are the earth leakage currents below A 3.5m/a , B.above 3.5m/a but below 10m/a or C above 10m/a

 

[sparks1234]

all this depends on the installation, to determine the degree of protection, are the earth leakage currents below A 3.5m/a , B.above 3.5m/a but below 10m/a or C above 10m/a

Thats my question, generally I am asking if normal desktop PC's actually have an earth leakage

 

[bugsy]

The earth leakage comes from the mains filters and is typically between .73 and.145 m/a

 

[fuse]

The earth leakage comes from the mains filters and is typically between .73 and.145 m/a

Do you mean earth filters within the switch mode power supplies ?

 

[bugsy]

If your doing an IT installation this may helphttp://www.------.org/publishi...7earthing.cfm?type=pdf

 

[bugsy]

Re: Functional earth

All P.Cs have mains filters using capacitors, these wiil create earth leakage - see previous post on I.T,eqpt and follow the threads

 

[Darkwood]

Re: Functional earth

Most modern day electronics run off the mains supply at some point and which if just transformed and rectified would be full of 'noise' which in some cases is just annoying and others can be harmful to the hardware itself, filters are usually fitted which help smooth out the waveforms and also dump unwanted noise to earth whether it be mains transients or the waste from the chopped up a/c supply.

 

[uksel]

Yes IT equipment does use the earth functionally, and it will have some earth leakage (though this should be minor).

I believe this is due to electronic equipment being sensetive to static, therefore the earth is used to discharge any static in the system and avoiding any damage to the equipment.

feel free to correct me anyone if i am wrong

 

[Darkwood]

Yes IT equipment does use the earth functionally, and it will have some earth leakage (though this should be minor).

I believe this is due to electronic equipment being sensetive to static, therefore the earth is used to discharge any static in the system and avoiding any damage to the equipment.

feel free to correct me anyone if i am wrong

Static only exists if a potential exists but has no real energy so general earthing would omit this issue, check my last post to get an idea why the earth is funtional at discharging noise.