ATS22C11Q and line contactor 3-wire control

[KanG]

I have a softstarter ATS22C11Q and I want to control it with a three-wire circuit - with start and stop buttons .

From the point of view of reliability, I want to connect it according to the scheme indicated by the manufacturer (on the picture ).  There are 4 buttons on the diagram.

In what sequence are they pressed when starting and when stopping (how does this scheme work)?

How to make contactor KM1 turn off when we press stop.

What must be the power of transformer T1  (400/230V) ?

[BJacqz]

Your electrical drawing is correct, in order to initiate the sequence, S2 must be pressed on, it will allow KM1 to supply the starter, then S3 will initiate the motor starting with settings you entered in the Soft Starter (I mean ramp and current limitation). Stopping the motor can be done using S4, in this case it will follow deceleration as programmed in the soft Starter, but it can also be pressing S1, in this case the KM1 will open then motor will stop on freewheel. The power transformer has to be in accordance with all your sequnce components (KM1 coil plus CL1/2 consumption, advise to 100VA, add eventually fan if necessary depending on your duty cycle (see manual for this last topic).

[KanG]

Thanks for your reply! To simplify the control, I decided to use the scheme with 2-wire control . I will use only two buttons - S1 and S2, with which I will control the linear contactor KM1 and with its normally open contact I will control the softstarter (instead of S3; to Li2). I hope the delay of the softstarter start command compared to pressing the S2 button is enough to avoid an alarm message. Li2 -> "run" , R2->"trip"  value. What is the difference in setting "trip" and "alarm" of relay R2 (or R1) - how much do the activation cases in the two modes overlap?  There are no detailed descriptions of the relay settings in the softstarter manual. Thank You!

[KanG]

P.S. Freewheel stop (deceleration is off and not used).

[BJacqz]

The difference between trip and alarm is an alarm will only indicate there is a potential stop of the device, a trip will stop the device. As indicated, in the user's manual, "the alarm will indicate the presence of a non critical event" (example of thermal pre alarm coming before the thermal trip detection occurs). Hope this helps you...