# Thread: Convert 480V current to 208V current

1. Junior Member
Join Date
Dec 2017
Location
CA
Posts
2

## Convert 480V current to 208V current

Hello,

Is there a specific equation I can use to convert amperage in 480V to 208V? I've been searching the web but can't find a precise formula to use.

Thanks

2. ?????

V480 x I480 = V208 x I208
for constant power

3. Senior Member
Join Date
Mar 2003
Location
New York
Posts
868
Are you trying to figure transformer primary/ secondary?

4. You could just do a ratio of the 480 volts to 208 volts. For volts 480/208 or 2.3 to 1. For amps 1 to 2.3.

Ex. 480v and 10 amps = 208v and 23 amps.

5. Senior Member
Join Date
Apr 2009
Location
Williamsburg, VA
Posts
4,738
Originally Posted by baserunner4
Hello,

Is there a specific equation I can use to convert amperage in 480V to 208V? I've been searching the web but can't find a precise formula to use.

Thanks
If they are both single phase or both three phase, you just multiply the current on the primary side by 480 volts, then divide by 208 volts.

6. Originally Posted by baserunner4
Hello,

Is there a specific equation I can use to convert amperage in 480V to 208V? I've been searching the web but can't find a precise formula to use.

Thanks
what are you a student of?
this is one of the most basic principles
P in = P out for a xfmr (or any device, in this case elec:elec, sometimes elec:mech or the inverse, sometimes thermal:mech, etc)
P = i x v for 1 ph and sqrt3 x i x v for 3 ph

7. Senior Member
Join Date
Oct 2009
Location
Austin, TX, USA
Posts
9,096
Originally Posted by baserunner4
Hello,

Is there a specific equation I can use to convert amperage in 480V to 208V? I've been searching the web but can't find a precise formula to use.

Thanks
Yes. I @208V = I @480V (480/208)

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•