ThE_sPaCeCoWbOy
New Member
I hook up a 2n2700 up to a 9-18VDC motor that can handle 1.98A.
I limited the amps to 200mA and set the Vd = 9V, put a 2.7ohm resistor in series iwth the motor. Turned the transistor on, and it works, but the actual numbers i'm measuring (V, A, R) are not what I calculated and its not the tolerance difference either.
Vd=9
Vmotor = 8 V
Rmotor = 2.4
R = 2.4
I should get Id=208mA
Now when I measure, I get Vmotor = 7.3, Id = 270mA. This is telling me that I have 6.3 ohms of resistance and my meter is telling that this is not what I have. Any clues where this added resistance might be coming from or if i'm doing something wrong?
Thanks,
space
I limited the amps to 200mA and set the Vd = 9V, put a 2.7ohm resistor in series iwth the motor. Turned the transistor on, and it works, but the actual numbers i'm measuring (V, A, R) are not what I calculated and its not the tolerance difference either.
Vd=9
Vmotor = 8 V
Rmotor = 2.4
R = 2.4
I should get Id=208mA
Now when I measure, I get Vmotor = 7.3, Id = 270mA. This is telling me that I have 6.3 ohms of resistance and my meter is telling that this is not what I have. Any clues where this added resistance might be coming from or if i'm doing something wrong?
Thanks,
space