Help with wiring three phase pool airblower

[elector]

hi.
one of the electrition in our company tried to wire a three phase pool air blower {in star connection}.
when he connected the three phases to the air blower after one minute the air blower coils were burned.
the thing is before that there was another of one phase air blower and it was workung fine.
the three phases that goes from the panel are 1.5{mm^2}.
so the man connected each one of them to the three terminal at the air blower(to W1, U1, V1}
after a minute the coils were burned in the air blower.
i'm kind of new in that business so i trying to think what is the problem to learn more.
the three phases goes through a circuit breaker to contractor and then to the air blower.
maybe we need to put three phase circuit breaker?
in the picture you can see the burned cables.
the power of this air blower is 2200 watts and the three phases giving together 380 volts.
that means that the current that goes in the three phases is (2200\380= 5.8A}?
and by that i need to choose the circuit breaker?
thanks.

 

[Andy-1960]

Do you have a photograph of the motor plate?

 

[westward10]

Has the motor burned out?
Did the mcb trip?

 

[Pete999]

How did he wire the motor in star? there doesn't seem to be any links on the motor winding ends, is it a DOL start motor?

 

[westward10]

Looks like there is a star link Pete.

 

[Pete999]

Looks like there is a star link Pete.

You're right Westy I need some new specs

 

[Marvo]

hi.
one of the electrition in our company tried to wire a three phase pool air blower {in star connection}.
when he connected the three phases to the air blower after one minute the air blower coils were burned.

A simple on-load current test of all the phases would have shown it was overloaded and it could have been switched off before it was toast. Also a correctly sized thermal overload would have saved the motor. Your company electrician needs to up his game.

....the three phases goes through a circuit breaker to contractor and then to the air blower.
maybe we need to put three phase circuit breaker?

Are the three phases on three separate single pole MCB's? Yes it should be a triple pole, you want all three phases to trip or reset simultaneously.

in the picture you can see the burned cables.

Yes, alas I can. That motor was unnecessarily destroyed.

the power of this air blower is 2200 watts and the three phases giving together 380 volts.
that means that the current that goes in the three phases is (2200\380= 5.8A}?
and by that i need to choose the circuit breaker?
thanks.

No. Firstly the circuit breaker is designed to protect the circuit that supplies the motor, not the motor itself. Size the circuit breaker according to the circuit wiring and installation method. You need to fit a thermal overload or manual motor starter to protect the motor.

The 2.2kW rating of the motor refers to the amount of mechanical work it can do, not its electrical consumption. Use the current rating given on the info plate or refer to manufacturers specs for the max run current and use that to size the thermal overload.

Also incorrect rotation direction can cause the motor to be overloaded depending on what type of bladeset the blower has so check rotation also next time. Obviously rotational speed must also be correct so check the rpm of the original motor

 

[telectrix]

looks like help is required with directions to the nearest skip. EPIC FAIL.

 

[Specialist]

Nicely toasted, that was an expensive mistake to make.