Most compressor motors will run on 120 volts or 240 volts. And need someone to simplify this for me. [This message has been edited by electure (edited 11-20-2006).] Is there a way to do that successfully without a step up transformer? With this arrangement the single phase voltage from ground and/or neutral to "B" phase is 208 volts … That's the one you need to disconnect and connect to C. And the winding end at A needs to be brought to B. The motors that are truly intended for 208 volts are nameplated for 200 volts. A typical AC induction motor well pump will need around 3-5 times is rated wattage for an inverter to start it. The big brother of that system is the ungrounded 3-phase, 3-wire 480-volt system. If you are using the converter for a large appliance like a refrigerator or washer, buy a heavy duty one that can handle the large loads and constant use. Experience: 10 yrs as a electrician. It is possible to use a power inverter to change your cars DC output to AC power for your sump pump to utilize. If you don't have a wiring diagram, and the motor is currently wired for 240 volts, you can identify point "B" by the fact that it isn't connected to either power lead. If so how would I do that. why did the uk change to say they run a 230 volt/50hz +10%/-6% system when in actual fact they still supply at 240 volts. Most motors that are rated at 230 volts will run on 208 volt power, although this is not recommended. It may only involve switching a few wires inside the motor and replacing the plug.Then consult a licensed electrician about adding a 240-volt … 12.5 x 1.25 = 16 amps so I could use 12/2 g on a 20 amp breaker. Three phase voltages generally available are 208 volt, 240 volt, 480 volt and 600 volt. #72152 11/20/06 09:07 PM: Joined: Jan 2005. 220v and 110v systems are compatible, they just need a voltage converter. Two: the cable might notfit the appropriately-sized breaker on a long run. Roy is correct, you can run a AC/DC Welder on 208, but the amperage setting will have to be set higher than it would be at 240 volts. 230 volt motors are designed to run on 240. Every 440 v motor I have seen is 3 phase, so I would assume yours is too. 3 Phase Motor Voltages: 208 vs. 240 #130240 02/24/06 08:30 AM: Joined: Feb 2006. For this reason, you should crimp wire lugs onto the ends of the wires before connecting them to the receptacle. But it hasn't been that way for some 50 years now. My … The horsepower will be lowered by .9 or to 90% of the nameplate rating. To get the best performance from a direct current (DC) motor it is advised to use the same voltage power supply as the input voltage of the motor. Adding a 240 outlet to your house will require an electrician. We have not hooked it up yet. What is the relationship between the two. If the service was a pure 208 volts, at a minimum, then the motor would work. I have already wired it using the motor common as a neutral and the hot leg to the High speed leg and it spins but slowly. Kind Regards, John. So you can't have a car battery sump pump backup without an inverter. I have retrieved a blower motor out of an old air handler. You need a 240 volt primary by 208Y/120 secondary transformer. Re: Can a 240 Volt motor be run from 120 Volt power? The main consideration during the conversion is the ampacity of the wires, which must conform to the National Electric Code Wire Ampacity Table 310-16 for the amount of current they will carry. If you can't get a 208 rated motor (or one which has multiple voltage ratings like 208-230, which are made) -- then you're better off looking to insert transformation to get back up to 230 volts; this could be a 2-winding transformer of 208-230 volts or else you could get three (3) buck-boost transformers (2 winding units configured as auto-transformers) to get you there. You'll be using this in step-up configuration, so do not hook up the neutral wire. e.g. Re: changing a dedicated 460 volt motor to a 230 volt motor 05/12/2009 4:39 PM jmueller; if there are 6 leads brought out of the motor it can be connected star or delta as an example 220 volt 3 phase delta, or 380 volt 3 phase star(wye) , or 240/415 volt or 230 volt/400 volt. The wire is 10-gauge or thicker, which makes it hard to bend. This can cause twoproblems. You can buy a step up transformer to go from 220v to 440V and these can be found at electrical supply houses or surplus. The 240 volt outlets have 1 vertical and one horizontal slot. They both have 120 volt electric motors. Strange, but true. This ensures secure connections. Show Less . My motor, pool pump, has 2 hot wires and a bare wire as a ground. S. skipr. Most AC motors are built to tolerate a 10% variation from nameplate voltage. If you plug an 110V appliance in 220V outlet (same as 120v to 230v, 240v) you can only hope that some protection device disconnects the power to the appliance. Yes, a 230 volt electric motor can run on 208 volts. 120 volts is generally used on motors no larger than 1/3 horsepower. Also neutral to ground. Neutral should be within millivolts of ground. You can usually get your basic sheathed xx/2 and xx/3cable up to 6 guage. Yes, you can wire a 240-volt rated water heater with 120-volts, exchanging the second hot (red) wire for a white (neutral) wire to the neutral bus. Actually, the nominal voltage is 120/240V for U.S. residential outlets nowadays. North Carolina. Any opinions on running 3 phase motors rated at 220/230/240 volts on 208 volts? Rick, Master Electrician. First answer: NO, YOU CAN"T RUN A 230 or 240 Volt motor on 277 Volts or 480 Volts. The cable you need for 230-volt wiring includes two hot wires, a neutral and a ground. Satisfied Customers: 467. And; 230 Volts is the standard motor voltage in north America. I am doing a resturant where the customer is being told that they need to buy a $700 transformer to make a 200 volt three phase motor run correctly. I'm now able to use this design by choosing 240 volt heaters. perry Using an ohm meter, check which of the three wires from B lead to the power lead with just one wire attached to it. R. rhpope OP. So 120 volts is not an option. Category: Electrical. If it's 460V star on the Nema motor plate, just bridge the motor terminals in parallel/Delta and it will run on 220V 3phase. No problemo so long as your service line voltage runs between 209 and 253 volts your 230 volt NEMA compliant motor should run just fine. Ask Your Own Electrical Question. When a motor is rated at 208/230 volts this means the motor will operate at the 208 volt rating, not 10% under the 208 volt rating. Most sump pumps operate on a standard 110-volt AC outlet. A 230 volt 10 HP motor will only produce 9 HP at 208 volts. I would like to have it operate on 120 volt if possible. "Generally available power supply voltages for single phase are 120 volt and 240 volt. So, a 230 volt motor can operate as low as 207 volts. the motor is specked to run on 208/230. This motor would allow the minimum voltage to be 180 volts. How far can I run 240 volts single phase for 100 amps, what wire size is needed, what is price of wire. Then, take out the old 120 volt receptacle, and install a 240/230 volt receptacle that fits the plug on your fridge. If you have more than one machine that is rated at 230, consider installing a larger dedicated transformer and panel board to run those machines at 240 delta. 30 amp breaker is fine 240 volt heater on 208 will just be a little slower .If this is a home I would not be concerned. Share this conversation. And I believe this is to tolerate some voltage drop in the line. I have seen this done before without any problems, but I am looking for opinions on the extra current draw and possibility of overheating by running at the lower voltage. 460 volt motors are designed to run on 480 208/230 volt motors are designed for use with 208 or 240 volt supplies. « Reply #21 on: January 17, 2013, 05:06:54 pm » If there's no 240V supply available, you could use … So you are essentially using the same "homerun" wire, just switching the connections at each end. Because of Ohm’s Law and the fact that the resistance of the circuit stays the same, half the voltage means the watts of heating energy generated is reduced to one quarter of what it was at 240 volts. A 110 volt wall outlet has 2 slots running vertically. Otherwise: If it is some kind of heating device, (toaster, incandescent light, lamp, bulb, space heater) it will develop close to four times the designed heat, and probably burn out in minutes, or seconds. I am sending you an image with instructions of how to change a motor over from 240 to 120 volts. Electrician: Rick, Master Electrician replied 8 years ago. A 30 KVA transformer will give you 72 amps at 240. A standard 110- to 125-volt outlet converts easily to a 220- to 250-volt outlet. Most of the transformers you see are huge monsters, which would probably be too much. 5 Responses to “Converting a 120 Volt Motor to 240 Volts” John Healey says: January 15, 2015 at 5:53 pm. I look forward to hearing from you. I'm trying to run one hot water circulator, 120 volt, with 2 switches, one a 60 minute timer, and the other is one leg of the 220 relay.If I want to heat the pool I turn on the timer for an hour a day. Re: 208/230v can run off 240? Lower voltage /higher current will work just fine. A lot of appliances will say 115V or 230. Posts: 18. Convert 110-volt outlets to 240 volts for 240-volt appliances. Can these motors be changed to 240 volts as I live in New Zealand where our country is 240 volts. Be sure to clearly label the wires as 240 volts on each end for safety. Looking at 240 volt heaters I will have 3000/240 = 12.5 amps. So Im a little confused with the whole 230/240 volt situation. Member. Have a certified electrician do this work for you. I bought 2 ALECO DRYWALL SANDERS from a source online. 110 or 220 is still used colloquially. But; Most 230 Volt 3 phase motors are dual voltage and will run on either 240 Volts or 480 Volts. It may help to draw a vector sketch. Say your pump needs 1,000 watts to run, you will probably need a 2,000 watt or larger inverter to run it (it also depends on the inverters--some are much better at supporting surge loads than others). If your motor exceeds this guideline, and popping your breaker is still a problem, your best bet is to rewire the motor to 240 volts. If you need larger than #8 or #6 though, you willhave to buy service or "service type" cable. This arrangement allows us to service 120:240 Volt single phase loads and 240 Volt three phase loads from the same transformer bank and the same panel. Right now we have 208. One: very high cost on long runs. By the way check your incoming line voltage across the line and from line to neutral. Since there is a voltage drop between the power source and the electric motor, the single phase motors are rated either 115 volt or 230 volt. Log in to Reply. Member. Posts: 39. The line to neutral should be very close to 1/2 of line volts. Unground- ... volts), and you were using a 230-volt motor, then the 230-volt motor could only go down to 207 volts (–10%) without being in trouble. Huntington Beach, Ca. Show More. I know alot of single phase motors are labled 230 volts and we put them on 240 … Beware of the quality of motors rated at 240 Volts. Answered in 1 minute by: 7/3/2012. is 240 volts. electric water heater. The range for a 230 volt motor is 207 to 253 volts. 120 volts, the second at 240 volts.)