The following circuit comprises of NodeMCU (ESP8266) which is intended to run a 200 RPM johnson motor. The circuit comprises of 5V Relay connected via Darlington pair using transistors. The circuit is powered by 12V, 1.3A battery through a 7805 Voltage Regulator.

Circuit Info: Transistor: BC547, Resistor: 120 ohm, Cap/Capacitor: 0.33 muF

The circuit runs the motor for few seconds and then turns OFF abruptly. Please let me know if there is an error in the circuit or any power circuit need to be additional put.

Nodemcu and Relay circuit

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    \$\begingroup\$ You need to supply a schematic, not a PCB layout. Make sure you turn off the grid before taking a screengrab. \$\endgroup\$ – Transistor Feb 2 at 13:37
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    \$\begingroup\$ Also, debugging. Does the logic output from the MCU turn off? Has the MCU watchdog triggered? What software debugging have you done on your control program? How hot is the 7805 getting? \$\endgroup\$ – Brian Drummond Feb 2 at 13:53

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