29
votes
Is it possible to dangerously short a U.S. power outlet with multimeter probe?
Unless you shattered the insides of a normal outlet, you wouldn't be able to short out the outlet using a multi-meter.
Looking at the picture below,
each female part of the socket is in its own ...
- 72k
28
votes
Accepted
Analog multimeter won't calibrate to zero
I assume, since it has a zero-ohms adjustment at all, that this is an analog multimeter (one with a physical moving needle). In which case, you should try replacing the internal batteries. They are ...
- 3,583
21
votes
Which terminal to use on my multimeter
Stay away from the 10A terminal. That is for amp measurements ONLY, and creates a dead short between the 10A terminal and the common. This will blow your fuse, burn up your probes, and/or destroy ...
21
votes
Accepted
Diagnosing appliance that shocked me
Thanks to everyone and particularly to ThreePhaseEel for his suggestion that helped me diagnose the issue.
My non-contact voltage detector picks up current within about 18 inches of the fan housing, ...
- 1,417
19
votes
Is it possible to dangerously short a U.S. power outlet with multimeter probe?
Don't handle the probes carelessly. Given that the probe metal contact has some length, it's possible to bridge them across two contacts or cross them (although this would be fantastically difficult ...
12
votes
Which terminal to use on my multimeter
Keep in mind that using a meter that's not rated for the task can be dangerous! Even with relatively low risk things like residential receptacles.
Right off the bat - if you got this meter for ...
- 24.7k
12
votes
Is it possible to dangerously short a U.S. power outlet with multimeter probe?
It is possible in any given outlet that behind the contact for one prong there is an uninsulated metal component leading to a different prong. But to short circuit the two together with a probe would ...
- 28.4k
12
votes
Accepted
How do I test for voltage drop?
it seems like it's only dropping under load
Yes, that’s how voltage drop works. Ohm’s Law is V=I*R. If no current is flowing through a high resistance (such as a bad connection or excessively long, ...
- 4,820
9
votes
Accepted
Clamp DC current measurements with AmazonCommercial 600A AC/DC Clamp Meter
You're not using it correctly.
You can only have a single wire running though the clamp - in all the cases you show here you have 2 wires - even the 1st pics with the adapter plugged in to the outlet ...
- 5,516
9
votes
One hot leg to neutral of 4-prong dryer reading 240 volts and other hot leg to neutral reading 0 volts
Based on the picture and description, the only thing that makes sense is a short between white (neutral) and black (hot 1). There are a few different possible places for the problem:
Receptacle
Plug
...
8
votes
Accepted
Can I use a multi-function "clamp" meter to measure resistance?
The "clamp" portion of the clamp meter is just for additional functionality vs. a traditional multimeter. The clamp is for measuring current and frequency only. All other functions are ...
- 6,074
8
votes
How do I test for voltage drop?
Voltage drop can be several things.
First, it can simply be the length of the circuit. You are reporting 12 volts of voltage drop (10%). If the circuit is wired with 12 AWG wire and is 290 feet from ...
7
votes
How to replace bearings on a multimeter knob?
The best way to repair it is to replace it. They are not super expensive and a new one will remain accurate for a long time. Repairing this without experience will probably yield an unstable meter. ...
- 5,874
6
votes
Troubleshooting Clamp Meter
Imagine a single, solitary wire. When AC current goes through it, it kicks up a significant Electro-Magnetic Field (EMF). If that field interacts with anything metallic, it can cause all sorts of ...
6
votes
Accepted
Troubleshooting Clamp Meter
You say that you put the clamp around a live lamp cord, but for a clamp meter to work, you have to put the clamp around only ONE of the conductors. If you clamp around both wires, you will not get a ...
- 27.1k
6
votes
Accepted
What happens if I use the DC Voltage setting on an AC line? What about the reverse?
As long as the meter's voltage range is initially set to at least the highest that can be there, you won't damage the meter, especially if you make just a momentary initial connection to see what the ...
- 5,988
6
votes
Is it possible to dangerously short a U.S. power outlet with multimeter probe?
Use a multimeter designed for what you're using it for!
Your multimeter has a category rating, from I to IV, and a voltage area. This tells you something about what kind of systems it's intended to be ...
- 1,505
5
votes
Accepted
DIY AC Line Splitter
I have created a line splitter like this with a heavy duty male and female three prong plug and three 14g wires - white, black, and green. 12/2 romex will have a bare copper ground, and I didn't want ...
- 27.1k
5
votes
Tried repairing a broken lamp and it's weirdly dim - high resistance in wire?
Likely is a bad switch, or a bad connection.
Unlikely is "high resistance wire"
And if you are planning to "put your engineering degree to use" please learn the difference in line ...
- 174k
5
votes
Unable to measure table lamp AC amps using clamp meter
The major sellers of Mastech meters are Amazon, eBay, AliExpress, Konga, Joom, Indiamart and wish.com. That is a huge red flag for cheap counterfeit crud, right off the boat.
If that fact did not ...
4
votes
Which terminal to use on my multimeter
Memory key: Because you want to measure voltage (V), use the VΩmA terminal.
(Also use that terminal for measuring resistance (Ω) and small currents (mA).)
The 10A terminal is special purpose, only ...
- 41
4
votes
How to test voltage on open wire with multimeter?
Two suggestions:
A non-contact voltage tester can detect line-level voltage without needing to complete a circuit. It does this by detecting the alternating electric field that radiates off any “live”...
- 306
4
votes
Diagnosing appliance that shocked me
If the outlet safety ground is not really grounded, but is open or perhaps connected to neutral, this could explain what you described. Check the outlet ground to water pipe resistance. This should ...
- 151
4
votes
Unable to measure table lamp AC amps using clamp meter
What does "AC Current:60A/600A/1000A" mean?
That means the meter can measure three ranges and report them on its four-digit display:
00.00A - 60.00A (0.01A resolution)
000.0A - 600.0A (0....
- 4,820
4
votes
Can a multimeter be used to detect if an appliance's body has voltage on it?
If the light fitting requires an earth / ground connection then it would be foolish to use it without the earth / ground connection. The earth connection is designed to prevent the metallic parts ...
- 864
4
votes
Can a multimeter be used to detect if an appliance's body has voltage on it?
Set "AC 600 V" range. Connect the one (black) voltmeter's probe to the nearest earth wire (green and yellow); you may need to use an extension wire. Where to find it depends on the AC system ...
4
votes
Is it possible to dangerously short a U.S. power outlet with multimeter probe?
If you are a European reading answers to this US-oriented question, the following applies. If you are one of the other 90% of people who live elsewhere, it may or may not.
These are made for the ...
- 24k
4
votes
One hot leg to neutral of 4-prong dryer reading 240 volts and other hot leg to neutral reading 0 volts
Sounds like a Lost Neutral to me.
I think the neutral wire in your wall is broken or disconnected, either inside the junction box, or inside the service panel.
Checking voltage at the socket would ...
4
votes
Can I use a multi-function "clamp" meter to measure resistance?
Your clamp meter is just an electrical multitool. The jaws are for measuring AC current only, although I think one tip also has a non-contact voltage detector.
Just use the normal test probes and the ...
- 3,814
3
votes
Accepted
Can I check the wattage / amps of a pair of light fixtures using a multimeter
It sounds as if you want to measure wattage/amps of mains-powered lamps, which are probably powered from an AC source. Unfortunately the meter you mentioned cannot measure AC current; it does DC only.
...
- 24.3k
Only top scored, non community-wiki answers of a minimum length are eligible