Although i have now spent a considerable amount of time studying electronics at a hobby level I am still stumped by the concept of earth ground.
My question is, should there be a potential difference between a positive battery terminal and earth ground?
After searching the internet for an answer to no avail i set fourth into my backyard carrying a metal dog stake (to use as my ground stake) a multimeter, a 6 V battery and an alligator clip connector to a banana plug lead. I then performed the following experiment:
1) I tested that the stake would conduct current by performing a continuity test with my DMM (this revealed that the resistance of the stake was only a few ohms).
2) I tested the battery pack worked by hooking it up to my breadboard and powering up a circuit I had previously built.
3) I connected one end of the alligator clip to the dog stake and the other end to the negative terminal of my multimeter.
4) I connected the positive battery terminal to the positive terminal of my multimeter.
5) I set my autoranging multimeter to volts. At this point i expected to see a potential difference between positive battery terminal and ground (such as 3V for instance). The potential difference seemed to fluctuate between 0 to 100mV however. This is not what i expected. Is my fundamental understanding of earth ground incorrect?
I also tried a similar experiment using my kitchen sink instead of the dog stake. Again, there was no appreciable potential difference. I also tried using my multimeter as an ammeter and saw that there was no current between the positive terminal and the kitchen sink. Just for shits and giggles I even tried the negative battery terminal and still nothing.
My understanding of ground is that it is like a 0V battery terminal. Is this not the case?
If the problem is in my method of testing the ground connection, then what is the correct method to use?
My question is, should there be a potential difference between a positive battery terminal and earth ground?
After searching the internet for an answer to no avail i set fourth into my backyard carrying a metal dog stake (to use as my ground stake) a multimeter, a 6 V battery and an alligator clip connector to a banana plug lead. I then performed the following experiment:
1) I tested that the stake would conduct current by performing a continuity test with my DMM (this revealed that the resistance of the stake was only a few ohms).
2) I tested the battery pack worked by hooking it up to my breadboard and powering up a circuit I had previously built.
3) I connected one end of the alligator clip to the dog stake and the other end to the negative terminal of my multimeter.
4) I connected the positive battery terminal to the positive terminal of my multimeter.
5) I set my autoranging multimeter to volts. At this point i expected to see a potential difference between positive battery terminal and ground (such as 3V for instance). The potential difference seemed to fluctuate between 0 to 100mV however. This is not what i expected. Is my fundamental understanding of earth ground incorrect?
I also tried a similar experiment using my kitchen sink instead of the dog stake. Again, there was no appreciable potential difference. I also tried using my multimeter as an ammeter and saw that there was no current between the positive terminal and the kitchen sink. Just for shits and giggles I even tried the negative battery terminal and still nothing.
My understanding of ground is that it is like a 0V battery terminal. Is this not the case?
If the problem is in my method of testing the ground connection, then what is the correct method to use?