Need help converting motor from 110 to 220 volts
Login to Your Account
Likes:  0

# Thread: Need help converting motor from 110 to 220 volts

1. Titanium
Join Date
Jan 2005
Location
Roseville, CA
Posts
3,857
Post Thanks / Like
Likes (Given)
26
Likes (Received)
19
I have a small vertical mill that has a 1 1/2 HP, single phase motor (Taiwanese)that is convertible on voltage. When I got it, it was running on 110 volts, but takes 20 amps on one leg. I want to convert it to 220 to reduce the amperage per leg and I also want to hook it to a reversing switch.

It has six motor leads that are labeled as follows:

1-A - red \
1 - black - tied together
2 - blue /

2-A - red \
3 - yellow - tied together
4 - white /

Which leads would I connect together to make it run on 220 volts and how would these leads connect to a standard reversing drum switch to allow reversing. I understand that it cannot be reversed under power because it is not three phase.

Thanks for your help.

2. Referring to the diagram shown below:

Your first task will be to assign to the six wires these functions: start winding-start, start winding-finish, run winding A-start, run winding A-finish, run winding B-start and run winding B-finish.

Then, you will connect the two run windings in series.

Finally, you will connect the start winding from either L1 or L2 to the center of the series-connected run winding.

Each drum switch is somewhat different, and in the 120 volt case, all six wires will be connected to the switch, whereas in the 240 volt case, only five wires will be connected.

3. Titanium
Join Date
Jan 2005
Location
Roseville, CA
Posts
3,857
Post Thanks / Like
Likes (Given)
26
Likes (Received)
19
Peter - Thanks for your response, but I have another question, seeing as how I am a bit electrically challenged, when it comes to motors.

You said: "Your first task will be to assign to the six wires these functions: start winding-start, start winding-finish, run winding A-start, run winding A-finish, run winding B-start and run winding B-finish."

My question is, how do I assign these functions? What test? do I need to do to make those determinations?

I should have added in my original post, that there is no diagram anywhere on what leads to change to convert to 220. Usually it is inside the wire connection box, but not this time.

4. You already know how the motor is supposed to be connected for 120 volts, so you can assume that L1 corresponds to the start of each of the three functional units enclosed within the boxes labeled "?". Clearly, L2 corresponds to the finish of those functional units. (Or vice versa).

Label the wires START or FINISH, as appropriate.

Use a DVM or other available instrument to measure the resistance (continuity) of the three boxes.

If there is nearly a short circuit, than that box contains a run winding.

Label these as RUN A WINDING and RUN B WINDING, as appropriate.

If there is an open circuit, or a short circuit which eventually becomes an open circuit, then that box contains the start winding.

Label these as START WINDING.

You should now have six wires, labeled START WINDING - START, START WINDING - FINISH, RUN A WINDING - START, RUN A WINDING - FINISH, RUN B WINDING - START and RUN B WINDING - FINISH.

(In the previously posted schematic diagram, the "dot" indicates the START of a winding).

Once the two run windings have been identified, connect them in series connection, and connect the start winding to the middle of this series connection.

#### Posting Permissions

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