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Volt meter analog11/23/2023 ![]() Unplug all of the cords from the outlet and plug in one cord to test if it’s working. A refrigerator capacitor most often refers to the more common run capacitor in a fridge. In this HVAC Service Training Video, I explain Step By Step How to Troubleshoot a Refrigerator Compressor that will not Start. When it stops working, your refrigerator won’t cool. If you like my video please don't fo Remove either of the wires from a terminal on the capacitor. How to test a refrigerator capacitor with a multimeter.Exercise the needle a few times with power or the toothpick. If nothing has worked, try putting one drop of 99% isopropyl alcohol on each pivot. Use any convenient resistor and power supply to accomplish this. So, if you connect your cliplead to the point between the internal resistor and the meter movement, it will take 1 ma of current to get a full scale reading. But don't use 300V! You measured 301K resistance which means that the meter is 1 ma full scale. You can either move the pointer with a toothpick or something similar (so you don't scratch the scale) or ideally, by using power. Is the pointer bent? Is the scale bent? Does the pointer look like it might be touching the scale? Is the pointer bent away from the scale so it might be touching the inside of the cover? If your inspection doesn't show anything obvious, confirm that it still sticks when it's outside the case. ![]() Now do a good visual inspection under strong light. The entire unit should lift out of the case. Remove it from the panel and then remove the movement from the plastic case by removing all the nuts and bolts on the back. I'd take another look at repairing the meter. It might be easier to swap both meters so they match. In a case like this where you've got two that are supposed to match, it can get downright ugly. Swapping out a non-standard analog meter like this one can be a nuisance. Some people change the numbers on a meter and change the internal resistor(s) as necessary. I can see screws holding the scale in place, but similar-looking Modutec meters don't have visible screws. Your meter looks like it's Modutec, but it says Beede on the back. If the new meter is a different brand, it gets much more complicated. It may or may not be possible to move the scale. There's another one but it costs about $50 and still might be too big. I saw this one:, but it looks like it's too big. There's too much 'stuff' inside that you have to remove. ![]() No, don't buy that meter! Don't buy an AC meter. Move very carefully! An analog meter is a very, very delicate device! Before touching it, see if you can find a web page or forum post on analog meter cleaning / repair. If the sticking is minor, the meter might just need cleaning. If the meter is sticking, then that's a completely different project! You could consider replacing the meter with another analog meter or a digital meter. But whatever is inside the meter, those internal resistor(s) could have drifted over the years. Maybe in this case, there's a voltage divider to ensure that the meter movement doesn't see a high voltage under any circumstances. Normally, a meter just has a resistor in series to set the maximum voltage reading. I'm used to nice, even numbers like 100 ua, 500 ua, 1 ma full scale for an analog meter. However, 2700 V and 7M65 gives a current of 352 ua full scale. ![]() ![]() That works out to 2K833 ohms/volt, not 1K ohms/volt. The resistors are supposed to be 3 X 2M55 = 7M65. That means the external resistors have to drop 2700 Vdc. I don't think I'd like to stick a screwdriver into a pot that was sitting hundreds of volts or more above ground! Either my calculator is broken or there's something odd here. I'd be cautious about using a potentiometer. As TheMG says, if the meter is mechanically sound, just adjust resistors as necessary to get the proper voltage reading. ![]()
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