DC Motor Control

468

06:12:11

My controller is using two12V relays to switch the needed current to the motor(forward and backward) . I added a second motor with its own two relays, but the current was not enough to drive the additional relays. 

Switching is done with a Single 12v line and two switched ground lines which are pulled low to switch the relay. 

Therefor I am using transistors and the 12V from the battery to amplify the current to the additional relays 

Comments are appreciated.

published 7 years ago

BillyT

7 years ago

Transistors are reverse wired and connected. Simplify the circuit, you only need one power supply.

Spunkmeyer

7 years ago

Thanks Billy. There Power for the transistors is ttl logic from another Board. two switched grounds and a Single 12v line. the current is insufficient, therefor the second supply. whats the difference between Wired and connected?

Spunkmeyer

7 years ago

I flipped the transistors and it still works.

BillyT

7 years ago

If you are using dual transistors to drive the relays I would normally use the first transistor as a Voltage amplifier to drive the next as a current amplifier to drive the relay.

Spunkmeyer

7 years ago

Thanks a lot. Since there is already 12V I simplyfied the circuit. I also changed the description to tell the situation in which I use this.

BillyT

7 years ago

Check out this circuit; http://everycircuit.com/circuit/5990016244514816

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