I’m building an cocktail machine for a school project that is using 8x perilstaltic pumps, these consist of a regular brushless dc motor.
The motors operate at 18V and 0.2A.
I want to be able to control the motors in both directions so the transistors should be able to switch a positiv collector voltage and gnd connected to the collector.
I tried this using the 2n2222 bipolar junction transistor. When VCC is connected to the collecter, everything works fine.
But if i connect GND to the collector the transistor doesn’t work:
- if the voltage is below 8V insted of the 18V the transistor heats up and draws tons of current without operating the motors
- if the voltage is 18V the motors always move, even if there is nothing connected to the base
Can someone tell me what i did wrong, or should i use just a different transistor?