Choosing Differential Protection: One for 3-Phase or Individual for Each Circuit?

I am reworking the installation in an old house and I am asking for advice from more experienced people. In the 3-phase distribution box, I pull 3 circuits, the expected load is approximately equal, and therefore the question is whether to use a differential 1 for 3 phases - or for each circuit separately 1 ph.?

Install one 3-phase differential on the rail and right next to it, three single-phase differentials. Connect three phases to the three-phase differential and, at the same time, from the same terminals, connect one phase to the other three differentials. Connect all differentials to the bottom with S-type protections. three-phase security, send the cable to the basement and garage where you will power all receivers and even a three-phase water heater. From the other single-phase security devices you can power the receiving sockets from one of the other, lighting, etc.

Hello

I would use three RCDs or RCBOs. If you use a 3f RCD to supply three 1-phase circuits, it will trip an RCD in the event of a fault (leakage current) in one of the circuits, which will also disconnect the non-faulted circuits.

If you would install one differential for the whole house, darkness will envelop the whole house during its operation.

>> Kierbedz4

What is the function of a 3-f before 3 1-f? Unless the "main" device would have a different (larger) trip current, eg ?I = 500mA, as a fire protection. But you didn't explain that in your post. Regards

Kierbedz4 he wrote:

Quote:

Install one 3-phase differential on the rail and right next to it, three single-phase differentials. Connect three phases to the three-phase differential and, at the same time, from the same terminals, connect one phase to the other three differentials. Connect all differentials to the bottom with S-type protections. three-phase security, send the cable to the basement and garage where you will power all receivers and even a three-phase water heater. From the other single-phase security devices you can power the receiving sockets from one of the other, lighting, etc.

The author wrote:

Quote:

In a 3-phase distribution box, I pull 3 circuits

And:

Quote:

1 for 3 phases - or for each circuit separately 1 ph.?

What is the conclusion of this? That colleague Kierbedz4 writes nonsense! He sped up like a locomotive down the hill ...

Question to the author - what is the nature of the load (lighting, sockets, and maybe something else?)

Read on. 3-phase differential + S type protection garage or instantaneous water heater, hydrophore, welding machine and other three-phase circuits in the garage. Other power supply protected by single-phase differentials not connected to the three-phase differential! with installed S-type protections to protect the remaining circuits.

If there are any other 3f devices at home, it is a 3f differential, if not it is cheaper 3f but better 3x1f.

if there are receivers 3f, then and these circuits must be differentials3f on receivers 1f differential1f

Kolego Akrzy74 take it easy, what is this nonsense written by my colleague Kierbedz4? Three-phase pick-ups require a three-phase differential, and the others one-phase. The installation designed in this way is redundant, the leakage in one phase does not completely deprive the house of AC power. The proposal of my colleague Kierbedz-a4 is correct!

Hello

Yeah, well described, but there is also something like selectivity. Nobody wrote about it. For the main first RCD - 100mA, then 30mA. If not, this 3-phase differential will be banging anyway

Regards

If there are no power sockets in the house or such sockets, it is not expected in the future, you can ignore the 3-phase differential (the selectivity problem will be eliminated) and install 1-phase differentials on selected circuits.

ronwald wrote:

Kolego Akrzy74 take it easy, what is this nonsense written by my colleague Kierbedz4? Three-phase pick-ups require a three-phase differential and the others one-phase. The installation designed in this way is redundant, the leakage in one phase does not completely deprive the house of AC power. The proposal of my colleague Kierbedz-a4 is correct!

I agree that it is correct, but forcibly adapted to the idiotic assumption of Kol. Shein48, which provided insufficient information to get a correct answer, but already has fifteen advisers.
THIS IS NOT DONE COLLABORED !!!
Do not provide information on general questions. It is as if someone stood at the crossroads of 10 roads and asked which way to go. You can answer freely, any direction will be correct. But is that the point? After all, man certainly does not know any of these answers.

Col. Ronwald- I am calm I understand it like this:
The author wrote-

Quote:

In a 3-phase-pull distribution box, 3 circuits are expected to load approximately equal

So: 3-phase power supply, 3 single-phase circuits were made. Why 1-phase? Bo wrote that the three new circuits will have approximately the same load.

Quote:

and therefore the question is whether to use a differential 1 for 3 phases - or for each circuit separately 1 ph.?

Here the author asked a clear question: a 3-phase differential for these 3 new circuits, or maybe 3 independent 1-phase ...

Kierbedz4 wrote in one of his posts:

Quote:

Install one 3-phase differential on the rail and right next to it, three single-phase differentials. Connect three phases to the three-phase differential and, at the same time, from the same terminals, connect one phase to the other three differentials. Connect all differentials to the bottom with S-type protections. of the three-phase protection, send the cable to the basement and garage where you will power all receivers and even a three-phase water heater. From the other single-phase protections, you can power the receiving sockets from one of the other, lighting, etc.

-It is not known how much space there is in the switchboard
-It is not known whether there is e.g. FR in the switchgear
-It is not known whether the author has a basement and garage and whether he intends to modernize something there, and if he has, if he has an installation prepared for rcd ... (in this basement and garage, which the author did not mention)
-Since there is speech just about three 1-phase circuits, why "czorta" write about additional rcd, other circuits - which may not exist at all
-If you think this way- (i.e. from momentum), it might have been necessary to recommend grounding, equipotential bonding Main and local, installation of the limiter. overvoltages, LS, etc ...
Kierbedz4 wrote:

Quote:

Read on. 3-phase differential + S type protection garage or instantaneous water heater, hydrophore, welding machine and other three-phase circuits in the garage. Other power supply protected by single-phase differentials not connected to the three-phase differential! with installed S-type protections to protect the remaining circuits.

Where did the author (in his first post) mention a garage, hydrophore, welding machine, or other circuits?

Anyway, even here, one should consider the advisability of using one residual current device (not mentioned the rated current - which is important) for a water heater, hydrophore, welding machine, and other circuits (?)
That's why I wrote:

Quote:

What is the conclusion of this? That colleague Kierbedz4 writes nonsense! He sped up like a locomotive down the hill ...

The answer should be short and rather unambiguous,and a little more, it will be a paper "Which side is the phase in the hole", or another - with a similar degree of difficulty ...

I am only asking for one thing - do not write down unnecessarily . Kierbedz4 mentioned a 3-phase and 1-phase rcd (connected in parallel), and here it is already about selectivity, about a 100mA rcd and that something will "bang" - I wonder what can be banging in the switchgear? (Maybe Mrs. Shein48 of Mr. Shein48 on the head, as the 3-phase RCD will turn off the 1-phase circuits and the cake will not bake). It is enough for the topic to refresh, and there will always be someone who does not read and write thoroughly. There are really many topics where the answer can be given in several posts, and ends with a several-page paper - because the topic becomes multi-topic.

Ps. I don't expect an answer.

Akrzy74 wrote:

Ps. I don't expect an answer.

Col. Akrzy74!
It was still necessary to summarize: there is no technically good answer to such an undefined question, because there are so many conditions that every hint may be wrong.

As colleagues wrote, the use of three RCDs has the advantage that triggering one will not cut the voltage on the other phases. But on the other hand, it is important to answer the question of how often this circuit breaker may trip. Hence, one 3-ph can be used and in the case of 3-ph loads (motors) there must also be a 3-ph switch. How big is the apartment the author of the subject has, because if small, only 3-f would be enough.

I agree with the statement that the topic is not properly described by my colleague Shein48, the technical drawing (installation diagram) is missing from the question posed.

However, no one (almost) "thought" to even ask the "silent author":
Akrzy74 wrote:

Quote:

A question for the author - what is the nature of the recipient (lighting, sockets, and maybe something else?)

Everyone wrote as if it was a topic: "Help! Which way to screw the light bulb".

What loads may be in a typical home; single-phase and three-phase )! Let's not ask questions like whether the water is wet? In my opinion, the energy balance and the diagram of the installation that the author intends to perform (modernize) are more interesting.

Due to the lack of interest of the author - I close the topic. If there are new facts, I am waiting for PW from the author.
[Akrzy]