I am trying to close the normally open (NO) mechanical relay contacts using the circuit below. . The mechanical relay is Panasonic Relay. I notice that when I give the high command for my GPIO I do see the LED turn-on and I hear a very soft click coming from the relay. Much quieter than I am used to but if I test the resistance across the NO relay contacts there is no connection. On the transistor I read approximately 0.78V on pin 1, 0V on pin2, and 0.026V on pin 3. I read 4.95V on A2 of the relay and 3.14V on the GPIO.
Does anyone know what may be the issue? Also is there any polarity in the A1 and A2 contacts? If so I have not considered this..
The transistor I used transistor datasheet