CCCI
Member
- Location
- Orlando, Florida
I need to hook up a 220 volt motor to 208 volts. I believe that this would be fine because it is in the 10% area of the voltage. I'm I looking at this right?This is for a 1 1/2 HP drill press.
220V MOTOR on 208V
- Thread starter CCCI
- Start date
- Status
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
Do you really have a 220V motor, or is it listed as 230V on the nameplate?
As I have said in the past, the industry accepted -10% tolerance of an equipment's nameplate rating should never be used to justify installing it on a lower nominal voltage system.
Remember that the utility is usually allowed to deliver voltage 5% below nominal. This means that a 208V service can really be as low as 197.6V. So assuming that the low utility voltage is equal to the -10% tolerance of equipment, means a motor's nameplate needs to read 219.56V.
As I have said in the past, the industry accepted -10% tolerance of an equipment's nameplate rating should never be used to justify installing it on a lower nominal voltage system.
Remember that the utility is usually allowed to deliver voltage 5% below nominal. This means that a 208V service can really be as low as 197.6V. So assuming that the low utility voltage is equal to the -10% tolerance of equipment, means a motor's nameplate needs to read 219.56V.
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
Agreed with Jim: check the motor plate. It may very well be listed as 120/208-240.
CCCI
Member
- Location
- Orlando, Florida
Nameplate 110/220 Volts
Nameplate 110/220 Volts
The nameplate has 110/220V and the motor has a big sticker that says, "Pre wired 220 volts"
It also has a wiring diagram that has the 220v wiring in the owners manual and an NEMA 6-15 plug on the cord.
Nameplate 110/220 Volts
The nameplate has 110/220V and the motor has a big sticker that says, "Pre wired 220 volts"
It also has a wiring diagram that has the 220v wiring in the owners manual and an NEMA 6-15 plug on the cord.
Pierre C Belarge
Senior Member
- Location
- Westchester County, New York
This drill is not a large piece of equipment, I think you should be just fine...except maybe during "brownouts".
mdshunk
Senior Member
- Location
- Right here.
I often see 208 hovering closer to 215 anyhow. Many air conditioning compressors now say 200-230 volts on the dataplate.
e57
Senior Member
- Location
- San Francisco, CA
What system delivers 220 anyway?
kbsparky
Senior Member
- Location
- Delmarva, USA
European systems' nominal voltage can be 220/380 Volts.
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
CCCI said:
How old is this piece of equipment?
The standard US voltages for motors have been 115, 200, 230, 460, and 575V for over 40 years. Some motors may be listed with nominal supply voltages instead which are: 120, 208, 240, 480, and 600V.
e57
Senior Member
- Location
- San Francisco, CA
Buddy, I was trying to do the lead in for "220... 221 ~ whatever it takes.":wink:kbsparky said:
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
Mr. Mom.e57 said:
e57
Senior Member
- Location
- San Francisco, CA
A ruttin tutin' Larry.
CCCI
Member
- Location
- Orlando, Florida
Taiwan
Taiwan
I just found out that it was made in Taiwan that has a 110/220 volt system. We have 209.5 volts at the location that it will be hooked up at.
Taiwan
I just found out that it was made in Taiwan that has a 110/220 volt system. We have 209.5 volts at the location that it will be hooked up at.
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
CCCI said:
What you have today does not directly relate to what you will have tomorrow, that is why +/- tolerances are associated with nominal voltages. Any time they want to, your utility can go down to 198V. And is there proof that your 220V equipment actually has a -10% tolerance?
If the equipment is expensive and you don't like being on the extreme edge, you could always get a buck/boost transformer.
Check to see what a replacement motor would cost. Then run the one you have, if it burns up you've got a heads up to get a quick replacement. What else can you do. Something is going to cost money either way. My only question is there any other equipment that will run into issues with the 208 volts. If so then it would be worth looking into other options.
quogueelectric
Senior Member
- Location
- new york
combination starter
combination starter
Install a combination starter with a heater section as a disconnect drop a recepticle out where you need to plug in and set the heaters very tight to fla to protect the windings
combination starter
Install a combination starter with a heater section as a disconnect drop a recepticle out where you need to plug in and set the heaters very tight to fla to protect the windings
GeorgeB
ElectroHydraulics engineer (retired)
- Location
- Greenville SC
- Occupation
- Retired
Motor terminal voltage with panel of 234, 200 ft of #14, 10A load, plug and cord connected ... very realistic. If you look on Baldor's website, they have single phase motors rated at 110/220, 115/230, and 115/208-230. I find the voltage selections interesting with 208 being sqrt(3) related to 120, not 115 ...e57 said:
Ah well.
- Location
- Wisconsin
- Occupation
- PE (Retired) - Power Systems
GeorgeB said:
115V is 1/2 of 230V. Standard motor windings are connected in parallel for 115V or series for 230V, this is what makes getting 200(208)V ones difficult. A 230V motor is designed an intended to be installed on a 240V supply.
If you use the assumed +/-% tolerance of the motor's nameplate than you run the risk of having problems when the utility decides to use their allowable +/-% of nominal. A 240V supply is allowed to range from 228V to 252V (+/-5%). If a 230V motor has +/-10% range it can go from 207V to 253V, which covers the utility range plus branch circuit voltage drop.
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