What is a Residual Current Device (RCD)? and how do they work?

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Күн бұрын

Residual Current Devices, or RCDs, are an essential form of protection for most circuits in modern electrical installations. In this video, we explain how an RCD works and the protection they offer to electrical installations and the people who use them.
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00:00 Schneider circuit protection series
00:20 What is a residual current device (RCD)?
00:50 What protection does an RCD provide?
02:06 Electric shock protection
03:20 How does an RCD work?
04:30 Where are RCDs used?
04:50 Fault protection with RCDs
06:30 Using RCDs with TT earthing systems
07:50 RCBOs
09:29 Different types of RCD - AC, A, B, F
10:16 Special electrical locations
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Пікірлер: 41

@sergiofernandez3725 10 ай бұрын

Very informative. It's always to good learn something new on a regular basis.

@alanmainwaring1830 7 ай бұрын

In the diagram you show a toroid transformer with two windings. One winding in the live line and the other in the neutral line. First this would lead to an increase in resistance. According to Amperes law if you had a winding encompassing the entire line and neutral pair when the currents are equal in both lines no induced power will be picked in the outer coil. Think of the clamp meters you only put it around one of the wires. With AC you could put quite a few turns around the pair and thus increase sensitivity without affecting the source impedance. With DC all I can think of is a Hall Effect device. I was trained in the Electronics field. Still puzzled how these devices actually work.

@Dharam_Neeta_vlogs 7 ай бұрын

Good job

@Enrx90 10 ай бұрын

Thank you so much for the video question… Can I wire the rccb from bottom to top ? And does it matter the direction ?

@richardhince9764 10 ай бұрын

I think terre-terre is French, Latin for earth is terra if I recall my Latin classes well enough. Also other earthing arrangements such as TN-S, TN-CS are also French. For whatever reason.

@TheManLab7 10 ай бұрын

Well it was harnessed in Italy by Alessandro Volta.

@GRAVEAUDIO 10 ай бұрын

I'm french and - you're right

@IAmThe_RA 5 ай бұрын

But it is terra-terra. Terra is how you say Earth in Portuguese and Italian (and Latin). Nothing to do with the French language.

@tomclarkson3759 8 ай бұрын

Please do a video explaining how earthing works on a 240v inverter in a work van. hypothetically, imagine there are at least two appliances with "earthed" cases, like a microwave and kettle. There is a lot of conflicting information online about earthing to the chasis, or having a earth rod, in which cases would protections devices work or not. thanks!

@alanmainwaring1830 7 ай бұрын

This is a tricky area, If you are running your van say from a Campsite power system no need to use a ground rod. As long as the entire chassis is connected to the Green/Yellow wire. Of course you are relying on the campsite source having its own RCD system. For extra safety get an external safety outlet the plug your extension cord into that. In my van I have backup battery's running a 3000W DC to 240AC inverter which interfaces to a mini switch board. The inverter is bonded to the chassis and power goes through a special RCD breaker. As you say you get so much conflicting information make sure all you're wiring is in really good condition. By the way my only interface to outside power is a 70 amp battery charger and solar.

@Dog-whisperer7494 10 ай бұрын

Great explanation Joe 👍 And I agree with someone else’s comment Tera if French Latin meaning earth. But why French Latin why not English Latin? Fantastic video as always Joe

@user-tw8fg4mk5v 5 ай бұрын

Please, what is the name of the book from which you were reading the specifications of the electric cutter?

@firealarmwizzer9026 7 ай бұрын

There is a device available to protect from electric shock from live to neutral if the mains voltage was 12 volts the same as a 12 volt adapter instead of 230 volts.

@temp06j723-pmeighttq 6 ай бұрын

Say you stepped on a raised metal platform that is insulated against Earth & it has accidentally cut into a Neutral wire near the wall. Then you are barefooted on the platform & perform an amateur fiddling of extension cords wiring and come into contact with one Line energized parts. (Both this Extension cord & Neutral fault of raised platform is of same RCD.) So you will receive your electrical shock without the RCD noticing anything amiss.

@mikethemask1525 20 күн бұрын

Can rcd/rcbo operate from a fault upstream and downstream of it.

@user-tw8fg4mk5v 5 ай бұрын

Are The RCD need to wire Earth for the work?

@mdtaj3507 10 ай бұрын

👍

@ktgohdt125 10 ай бұрын

Do RCD act as MCB when a direct short either L to N or L to E???

@okaro6595 9 ай бұрын

No, they do not have overcurrent protection.

@ktgohdt125 9 ай бұрын

thanks@@okaro6595

@temp06j723-pmeighttq 6 ай бұрын

A Dead-Short of L-E is considered Earth Fault and will ultimately Trip any RCD as intended. An RCCB, subjected to a L-N short-circuit may Not trip the RCCB. But due to the Sudden Imbalance at the Sensing Coil due to the Dead-Short, sometimes it may trip the RCCB. As for RCBO, when subjected to a L-N short-circuit, it will Trip due to the overwhelming at the Magnetic Coil that reacts to Short-Circuits.

@Mainly_Electrical 2 ай бұрын

Subscribe @mainly electrical to learn

@gadgetman36 11 ай бұрын

The end card links to AFDDs, not SPDs, and I can’t find the SPD video.

@efixx 11 ай бұрын

Updated to correct link

@gadgetman36 11 ай бұрын

@@efixxIt's still linking to AFDDs.

@djoakeydoakey1076 10 ай бұрын

This video came out 3 hours ago. Are you all time travellers?

@TheManLab7 10 ай бұрын

When it comes to a TT systems. The meter tails go straight into a 30mA RCD and then into the D/B's.

@paulmatthews5470 10 ай бұрын

Yowza let's hope nobody plugs anything dodgy in otherwise you lose the entire install

@intercity125 10 ай бұрын

100 mA type S on the front end for TT with normal type A 30 mA downstream no...

@paulmatthews5470 10 ай бұрын

@@intercity125 and make sure the downstream RCDs are double pole, speaking from experience. 😬

@TheManLab7 10 ай бұрын

@@paulmatthews5470 it does unfortunately. This is why I tapped off the incoming side of the RCD and put a dual RCD in the shed so when something trips out there, it doesn't take the whole house out. Every time I take a supply from a DB and put another board in, I never put it on one of the RCDs incase the other board trips and takes out everything.

@Mainly_Electrical 2 ай бұрын

@MAINLY ELECTRICAL .. to learn boys and girls

@rocketn8 10 ай бұрын

An RCD is either: What he said.. Or... A box of SunMaid. Who remembers? Who's with me. Also. What is the breaking capacity of a box of raisins?

@Cymaphore 10 ай бұрын

Something I miss in the video is a very fundamental difference in the way RCDs can be build. There are electronic as well as electromechanic RCDs. Why does it matter? While electronic RCD mechanisms can be built small and quite cheaply, they are absolutely dependent on the presence of a voltage supply and wiring direction and are much more volatile to surge damage and interference. For example, if the neutral or pen is absent or supply is unstable, it is unable to operate properly. Electromechanic mechanisms are much more reliable, but they are bulky. They will trip when there is a current imbalance, regardless of the voltage. You can even trip them when feeding 100mA with a lab supply on the neutral path (switch it on / off a couple of times). Electronic ones are completely blind in the absence of stable supply. While the size issue doesn't matter for "traditional" RCDs (sizing 2 to 4 modules in width), until recently this was a huge issue for compact RCBOs. And that's where there is a fundamental but little known difference between uk and germany. In britain, electronic RCBOs took over the show completely, especially due to the tiny size of british consumer units and lack of space therein. In Germany, electronic RCDs (except for flat DC detection mechanisms in type B units) are forbidden by the standard and only voltage independent ones are allowed. Until recently that had the very unattracktive sideffect that RCBOs generally took up at least 2 modules in size each. But now there are two manufacturers who managed to size the mechanism down, namely Siemens 5SV1 and the ABB DS301C. Might be an interesting topic for a video for eFIXX to have a deeper look at?