I have a GB Instruments GMT-19A. I want to measure current under 500ma. Scale selections are 500ma, 50ma, and 5ma. The scale readings include 250, 50, 10. What scale reading do I use to read the results for each ma scale selection? The instruction book that came with the meter are ambiguous and doesn't explain how to measure current under 500ma
Measuring Tools & Sensors - Gardner Bender - GB Electrical GMT-19A 19 Range Analog Multitester
You would use the 500ma range to read anything that is under 500 ma. If the reading comes up below 5o ma, then you can disconnect and change the range to 50 ma. I say disconnect before you change the range because it can damage the instrument otherwise. ie: do not use the switch to change the range while it is already connected in circuit and measuring in progress. Remember that to measure current, you have to have the meter in series with the load and the supply.
Answers & Comments
You would use the 500ma range to read anything that is under 500 ma. If the reading comes up below 5o ma, then you can disconnect and change the range to 50 ma. I say disconnect before you change the range because it can damage the instrument otherwise. ie: do not use the switch to change the range while it is already connected in circuit and measuring in progress.
Remember that to measure current, you have to have the meter in series with the load and the supply.