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plunger
11-27-2011, 12:17 AM
I bought a couple of motors at an auction.One of the motors is a 5 hp motor but I notice the name plate says it is 60hz I am electrically challenged In my country we have 240v at 50hz. Will this motor run ? Or am I going to blow it up?I also bought this other motor that looks like a reduction gearbox of sorts with a built in handle .In homeshop fashion does anyone have a suggestion as to how the orange motor could be usefullhttp://i941.photobucket.com/albums/ad254/eugeneeman/007.jpg Regards Eugene

ftl
11-27-2011, 12:45 AM
If the voltage rating for the motor is 220 or 240 V it will probably be fine. It will turn a bit slower (50/60 * the nameplate speed). It may not produce full power, but should come close.

darryl
11-27-2011, 01:09 AM
You'll just have to try it. Some motors will work ok on the lower frequency while others will overheat. You can almost always run a 50 hz motor on 60 hz though. Voltage rating has to be right- you can't run a 110v motor on 220 without cooking something. Sometimes you'll have a problem with a 220 motor if your voltage is unusually high, like 260 or something.

plunger
11-27-2011, 01:16 AM
The motor is rated at 230v and we work on 240 v here in s africa

lakeside53
11-27-2011, 01:22 AM
One of the USA standard mains voltage is also 480/240 volts, but the motor are often rated at 460/230 to account for wiring losses. The motor will work fine on your system

The Artful Bodger
11-27-2011, 01:38 AM
Hi Plunger, I am sure the motor will be fine but avoid stalling it as it may be more vulnerable to damage in that situation on a lower mains frequency.


The orange motor it totally useless, please send it to me for safe disposal!:)

lakeside53
11-27-2011, 01:43 AM
I don't believe its more likely to stall or be damaged on 50hz. If anything, the locked rotor curent will be lower on 50hz than 60hz.

The start capacitor (that dented round structure on top) will probably work fine as is, but if the startup seems labored, increase the capacitance about 20%

The orange motor: looks like someone put a handle on it to give accurate positioning downstream, or, a cheap hand-powered reduction gearbox for something. Might want to take the handle off before applying power ;)

Evan
11-27-2011, 02:01 AM
The orange motor looks like it might make a nice wet and dry grinder. Dry on the high speed end and a wet wheel on the slow end. They sell grinders with a similar configuration and since that motor is sealed it would work well in the service.

plunger
11-27-2011, 02:25 AM
Evan I quickly googled a wet and dry grinder and most stuff that came up referred to kitchen stuff. Somehow I have a feeling you have a different idea for this. What is a wet and dry grinder useful for in a homeshop

The Artful Bodger
11-27-2011, 03:48 AM
. If anything, the locked rotor curent will be lower on 50hz than 60hz.



Can you explain this please as I assumed the impedance would be lower with the lower mains frequency? Thanks.:)

plunger
11-27-2011, 04:06 AM
I hate being so dumb with motors. I am feeling that my auction day is going to work out to be a flop. I took the motor apart as I could see a wasps nest in it. The motor looks hardly used.I then fired it up by holding the wires on the lugs This immediately burned up the wires in my hand as it arced the lug off. I then did a more permanent connection and it tripped the house.Then I took the two covers off where the capacitors are. The capacitors have been stolen.I then tried to spin it by hand and it seemed to start for a short while and then tripped the house. Could someone explain what these capacitors do and what type of caps are they. If I had to spin it by hand should it not work without caps. Is it still possible that if I put caps in it might work or does it sound like the magic smoke has escaped? How would I know what type and size of cap this takes.Do you think 5 hp draws to much start up current and so trips the house. Its on a 20 amp circuit breaker.Or is this the function of the caps. This is a motor made by emmerson in the states and is rated for 230volts. Is your power different. It also has 1 phase written on the info plate Here in s africa our power is single phase 240volt We have a live a neutral and a earth. Why in the states do they talk about dual phase. I am getting confused.

garagemark
11-27-2011, 06:46 AM
You will definitely need the caps. They act as a kind of "booster" to either get things going or to keep things going (start or run, or sometimes both).

As I do not really understand your power system, you say you have a hot wire with 230 volts, a neutral, and earth ground? If so, then your motor probably won't work. 230 volt single phase in a motor is usually two 120 volt hot wires, with no neutral used (only use an earth ground to the motor case for safety). So if you are hooking up to an actual "neutral" (which is essentially a ground), you are shorting the motor out, which in turn is tripping your house mains.

By the way, I like the little orange motor, I could see all kinds of uses for it. The wet/ dry grinder could be a good choice if the geared side isn't too fast.

DENedbalek
11-27-2011, 07:30 AM
I hate being so dumb with motors. I am feeling that my auction day is going to work out to be a flop. I took the motor apart as I could see a wasps nest in it. The motor looks hardly used.I then fired it up by holding the wires on the lugs This immediately burned up the wires in my hand as it arced the lug off. I then did a more permanent connection and it tripped the house.Then I took the two covers off where the capacitors are. The capacitors have been stolen.I then tried to spin it by hand and it seemed to start for a short while and then tripped the house. Could someone explain what these capacitors do and what type of caps are they. If I had to spin it by hand should it not work without caps. Is it still possible that if I put caps in it might work or does it sound like the magic smoke has escaped? How would I know what type and size of cap this takes.Do you think 5 hp draws to much start up current and so trips the house. Its on a 20 amp circuit breaker.Or is this the function of the caps. This is a motor made by emmerson in the states and is rated for 230volts. Is your power different. It also has 1 phase written on the info plate Here in s africa our power is single phase 240volt We have a live a neutral and a earth. Why in the states do they talk about dual phase. I am getting confused.

Trying to spin it by hand and having it try to run sounds to me like you may have a good motor. Based on what you've said about it so far, I suspect that you have a start capacitor style motor. The wasp nest needs to come out of there, just clean it out without damaging the laquer on the windings. If necessary, take the end bell off of the motor and wash the dirt & mud out of it. Let it dry completely before reassembly. With a start capacitor, you may have a mechanism on the shaft (centrifugal switch) to drop the start winding circuit out after the motor comes up to speed. Be careful to not damage it when disassembling the motor.

The 240 v / 50 Hz should work just fine with that motor. On most motors designed for 240v here in the US, you assume the line voltage is comprised of two 120v lines 180 degrees apart (meaning that you get a voltage measurement of 240v between the two lines). What you have is 240v on line 1 and 0v on the other line. The motor does not care how it gets the 240v across the windings.

If you do a search for the model number of the motor you may be able to find the mfr wiring diagrams and parts information. Key here is to get the correct capacitor for it. I have some reference materials I can dig through if you can put a decent picture of the nameplate in a post here (or send me a PM).

Dwayne

J Tiers
11-27-2011, 11:13 AM
if there are two capacitors, one will be for starting only, and the one stays in-circuit for running.

You need both.

I suggest posting a good clear picture of the nameplate. That usually has quite a good amount of info that you need.

There is no guarantee that the motor is good, of course, but also no guarantee that it is wired correctly. There are several wiring errors that can cause exactly what you see. And of course not having the start and run capacitors will be an issue.

Even when correctly wired and with all good parts, a 5 HP motor can easily draw 7 or 8 amps with no load. The starting current will be maybe 5 to 6 times that much (or more at 50 Hz) and is findable from the nameplate data. The motor could easily have been drawing somewhere above 40 amps in the condition you tested.

There is a chance that the motor will not work well on 50 Hz, but we don't know that yet. Nameplate data will help determine that. Since it is there in SA, and it apparently seems to have been used, but does not smell burnt up, it probably works on your current.

Naturally if you run it with a VFD, everything will be perfectly fine regardless. I assume you don't plan to.

lakeside53
11-27-2011, 11:48 AM
Can you explain this please as I assumed the impedance would be lower with the lower mains frequency? Thanks.:)


No I can't explain. It was late and I got it backwards. That's what happens when you spend 1/2 of your life in 50 hz countries, and a lot of time where they use both! Sad.. I actually get paid for similar advise. lol... (note to self - don't post if you've had a few). :D


Plunger : yes, your 20amp breaker is insufficient to run a 5hp motor starting as you did - the surge from the few rpm to it's slip/synchonous speed will be too much. You can get over much of this by bolting it to a bench and using another motor to spin it up to near the correct speed, then cut power to the drive motor and apply to the 5hp. Similar to a pony motor on and RPC. Even then, a 30-40 amp breaker would be better.

As others have requested - post a pic of the motor plate.

lakeside53
11-27-2011, 12:02 PM
This is a motor made by emmerson in the states and is rated for 230volts. Is your power different. It also has 1 phase written on the info plate Here in s africa our power is single phase 240volt We have a live a neutral and a earth. Why in the states do they talk about dual phase. I am getting confused.

We don't have "dual phase" - just single phase. The typical residential power is 240 volt with a center tap on the 240 winding providing the neutral connection. This gives 120 to either of the "hot" legs or 240 if you ignore the neutral. Lower power appliances, typicial room outlets and lights all run from the 120 volt legs; ovens, dryers, hot water tanks etc are usually 240 volt. The advantage of ours is that the maximum potential to ground is 120 volts (even when usings the 240 volt feed); the disadvantage is we run heavier wire than you for the same power with lower voltage appliances.

The "180" you see people posting about is a little misleading. The 240 is not made from 2 legs of 120v 180 degrees apart. The 240 is just like yours - a sine wave. Yours has one leg grounded, ours has the center tap.

mickeyf
11-27-2011, 12:13 PM
That doohicky hanging off the orange motor, by the way, appears to be a variable speed pulley. Increasing the tension on the attached belt works against the spring, causing the belt to ride more deeply in the groove of the pulley and effectively decreasing its diameter, which then alters the ratio between the two pulleys and decreases the speed at the driven pulley. I have seen a couple of variations on the exact mechanism used.

They were popular back in the day, before VFDs and brushless DC motors. My Logan shaper uses one, and I recently got an old free treadmill, in which I expected to find a variable speed DC motor, but instead found an ordinary AC motor and one of these pulleys.

If the nameplate is legible, the manufacturer would be able to tell you what values you need for the capacitors, and what the internal wiring diagram of the motor is so that you know how to connect them. The are, as was mentioned, necessary. What they do is shift the phase between different windings of the motor so that the magnetic fields are 'out of sync", which is what causes it to spin. Often there is a "starting capacitor" which is connected only to the starting winding. The start winding is switched out when the motor comes up to speed, often by use of a centrifugally activated switch on the motor shaft, occasionally by some other mechanism such as an external current sensing relay.

My guess would be that the capacitors where either removed to fix some other motor, or perhaps failed themselves and were removed for replacement then became separated from the rest of the motor and forgotten. If the motor seems otherwise new, probably the first. We see a fair amount of Government surplus in which otherwise new equipment has been cannibalized for parts, rendered useless, and sold at auction to those lucky enough to know what they're getting and how to resurrect it.

lakeside53
11-27-2011, 12:20 PM
I don't see any split in the sheeve though. Looks like a shock absorber to me.

Evan
11-27-2011, 01:00 PM
We don't have "dual phase" - just single phase.

The proper name is split phase.

The Artful Bodger
11-27-2011, 02:34 PM
No I can't explain. It was late and I got it backwards. That's what happens when you spend 1/2 of your life in 50 hz countries, and a lot of time where they use both! Sad.. I actually get paid for similar advise. lol... (note to self - don't post if you've had a few). :D


Im cool!


I think Japan is one of those countries, we had problems in North Korea where the mains was 42Hz (should have been 50) which was really odd as the local power station was right on frequency, never did figure out how the frequency changed in the network.

I used to work at a hotel which had its own hydro, every time it rained too hard and leaves blocked the intake the hydro would slow, the lights dimmed, the frequency sagged and all the American made appliances would smoke. Transformers in the Collins transmitters in my radio station would begin to buzz and if I was too slow with the cut out they would smoke too.

Evan
11-27-2011, 04:22 PM
Here is a wet/dry grinder. That motor looks ideal for it.

http://ixian.ca/pics9/wetgrinder.jpg

darryl
11-27-2011, 06:18 PM
I think the spring loaded pulley is just a clutch- something to let the pulley keep spinning if the output shaft jams.

mickeyf
11-28-2011, 11:19 PM
So the spring loaded pulley has 1 vote for a variable speed pulley, 1 vote for a shock absorber, and 1 vote for a clutch.

If the pulley does not have two separable halves then I'm definitely wrong - hard to tell from the photo. Perhaps the OP can solve the mystery?

J Tiers
11-28-2011, 11:24 PM
So the spring loaded pulley has 1 vote for a variable speed pulley, 1 vote for a shock absorber, and 1 vote for a clutch.



I have no particular opinion...... but I DO have two generally similar pulleys that are variable speed components...... They have covers over their springs, but.....

That said, on the "inside" surface of the pulley is a large diameter hub that could easily be a clutch element..... But clutches usually have the spring "decoupled" from the rotating parts, because the spring would get worn, or would wear what it pushes on otherwise. That one doesn't..... maybe it's in the shaft part.

Evan
11-29-2011, 12:09 AM
It's a slip clutch. Because it's a worm drive it needs something to limit the delivered torque so it doesn't fry the belt or break things or hurt somebody if the load is jammed.

plunger
11-29-2011, 12:32 AM
I think evan has it right.The pulley is not split .The pulley rotates at 32rpm Is this too slow for a wet grinder? Any other uses?

lakeside53
11-29-2011, 12:56 AM
Depends on the size of the wheel. I have a 10 inch at 80 rpm (Tormek).

The Artful Bodger
11-29-2011, 01:32 AM
It will have bags of torque at 32rpm, maybe you could connect it to a capstan drum and use it as a hoist or winch.

Maybe a gate opener?

Evan
11-29-2011, 01:42 AM
Are you certain it's 32 rpm? It doesn't look like there is room for that much gearing. That would require something like almost 100 to 1 if its a two pole motor. 320 rpm would make much more sense.

How many turns of the hand crank does it take for one turn of the side output?

jack3140
11-29-2011, 08:21 PM
Evan I quickly googled a wet and dry grinder and most stuff that came up referred to kitchen stuff. Somehow I have a feeling you have a different idea for this. What is a wet and dry grinder useful for in a homeshop
i have one of those it does a great job sharpening my wood chisels etc

sch
11-29-2011, 09:19 PM
I have a 60hz 5hp 1ph 230V GE motor running my ancient wood planer
and uncorking the box I find 2 larger gauge stiff (ie probably not stranded)
black wires hooked directly to the 230V line and two smaller red stranded
wires that hook as follows: one red goes to one side of the 230V line
the other red goes into one capacitor which is in series with a second identical
capacitor that hooks into the other side of the 230V line. The caps are
labeled motor start 125 VAC 550-650mfd. This suggests that my motor
is cap start motor and the start cap is effectively 250VAC 275-325 mfd.
Here is a reference as to wiring: http://igor.chudov.com/manuals/ElectricMotors.pdf
(It appears to be a 20-30yr old article from Live Steam)
The lack of a capacitor means the motor is dropped across the line in an effectively
locked rotor condition and will be drawing huge amps, only modestly less than the
effective dc resistance of the windings would allow, hence your blown ckt breaker.
Get the capacitor in there and the motor will likely run fine. You will have to open up
the connection box and eyeball the wires to see which is which if the motor label is
not helpful.