ACS800 motor overload function
We are using ACS800 (approx 3000 A) VFD for motor (rating- 690V, 1160 kW, 1210 A, 993RPM). Our application is rotary kiln (cement plant).
Our current limit in the drive P20.03- 2700A.
How will the drive react, if the motor current is continuously running above its rated 1210A ?
Will the drive generate any overload tripping & after how much time if the running motor current is above its rating 1210 A?
What is the motor safety in the drive if motor current is running continuously above its rating (1210 A?
in my humble opinion, I would be concerned that the motor absorbs a higher current value than the one stated on the plate. This means that the torque required by the load to the motor is higher than that on the nameplate / characteristic of the motor itself, probably an index of mechanical overload.
The drive behaves according to what it is told to do: if its current value in parameter 20.03 is 2700 A, up to that value the drive does not understand that there is an overload in progress and therefore I doubt that it can intervene in any way. In a nutshell, and since I have no other information on the system, in my opinion you risk burning the electric motor.
To give some other advice, I should analyze the entire programming of the drive, I recommend instead of having the nearest ABB Service intervene and ask them for the necessary support to correctly calibrate the drive.
However, there is no doubt that the absorption of this motor is not correct, so there is something wrong with the load of the electric motor, or in the mechanics of the rotary oven, in my opinion.
Nothing more to add to Flavio's answer.
Usually the current limiter is set less than motor's nominal current (99.06). The intention is to limit the current/speed if the load "wants" more current than the motor can provide (eg pump or mechanism is over-sized).
In case of heavy start, the drive have to manage the overload - you select the drive using heavy duty load values, and that is all. May be small adjustments in torque limiters, but not the current limiter !
If you are talking about protecting functions to the motor (thermal protection), you have the parameters 30.04...30.07.
I can recommend you to ask a competent drive support for advise how to adjust the drive.