Is there a continuous flow of electricity passing through the screws in a PC case?
Is there a continuous flow of electricity passing through the screws in a PC case?
The sole protective factor is the circuit's "impedance" near the 70V, which could be relatively high. Therefore, the flow of current from your hands down to your feet, through the floor, or across your torso toward another arm/fingers and a different fixture in another room, might be minimal and not dangerous. However, certain individuals are more prone to electric shock.
Considering the above remark, the existence of 70V between your outlet screws and what's called "ground" suggests one person is likely closer to actual earth potential. I can't confirm this. Your main "earth" and the outlet screws should both be at true earth potential, not separated by 70V.
I regret disagreeing with your professional's view. It might be acceptable to have somewhat floating earth connections, but they seem risky. Charging a few SAR and blaming the PSU could be a way out, even though the landlord is unlikely to fix the whole structure.
I understand your point, but if the situation is similar in another location 30km away, you might face the same issue.
As-salamu alaykum. I worked in Jeddah for four weeks and recall the flat had three socket sets per room. One outlet was 220V, another 110V, and a third was for a landline phone. I was cautioned not to connect the phone to the 220V socket by mistake. It usually lasted a few seconds on 110V but not on 220V. I never reached Mecca, but traveled up to Taif.
Returning to your concern: your Corsair SF750 PSU is not a bad build. Unless you can replace it with something similar, we won't know if the problem lies in the faulty PSU or in the wiring at your flat (and also 30km away). This remote assessment is becoming uncertain.
Could you consider borrowing a higher-quality PSU around 750W? It doesn’t need to be SFF. You could use a full-size ATX power supply, but it shouldn't be physically fixed inside the case if it won’t fit.
Given the questionable mains voltages reported by the "professional" electrician and your 70V reading between outlet screws and "ground," I still believe the issue stems from the main supply, not the PSU.
Other people in the Kingdom likely face the same problem. You seem certain you won’t receive assistance from your landlord, so I recommend seeking help from a local computer shop or qualified IT expert. They might test your SF750 or provide a new PSU.
If you're fortunate, you might find a metal beam, pipe, or conduit in your walls or outside a window (perhaps a fire escape). If this were my case and I found a good earth, I’d contact a professional to install a mains isolation transformer in my flat.
If you’ve made it through all this confusion, remember I once used a 1:1 500W mains isolation transformer to safely test old TVs. For a PC, monitor, or router, you’d need at least 1,000W of isolation. The method is to use the transformer to isolate the faulty mains and connect your PSU’s metal parts to a better earth.
It’s common in my area to install a mains isolation transformer on construction sites for power tools. The standard 230/240V AC supply is reduced to 115/120V for professional equipment, which is often double isolated (Class II), so it doesn’t require an earth connection.
Although I’d prefer a direct 1:1 (230V → 230V) transformer in your flat, it might be simpler to find a 230V to 115V isolating transformer designed for power tools. Your SF750 should work fine at 115V as well. Check your monitor and router too.
[Link to transformer info](https://www.toolstation.com/110v-tool-tr...mer/p80013)
If you can’t locate a suitable earth in your flat, a mains isolation transformer will be less practical, but it should still protect the supply. You remain at risk of electric shock if the PSU fails severely, and you can’t secure a proper ground elsewhere. Don’t rely on existing "earths" until you’re sure they’re safe.
TLDR: Seek advice from a professional IT or electronics installer for large-scale systems—not just a local electrician—before acting.
All this discussion about electrocution prevention raises questions about earth leakage protection like RCDs that could react within 20ms at about 30mA, possibly stopping harm in most situations. Where did you find that number? The typical threshold is around 50uA for an average person.
@Misgar a workaround might involve using an isolation transformer, but be mindful of any connected devices that could create extra return paths.
It is true that my house, built in the early seventies, lacks an RCD. Besides the main 100A breakers, there are no MCBs, only large porcelain fuse holders and old-style fuse wire. I’ll have to install a modern consumer unit before selling the property!
At least I avoid the troubles a friend faces. During thunderstorms, their 20mA RCD trips frequently, causing the house to go dark at night. A qualified electrician inspected the wiring but couldn’t fix the issue.
I planned to power the OP’s entire computer setup from an isolation transformer—PC, monitor, router, switch, printer, speakers, etc.
As I mentioned before, seeking advice from a professional in the KSA is essential before taking action. It could be tough to worsen the situation, but extra care is wise when working with mains power.
I’m familiar with using Class I equipment on two-pin (non-earthing) outlets in developing countries, but I can only offer cautionary advice.
The issue involves a rented property with little likelihood of any steps being taken by the landlord.
@Misgar
Has your friend considered switching to another brand RCD or emergency lighting? Here, power cuts occur frequently during thunderstorms, affecting not just one property but entire areas, and can persist for over an hour before resuming.
My friend is swapping out the old meters for a smart one to get a better rate, which could also mean updating the RCDs. Only their property is impacted by thunderstorms; the neighbors on the hill are still okay.