Motor question (220 V mixer)

15 years ago

We had a mixer installed in the bakery where I work last week and it was immediately apparent that it couldn't do its job. It simply lacks power to pull loads that smaller mixers handle readily. It is not as "healthy" as the older one it replaced. It sounds fine when idling and will pull small loads adequately. When we tried to mix small doughs with it it started to smell hot so we stopped.

It's a Hobart 140 quart (refering to the size of the largest mixing bowl it accepts). It draws less than 20 amps under full load. The circuit it's wired into is the same one the other mixer was on.

We have techs coming in today to work on it, but I'm curious. Could its weakness be explained if one leg of the circuit were not live? Would running it with 110 V ruin the motor?

Thanks,

Mark

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Comments (11)

dave007700
15 years ago
If the motor is rated 220v and you are feeding it with 120v you will burn it up.
marknmt
Original Author
15 years ago
Thanks- That's a point of confusion for me, as I know that some motors can be wired to run on 110 V or 220 V.

I appreciate your help.
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Ron Natalie
15 years ago
Yes, but if it's wired up for 220 you need to feed it with 120. Motors aren't like computer power supplies that can accept a wide range of input voltages.
bus_driver
15 years ago
"Yes, but if it's wired up for 220 you need to feed it with 120." I suspect that this was a typo.
Many motors can be operated on multiple voltages, but there is a specific wiring diagram for each voltage and it must be the proper hookpup for the specific voltage supplied. Think of it as feeding a motor. Motors have very delicate digestive systems and must be fed the proper diet.
wirenut1110
15 years ago
Are you sure you don't have 208 volts? If your bakery is fed with a 3 phase service this may be the case.

If the motor is 230 volt and running on 208 it won't really hurt the motor but you'll lose about 20-25% of the torque due to slippage and this may be causing it to overheat.

Just a thought.
marknmt
Original Author
15 years ago
Thanks for the help.

Tech came yesterday and found the clutch out of adjustment. (It's a "new" rebuilt) You'd think they would know how to check for that during rebuilding! Works fine now.

The store is wired for three phase, I'm pretty sure, but I'm almost positive that the service to the mixer is two phase. There's a total of three wires into the disconnect and I assume it's two 110V legs and a ground. I may misunderstand but I believe that's two phase.

(I need to take that Siemens tutorial that was linked here a couple of years ago again- anybody happen to have the link handy?

Thanks again for all the information.

Best,

M
joed
15 years ago
IF a 220 device lost one of the hot legs it would not be getting 120 volts. It would be getting zero.
marknmt
Original Author
15 years ago
>>IF a 220 device lost one of the hot legs it would not be getting 120 volts. It would be getting zero.I get that- I was thinking it could be an issue in the machine- we've seen something like that before on a different brand mixer (Boku)but I don't remember the details.

Thanks again.

M
brickeyee
15 years ago
"I may misunderstand but I believe that's two phase."

It is either single phase with the legs 180 degrees apart, or 3-phase with a missing phase.

The phases in 3-phase power are 120 degrees apart.

the phases in 2-phase power are 90 degrees apart and ot requires four conductors, one of the reasons it quickly disappeared when 3-phase power was invented.

Delta 3-phase only needs 3 conductors.
garymunson_2009
15 years ago
Since the discussion got into polyphase (3 phase), those discussing it may want to Google 'chorus motors' for an interesting application of 15 phase motors......
billhart
15 years ago
If the building has 3-phase, it may be either of two varieties. It could be 208 volts line-line which is 120 line-neutral, and you would lose some performance in a 240 volt motor.

Or it could be high-leg delta which provides ordinary household 120/240 single phase plus an additional conductor that allows for 240V 3-phase loads. Or it could be that same wiring arrangement with the voltages scaled back a few percent to give an intermediate 3-phase voltage.

Motor question (220 V mixer)

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dave007700

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Motor question (220 V mixer)

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