How to Check 240 Voltage With a Multimeter?

If you’re an electrician aspirant, then this blog post is for you. In this blog post, we will be looking at the steps involved in checking 240 volts with a multimeter.

First off, we need to set our multimeter to read AC voltage or current, and it should be set on the highest range possible (usually 200 volts). The next step would be connecting one probe of your multimeter to the hot wire and the other probe to the neutral wire linked from the breaker panel. 

Now, if there is an increase in reading, that means that electricity has been flowing through wires, which means there’s a power outage, but if there isn’t any change in readings, it means that the circuit breaker is tripped or a fuse blown.

Checking 240 volts Using a Multimeter

A multimeter is an excellent tool for checking the voltage of an electrical circuit. To do this, you will need to adjust your dial or setting so that it reads 120 volts AC and then insert one probe into any socket on the slanted side and slip another probe’s metal tip in a middle slot. 

If there are no adjacent slots labeled with 110-volt labels next to where you inserted probes, what does this mean? It means that circuit isn’t working!

Steps for running a test on your 220v outlet using a multimeter.

  1. When you’re about to test a live outlet, you must exercise safety measures. Hold your multimeter probes in one hand and make sure they don’t touch each other, or the metal part of them will cause an unsafe short circuit.
  2. What’s the deal with outlets? There are three slots. One is neutral, one is hot, and finally, there will be a ground slot for grounding your wire. The ground has an extended horizontal cutout on its left side while the other two have shorter ones on their right sides – that should make it easy to figure out which wires go where!
  3. The 220v outlet is usually found in the utility room, which its label can identify. You should see your circuit breaker to ensure that you are using a two-pole breaker for this particular installation and not any other breakers that may cause trouble with another appliance like it.
  4. To measure voltage, switch on the energy of your multimeter and set it to AC. Next, turn the selector knob at the front side of your meter and choose a symbol set that matches the outlet’s current – ideally between 220-240 VAC (usually denoted by an alternating line in the waveform). When you’re done selecting this, remember to click back over onto DC, where there will be both dashed and solid lines representing direct currents instead.
  5. You’ll need to plug in your two tester leads into the multimeter. The negative blackjack, which has a minus sign and is colored black, should have its lead inserted into it, while the positive red jack with a plus sign and is colored red will require that you insert its lead.
  6. Plug two of your test leads into the outlet. If you have a three-pronged outlet, one or both slots will be slanted, and for those with 4 prongs, there are 2 outside vertical slots on each side as well. Once plugged in, make sure to check that the voltage reading is between 220-240 volts before proceeding any further!
  7. Plug the black test lead into a neutral slot, and you redone it into hot. This also applies for 3, 4 prolong outlets; neutrality is usually L-shaped. As such, read what’s being displayed: it needs to be between 110 – 120 volts. After that, put down the red probe on its outlet with no connection (hot), then insert another black test lead back onto where you originally pulled away from(neutral). The reading value shown must be around those same values of 110-120V. After this, remove both probes from their sockets and switch off your multimeter!
  8. After the dryer is hooked up to a 220V outlet, it’s safe for you to plug in your cord. If the readings don’t match what we’re looking for, please do not proceed with connecting. There will be an increased risk of electrocution and potential injury resulting from improper wiring or installation of this appliance.

Testing a 240-Volt Circuit

  1. The outlet on your wall is 240-volt. It has three openings: two identical slots slanted at 45 degrees (sometimes vertical) and one middle slot lower than the two vertical ones. The 120 volts come from each of these, while you can ground yourself in the third or middle slot that’s not as high up like they are!
  2. With the voltage dial set to 240 volts AC, connect your black probe to one of the terminals and your red probe on an empty terminal. Never touch both metal tips when in use or risk getting a massive shock!
  3. Slip the metal end of one test probe into any slanted 120-volt slots and slip the other test probe’s metal end into an adjacent slot. Look at your multimeter reading, which should be approximately 240 volts if all is functioning correctly. If it isn’t displaying a voltage that matches this number, check out what might not be working with either circuit before continuing to work on them individually.”
  4. Find the multimeter’s dial. Set it to 120 volts AC. Insert one of your probes into any slanted, red slot and another probe in any black slot at the end opposite from where you inserted the first probe. If both circuits are working correctly, then reading should appear on your screen indicating approximately 120vac; if not, switch slots until you get a reading that indicates proper voltage operation.

Testing a 240-Volt Receptacles

  1. To test the outlet, you will need to first unplug your appliance from it to no current running through it. You may find this challenging and time-consuming, but be careful not to damage any appliance parts for them to work correctly again.
  2. Turn on and set the function switch to “AC Volt.” If you have an auto-ranging meter, it will select which range is appropriate for testing this number. For manual meters that don’t automatically adjust their ranges based on what voltages are being tested, change over to 500 volts AC by setting Function/Range Switch to position “500 Volts AC.”
  3. Place one of the test probes in each vertical slot on your receptacle’s left and right sides. If both hot wires have voltage, you’ll see a reading between 220-240 volts displayed on the LCD; if not, go to the next step.
  4. The reading on the voltmeter should be something like 110 to 120 when measuring each phase-wire slot and system ground. The problem is an open phase if there’s no voltage in one of these measurements but not with all other readings taken from another wire or grounding point. If this turns out to be your case, you can proceed by following the following steps:
  5. Did you know that most homes still use fuses instead of circuit breakers, and one fuse can blow while the other remains viable? If a faulty wire or receptacle is not your problem, there may have been an open phase reading. Resetting the breaker by switching it off and back on might fix this issue if only one pole tripped closed when another remained open.
  6. Take a reading between each phase wire slot and the neutral wire slot at the top of your receptacle. The meter should display 110 to 120 volts between each of them, but if you have 220 to 240 volts, then it means that there is an extra line in operation which goes back through another outlet or light switch on its way out – this will cause power outage problems.

There are many different ways to test a 220v outlet, but we want you to have the best possible experience in this article. 

We hope that reading through these steps has given you all the information necessary, and now your next step is just making sure not only do they match up with what’s on your script or manual but also make sure any readings are accurate for safe use of equipment.

About Blake Sutton

Blake has worked as an electrician for over 10 years, receiving his Journeyman Electrician license in 1998. Looking to take his professional electrical career further, in 2008 he received his Bachelor of Science in Electrical Engineering (BSEE) from the University of Texas in Austin. Blake now works full time as an electrical engineer, specializing in power systems.