Appliances that are operated using an unstable power supply often end up getting burnt out. If you’re not getting a constant 240V power supply, it’s necessary to get it fixed before all your appliances end up needing replacement or repairs.
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The problem can be with the supply, breakers, wiring or simply anything else involved in the circuit. It may not always require a professional electrician for getting fixed though.
If you’re not getting 240 volts, the cause is likely to be a faulty circuit breaker, loose connections or dirty contacts. This will then cause the connection to not be established and stop the flow of electricity.
Understanding the source of the problem can help you decide if it can be repaired by yourself or whether it requires the help of a professional.
To help you understand the probable reasons behind not getting the required 240V for your appliances, I’ve written this article that details out most of the reasons along with a few possible ways of getting them fixed.
Why You’re Not Getting 240 Volts
The main reasons why you’re not getting 240 volts is due to loose connections, a bad circuit breaker or dirty contacts.
The electric circuit feeding your home appliances involves quite a few components. The reason behind the appliances not receiving 240V can lie in any of them.
Here is a list of the most likely reasons why you may not be getting 240V for your appliances.
· Loose Connections
When there is a loose connection in the appliance or the breaker circuit, the voltage may spike up. The voltage reading may differ at the outlet and neutral to ground connections. One spot may give a 0V reading while the other might continue to give a 120V reading.
A non-contact voltage tester allows you to check the power at terminals easily. The screws that connect the wires can indicate a loose connection as well.
· Bad Circuit Breaker
The main breaker can often give a different reading between the two legs. This can happen due to a corroded or a damaged bus bar inside the breaker. If the main breaker doesn’t deliver the rated 240V reading between the two legs, then it should be replaced immediately to avoid any severe damage to the appliances.
As the main breaker is live and is held by a screw inside the circuit, it’s advisable to seek the assistance of a professional for getting it replaced. The overall cost including the professional’s charges may go up to $300.
· Tripped Circuit Breaker
When multiple 240V loads are wired to a circuit breaker, it may get tripped due to the overload. To address this issue, you need to check the slots in which the circuit breakers are connected.
The wire connecting the breaker to the two legs of the supply should be connected properly to both the legs. If both the wires are connected to either one of the two legs, the circuit breaker trips causing a variance in the rated 240V output.
· Unclean Contacts
The bus bar contacts of the main breaker often get clogged with dust or other particles. Corrosion can also clog the contacts. This can lead to a loose connection, which in turn will make the circuit deliver a lower output.
Simply switching the main breaker on and off for at least ten-twelve times can help get the contacts cleaned and working as intended.
· Safety Tip
While handling the main breaker circuit, you can use a no-contact tester. These testers are relatively safe to use and indicate where power is available in the circuit.
Why am I Only Getting 120 Volts on My Neutral?
The electrical load in the house determines the actual voltage on the neutral. The ideal voltage across on the neutral is expected to be 120V. However, if the load is extracting more power, the voltage will suffer a dip, resulting in neutral not getting 120 volts.
If all the electrical loads are turned off, this voltage at neutral may even go over 120V.
Up to a certain range, variance is acceptable. Beyond that range, the lights will get dim and electronic appliances may restart or not turn on at all.
· Check the Connections
If the voltage difference at neutral is significant, then the problem is often with a loose or broken wire. As the neutral has connections to the entire circuit, checking it could be a little complicated.
You may replace the broken wires immediately if you find any. You need to check for the entire connections between the load and the supply unit.
· Load Test
As already explained, the load plays a key role in determining the voltage at neutral. If there is a problem with the voltage at neutral, you can try running a load test.
Try switching off all your appliances and then check for the voltage at neutral. Gradually increase the load and check for the voltage at each step.
When connecting an appliance, if the voltage spikes or dips severely, the problem could be with that appliance.
120V on Each Leg but No 240V
There can be quite a few reasons behind someone reading 120V on each of the two legs, but not 240V between the two legs. Here are three of the most probable reasons that might cause the variance.
· Backfeed Voltage
The circuit may often be having a complete outage due to some faulty connection or component, but the two legs can still show a 120V reading. This happens due to the load backfeeding a voltage to the supply unit.
· Use of Inappropriate Breaker
Using an inappropriate breaker may end up connecting both legs on the same bus. This, in turn, may rupture the entire circuit risking a blowout. For the supply to work as intended, the breakers used should be in sync with the panel.
· Damaged Leg
This voltage of 120V at the two legs can also be read when one of the two legs is damaged. In the case of a damaged leg, the two legs will show a 120V reading due to the other working leg. However, the expected 240V between the two legs will not be available.
240V Outlet Only Giving 120V
Often the line to line voltage recorded can be just 120V instead of the expected 240V. This can happen either because of a bad breaker, a missing neutral, or an open leg. In all of these three cases, the line to ground voltage may remain the same but the line to line voltage may get reduced.
Apart from the supply unit, the problem might lie with the load’s receptacles as well. In such a case, the wire at the receptacle may not match the wire inside the junction box.
Troubleshooting a 240V Outlet that’s Not Working
The 240V outlets usually have a combined earth leakage detector and circuit breaker. The only other thing that is to be included in troubleshooting is the lead and plug.
How to Troubleshoot a 240V Outlet
Step 1 – Check the Earth Leakage Safety Switch
The first thing to do here is to check the Earth Leakage Safety Switch which might have tripped due to an old connection. Turn it on and off a couple of times to ensure that this is not the reason.
Step 2 – Check the Lead and Plug
The outlet lead must be plugged into the control panel. If that is loose or unplugged, the 240V outlet will not work.
Step 3 – Check the Control Panel and Outlet Connection
At times, the leads can accidentally get unplugged at either end. Check if the lead is plugged in properly at both the control panel and outlet.
Why am I only getting 50 Volts?
You may receive a 50V reading for ground even if the circuit breaker is tripped. This might happen when the neutral and ground touch each other or there is a short to ground connection.
In either case, check for all ground connections and ensure the neutral is not touching the ground. The load may try to return the voltage through ground, leaving it energized. This backfeed energized ground gives the 50V.
Why am I Only Getting 150 Volts?
Why are you not getting 150 volts? A lost neutral or ground connection can result in not getting 150 volts of power.
A lost neutral may affect the entire load. If you’re getting 150V, it can be a serious issue putting the entire house at risk. The first thing to do in such a situation is to check the breaker panel by testing all outlets.
If it’s either a lost neutral or ground, unplug all electronic appliances and turn the main supply off. Call the power supply company to get the issue fixed at the earliest.
How to Test for Low Voltage on 240V Outlet
Testing of a 240V outlet can be done using a no-touch tester for added safety. The tester should be calibrated with the correct voltage setting.
On inserting the negative and positive terminals of the tester in the outlet, if the voltage is lower than 220V, then the load connected to this outlet may not function as intended.
Dryer not Getting 240 Volts
The receptacles or the bus bar connections might result in the dryer not getting 240V. Here are a few steps which can come in handy to identify and fix the issue.
Step 1 – Check the Load Receptacles
Before starting the test, ensure that the power is turned off. Check the terminals by removing the receptacles.
Step 2 – Test both Legs Individually
If there are no visible problems with the receptacles, go ahead and turn the power on. Test the voltage between each leg and ground.
If the voltage at one of the two legs is much lower than intended, then there is a bad connection. I recommend calling a professional electrician to fix this issue.
Step 3 – Check the Receptacle Cable
The cable at the receptacle should match with that of the panel. If there is a different cable at the two ends, then there can be a bad connection at the receptacles.
Don’t turn the dryer ON until the bad connection is spotted and fixed. Doing so could burn the dryer completely.
AC Not Getting 240 Volts
A 240V rated AC may operate properly when the supply voltage is below the rated voltage. At times the fan may continue to work at a slower speed when it’s not getting 240V. Apart from the fan, the indicator lights may also operate if the voltage received is below 240V.
When the neutral is missing, 120V is received by the AC. This 120V is what operates the fan and indicator lights as these don’t require a neutral essentially. Hence, in such a case, the problem is of a missing neutral wire.
If the AC is not operating at all, then the problem can be with the breaker or the supply line, which may not have 240V.
Here are a few tips that can be helpful to fix an AC not receiving 240V:
· Check the Wiring
As mentioned above, the problem may lie with a missing neutral. A complete check-up of the wiring is required to identify the problem.
· Check the Breaker Circuit
If your AC is receiving a supply below the rated supply without the main breaker getting tripped, there may be a chance that the main breaker has incorrect connections. The poles should be connected to the main breaker panel in the desired manner. Any changes can deviate the voltage received by the AC.
· Check the Supply Line
This is a rarity, but it is still a possibility. At times, the supply line may not be 240V. Trying to operate a 240V rated AC on such a line will give a voltage below the 240V mark. In such a case, the 240V AC cannot be operated.