I think In the actual built circuit shown as picture posted, the star contactor is connected to the thermal overload terminal from motor side, which is more safety may be, not from delta contactor side as shown in power circuit diagram.
thanks for your schematics
i made the start delta control circuit in fluid-sim, and i releized that it repeat the cycle when you press the start button again, and as solution i suggested to energize the main contact first.
Wiring connection reference will be near the terminal box of motor or the terminal box cover. This circuit is concept of star start delta run motors. Main supply will be connected to U1, V1, W1 and the configuration of star or delta will be based on the active contactor. Timer is to delay the turning off of the star contactor and delaying the turning on of the delta contactor. But what if the voltage of start is different from the run voltage?
Star-delta-timer to automatically start Star-delta. KLIBO Star-delta-timer is especially designed to start Star-delta squirrel cage motor. Starting times can be adjusted for the particular application. All further switching sequences are time optimised and are controlled and monitored by watch-dog. The output signals for star and delta are switched by powerful relays.