Which fuse to choose?

Question

Electronics

Hello everyone, such a question.
Which fuse to choose to protect the branch of the electric motor 2kW rated current 4.8A i start 5.2. Start conditions light 380v.
This is something like a laboratory, who will tell? here?

Answer 1

10A put and don't rack your brains :)

Answer 2

Well, you already know the currents, it is logical that you need a fuse for more than the maximum operating currents. Although, the correct fuse does not burn out immediately, that is, in principle, you can put it on those same 5.2 A and it will not burn out at the first start. Yes, it can only burn out next time, so it’s better to set it a little higher, because its task will burn out during abnormal operation, and there the current will be higher.
In general, the correct answer is that the fuse must be at least 5.2 A.
PS Re-read the question, okay, a typo - "protected" , but "light 380v" is some unknown crap. And get used to using the correct notation:
V - volts, I - current
"units" are separated from the value by a space, i.e. - 380 V- correct, 380V - not
in numerals - decimal point, not point

Answer 3

Maybe put a three-pole switch on the engine??
more expensive, but much more convenient?? yes, better performance

Answer 4

1.5 * Inom., for example.
For water, you can add something from the PUE, chapter 3.1, for example.
3.1.4. Rated currents of fuse links and setting currents of automatic switches used to protect individual sections of the network, in all cases, should be chosen as low as possible according to the rated currents of these sections or according to the rated currents of electrical receivers, but in such a way that the protection devices do not turn off electrical installations during short-term overloads (starting currents, process load peaks, self-starting currents, etc.).
3.1.9. In networks protected only from short-circuit currents (not requiring overload protection in accordance with 3.1.10), with the exception of extended networks, for example, rural, utility networks, it is allowed not to carry out the design verification of the multiplicity of short-circuit current given in 1.7.79 and 7.3.139, if provided condition that in relation to the long-term permissible current loads of conductors given in the tables of Ch. 1.3, protection devices had a multiplicity of not more than:
300% for the rated current of the fuse fuse;
You get a plug from starting current up to 3 * Inom.
This is from the fact that it takes a couple of minutes to be ...
And, as already written, it can look towards more advanced devices.