What to choose? RCD or Differential Automatic

n1. Reserve space should always be.

n2. The only comment worth paying attention to

p3. Absolutely disagree. It all depends on the manufacturer, it is often the opposite - combined devices are more reliable.

p4. The resource of an automaton or ouzo is 6-10 or 16 thousand cycles. Failure depends on product quality. Again, this is a matter of choosing a manufacturer.

p5. Installing bugs? original.

p6. If you observe the "selectivity", then the dispute is not clear about what.

p.1: "The differential automatic device takes up less space in the shield than the protective shutdown device" - complete nonsense !!! What is meant by a differential automaton? Of course, an RCD with the function of protecting against overload currents and short circuits, and in the RCD itself or in another differential relay there is no this function and most importantly, among the manufacturers revered by the manufacturer, there is no difference in size, they are either 2 pole or 4 pole !!!
Clauses 5-6 are generally utter nonsense. It seems that the author who drank a little wrote an article ...

Read the article more attentively ... Places are exactly what happens more often, what is lacking for many reasons, either the customer will buy the wrong shield, or they will be equipped with additional devices, etc.

And now!!! Pick up a bipolar diffavomat and pick up a bipolar RCD + single-pole circuit breaker. Question! What takes up more space ??? I think everything is clear here.

Apparently people who comment on this post are far from wiring.

And where does selectivity (selectivity), if the author writes about the reasons for disconnection - how can a simple consumer understand for what reason this or that switching device has disconnected.

I will say a word from myself. This article deserves attention. I completely agree with the author.

It seems to me that the author is far from installation and design.

If you observe selectivity, then the difavtomat will not work on overload, but the outgoing line machine will work after it.

Of course, there are "projects" where one (or maximum two) "switch" (automatic) is designed for the entire object. But it is better when the object is divided into parts that are powered by separate machines (if in a nutshell))).

If the customer is stupid and buys the wrong shield, then the difavtomat will not save the situation))))

Chaotic article. Absurdity in the title of the article. According to the PUE, either differential.an automatic machine, or a circuit breaker and an RCD, since the RCD does not protect against short circuits and overloads. A differential. the machine in itself contains the functions of both the machine and the RCD.

Elvira, don't be smart.

Everything is written right here! I completely agree with the author of the article.

The author is right, and pseudo-electricians are wrong.

Respectosis to the author! Everything is correctly and clearly stated! Dissenting commentators - learn the mat. part!

Thank you for the article. Today I ran into this dirty trick (differential author), it is cut down by xs because of what, I did not understand the principle of its action and how to look for a problem. By the way, I read that there is still a load switch with differential protection, apparently these are different devices (although they look similar in appearance).

the sweetest thing is that wikipedia does not see the difference between an RCD and a differential machine ...

“If for some reason the differential automaton has turned off, the reason for disconnecting is UNKNOWN” - dear author, but what about the Schneider Electric diffs, they have models with two flags — when triggering a differential, you can understand the reason for the triggering, judging by one the flag has flipped back, or both at once.

Cool! I’m preparing the house for winter — today all day on the web I’ve been looking for the best connection option 380v. to an electric boiler (or ouzo, or dif., or Ap + ouzo). It was already decided and came across this article, which turned all plans upside down. And one more thing: all the “throws” in the author without taking into account the specific model of the situation-emotions that have a place to be. That's all. I liked the article. Thanks.

Very interesting article. It turns the very concept of ouzo and differential protection.
Ouzo device of protective shutdown. It is clear that it protects against electric shock. But what is the principle of action? Edward is right. There is no difference between the ouzo and the differential automatic. It will not happen even if the ouzo works from a dangerous increase in voltage between the non-current-carrying parts (cabinet body) and the ground. In this case, the cabinet is not earthed, but a voltage relay is installed between it and the ground. This is also ouzo. Dif protection (differential transformer) is one of the varieties of the principle of operation of the ouzo and several of these varieties. You need to think not about the place in the closet, but about the safety of people. The author was thinking about whether to combine the protection and overcurrent protection in one housing (two modules) or to separate them in different places (three modules). I think here the question of the laboratory about the ratings and speed.

Your desires will not be able to come true in "life" for a simple reason - lack of space in the shield.

Uzo (aka a differential switch) cuts off the load if the difference between the zero and phase currents exceeds the value of dI.

Dif (it is a differential automaton) performs all the functions of a narrow, plus has protection against overcurrent and short circuit

Total:

Ouzo = RCD

Dif = RCD + automatic

If we compare that Dif or RCD is better, then Dif automatic is better, since it combines the functions of two devices at once, and this is convenient!

I don’t understand what the argument is about! People either did not read the article or were not competent.

Yes, just all such topics are needed only by specialists (master class) or beginners in this field (manual). All other inhabitants are unnecessarily.

I agree with the author and do not agree with my partner, an electrician with many years of experience))

Yuri, what do you disagree with your partner?

I came across a topic by accident, I don’t see the date, maybe it’s already closed.I’ll leave my opinion, maybe someone will be interested - for protection you need to use only RCDs functionally independent of voltage (example VD1-63). This is the main thing. Only then all the bells and whistles in the form of a single unit with an automatic machine over currents, or different elements. I have not seen (on a regular sale) differential machines without the use of an electronic leakage control circuit - this means they have power, operating hours and unreliability. And what kind of power will the circuit have when zero is lost? Itself repaired the circuit when, when the contact was oxidized, a similar electron diff. the machine continued to freely skip the phase without reacting to the connection of an external load according to the leakage circuit. In mechanical, voltage-independent, RCDs are not possible! This is not about praising a specific VD1-63, but about the principle of operation. We still choose from the inexpensive ones available for sale.

Paragraph 2. quote "... Due to the increased load (power), the differential circuit breaker will start to shut down due to overload and it will have to be replaced with a higher rated current. In the case of an RCD, you will only need to change the circuit breaker."
Strongly disagree: replace the circuit breaker (conditionally 25A by 63 A) and you will have an unprotected RCD, which is designed for 25A in this example

I want to add on the sixth point about the reason for the shutdown. There are some types of differential machines in which there are two LED indicators that indicate the reason for the shutdown of the protective device. That is, during a short circuit or overload, one LED lights up, and when it is turned off as a result of a current leak, another LED lights up.

Well, even if there are no indicators, then, I think in most cases, you can easily determine the cause of the operation of a differential automaton. For example, when the next electrical appliance was turned on, after a while the differential automat turned off - that means there was an overload. In this case, touch the case of the disconnected diffuser: if it is hot, then the excess of the rated current was clearly the reason for its shutdown. If, after turning on the household appliance, the device instantly shuts down, this may indicate a short circuit due to damage to this household appliance. Disconnect this appliance from the mains and turn on the disconnected differential machine. If there is no repeated shutdown, then the appliance is really damaged.

If, for example, one of the electrical appliances, for example, an electric furnace, has been “pinching” a little lately, then it is highly likely that the differential circuit breaker has turned off due to current leakage through the damaged insulation of this electric furnace. You should also pay attention to the contact connections of the conductors in the intermediate junction boxes. Very often, unreliable contact connections cause current leakage and, accordingly, disconnect the differential circuit breaker.

If you do not use cheap diffavomats and prematurely make a project for the electrical part, and make a quality installation of electricity, then there will never be any problems.

according to claim 2
<< Due to the increase in load (power), the differential circuit breaker will start to shut down due to overload and it will have to be changed to a higher rated current. In the case of an RCD, you only have to change the circuit breaker. >>
The RCD must be designed for a larger current than the machine standing after it. RCD - 25A, automatic - 20A. So changing the machine, you have to change the RCD. But of course, if a group of 4 automatic machines of 16A each has an RCD of 80A, then a couple of automatic machines can be replaced painlessly. Just choosing an RCD or differential.automatic, you need to look at a specific scheme.

I read the article and the comments and partly agree with the author, but there are comments on paragraph 2. "Quote": Due to the increase in load (power), the differential circuit breaker will start to shut down due to overload and it will have to be changed to a higher rated current. In the case of an RCD, you only have to change the circuit breaker.

Think for yourself what’s cheaper - differential machine or circuit breaker?

No one has mentioned that not only people and equipment are protected, but also email. network if we are talking about 25 And then according to the PUE of table 1.3.6 you selected a cable with a cross section of 2.5 mm (in the air) and if you zelenen a differential machine or circuit breaker to the next one at a nominal value of 32 A, then the wires will simply start to burn. True, if you do not take this into account as the author sees it, then of course you can do without protection at all :) (joke).

Write your article, critics.

Dmitriy,
You have a normal article, but it requires refinement and expansion of the conditions for choosing a device. The critics did their useful work - they added details.

In conclusion, I’ll add that there are a lot of small nuances for specific conditions that no one can take into account - only a good specialist with experience.