Running a 140W Single-Phase 60Hz Motor on 50Hz Power or 50Hz Motor on 60Hz Network

I have a question, what will happen if I connect a single-phase 140W 60Hz motor to our standard 50Hz network and vice versa, the same motor but in the 50Hz version to the 60Hz network (ship`s network)

Don`t worry, nothing will happen. It will only have a slightly lower number of revolutions per minute.

what about 50 Hz to 60 Hz, do the motors differ in the number of poles (coils)?

Generally, you have nothing to worry about. As Col. writes:
above, the engine will only have changed revolutions.

What is the point of producing an engine with 50Hz markings and the same engine model with 60Hz. Information about the change in rotational speed is obvious. There is definitely some difference in the construction of these engines

There is simply no difference in the country of origin of this engine, the network frequency is 60 Hz and that`s it.

At 50Hz there are slightly more turns, and at 60Hz there are fewer turns. A 60Hz motor connected to a 50Hz network will heat up a little, but should not be damaged, while on the other hand the motor will run even longer and nothing will happen to it.

kierbedz4 wrote:

There is simply no difference in the country of origin of this engine, the network frequency is 60 Hz and that`s it.

it`s not about another country, but about ships there, the voltages and frequencies are different, e.g. 440v 60Hz or 440V 50Hz. 400V 50Hz and 1-phase 240V networks obtained from the transformation of a 3-phase network (no working zero). At the beginning of the topic I wrote that it concerns ships. Opinions are divided even among ship electricians, some say that devices with a "land" frequency they get damaged quickly and others say that nothing will happen to them. I understand my friend`s answer about the number of turns in the coils and is the wire diameter the same? One more important thing: I am interested in 3-phase and 1-phase motors with a capacitor.

Added after 9 [minutes]:

and one more thing, I once had to turn on the flex on the ship and I thought it was broken, I even disassembled it at the fault site and couldn`t find how. It turned out that I had to hold the switch longer and it worked after some time. This experience shows that there is an important difference, probably the power of my flex has also decreased

Where do YOU study? If you can`t find a solution here, contact me as it depends on ships and devices, first of all, and no one can cheat physics.

Sometimes I see "multi-system" motors described as 320-480V 50-60Hz. Africa or Australia - it doesn`t matter to him. In America, the home network is poor (110), and there are many standards in the industry, so they have to somehow manage.

I think that if the rated current is not exceeded, nothing can happen, but I will ask President Wałęsa. :D

Unless salt water gets inside.

uni_technika wrote:

I have a question, what will happen if I connect a single-phase 140W 60Hz motor to our standard 50Hz network?

I understand that we are writing about a capacitor induction motor, or possibly a 3-phase induction motor.
1. It will get hotter. It should have a reduced supply voltage by 1/6 compared to the nameplate.
2. Its revolutions will drop by approximately 1/6.
3. Its rated power will drop. By more than 1/6, because see 1.

Quote:

and vice versa, the same motor but in a 50 Hz version for a 60 Hz network (ship network)

1. Its rated torque will drop (because the supply voltage should be increased by 1/5, but it is not)
2. Its turnover will increase by approximately 1/5
3. It may get hotter due to more frequent remagnetization of the sheets, but this effect is compensated (probably with an excess) by 1.
4. The risk of capacitor damage increases (it does not like raising the frequency)
5. Theoretically, it will have more loaded bearings (due to 2.), but in the vast majority of cases they should be able to withstand such a "slight" overload.

The most important thing seems to be matching the supply voltages.

In the same way as transformers are wound, it also depends on how many turns are wound when powered at a different frequency. You can often find coils from contactors operating at two frequencies and different operating voltages are given. The thickness of the wire depends on the current consumed by the device.
Bonanza; in America there is no 110V voltage, it was changed to 120V a long time ago. Motors operating at 50Hz work smoothly in 60Hz installations, even though the voltage is sometimes higher.

Thank you to everyone who answered my question, especially krzychol66

I`m closing the topic

Hello !
In the 1970s and 1980s, I worked in a company producing single- and three-phase electric motors up to 1.5KW. I remember, we also produced single-phase 60Hz motors and they differed only in a different adjustment of the centrifugal switch.
The windings were the same as at 50Hz.
Regards. Stefan Poznań

Quote:

I understand that we are writing about a capacitor induction motor, or possibly a 3-phase induction motor.
1. It will get hotter. It should have a reduced supply voltage by 1/6 compared to the nameplate.
2. Its revolutions will drop, approximately by 1/6.
3. Its rated power will drop. By more than 1/6, because see 1.
Quote:

and vice versa, the same motor but in a 50 Hz version for a 60 Hz network (ship network)

1. Its rated torque will drop (because the supply voltage should be increased by 1/5, but it is not)
2. Its turnover will increase by approximately 1/5
3. It may get hotter due to more frequent remagnetization of the sheets, but this effect is compensated (probably with an excess) by 1.
4. The risk of capacitor damage increases (it does not like raising the frequency)
5. Theoretically, it will have more loaded bearings (due to 2.), but in the vast majority of cases they should be able to withstand such a "slight" overload.

Quite a strange theory, mechanically the motors can usually withstand at least twice the speed indicated on the nameplate, the revolutions do not change approximately, the revolutions change by exactly 1/6 when the network frequency is reduced from 60 to 50Hz, the revolutions of the induction motor depend linearly and not in approximately on the number of pole pairs and voltage frequency. When f is reduced, the engine cosφ increases and largely compensates for the change in torque. Moreover, motors are often frequency-controlled (inverters) and no harm is done to them. To sum up, the 60Hz motor, when connected to the 50Hz network, will rotate slower by 1/6 and the remaining performance will not lose more than a few%, of course while maintaining the rated supply voltage.

I agree with the previous author, there are some changes mentioned by krzychol66, but for an average user such a change is not important (just like changing the voltage from 220 to 230V). If only because the engines usually do not operate at 100% of their rated power (the engine is always selected slightly larger).
Moreover, many manufacturers provide on the plate the rated parameters that their motor achieves at both 50 and 60 Hz.

SzymonHK wrote:

Quite a strange theory, mechanically the engines can usually withstand at least twice as long as on the nameplate,

You should politely ask the manufacturer about this... one engine will last, the other will not...
There are usually no problems with "catching up" the engine to a frequency of 85Hz, but this is not a rule that can be blindly applied to all engines...

Quote:

the revolutions do not change approximately, the revolutions change by exactly 1/6 when the network frequency is reduced from 60 to 50 Hz, the revolutions of the induction motor depend linearly and not approximately on the number of pole pairs and voltage frequency.

Half-truth.
Turnover synchronous of an induction motor actually depend linearly, and not approximately, on the number of pole pairs and frequency.
Turnover real at a given load, they also depend on the mechanical characteristics of the engine, which in turn depend on a number of factors. E.g. from the supply voltage value.

Quote:

Moreover, motors are often frequency-controlled (inverters) and no harm is done to them.

However, it would be worth knowing that the inverter controls not only the frequency, but also the amplitude of the voltage supplying the motor. The simplest inverters adjust the voltage to the frequency according to the relationship U/f=const. More advanced ones adjust the voltage precisely to the previously measured motor characteristics and to the current load.
Failure to match the U/f would result in immediate saturation of the motor plates and burning of the windings at low frequencies.

Quote:

To sum up, the 60Hz motor, when connected to the 50Hz network, will rotate slower by 1/6 and the remaining performance will not lose more than a few%, of course while maintaining the rated supply voltage.

Well, if for my Dear Colleague 1/6 is a few %, then I have no more questions...
However, I am allergic to U/f=const. and the phenomenon of saturation of sheet metal...

There is one problem, a small problem, if you connect a device with a matching 50 Hz motor to a 60 Hz network, there will of course be greater mechanical resistance and the engine operating at higher speeds may not work in extreme cases.

Quote:

The synchronous rotation of an induction motor actually depends linearly, and not approximately, on the number of pole pairs and frequency.
The actual revolutions at a given load also depend on the mechanical characteristics of the engine, which in turn depends on many factors. E.g. from the supply voltage value.

A synchronous motor must run at synchronous speed within the permissible slip limits, otherwise it is no longer synchronous and the end of operation.

Quote:

You should politely ask the manufacturer about this... one engine will last, the other will not...

No motor up to 3000 rpm has a safety factor of less than 2.

Quote:

Failure to match the U/f would result in immediate saturation of the motor plates and burning of the windings at low frequencies.

We are not talking about changing the frequency from 60 to 2 Hz but to 50 Hz. Not all inverters treat U/f as an immutable parameter.

Quote:

Well, if for my Dear Colleague 1/6 is a few %, then I have no more questions...

I wrote that the speed will change by 1/6, other parameters such as power and torque will change much less, because when changing f, cosφ changes, when changing from 60 to 50 Hz in favor of the engine parameters, you also need to be aware of this.

As for the remagnetization of the sheets, the engine would have to have very high kW/dm3 parameters for it to be a problem.
And for a single-phase motor, when changing from 60 to 50Hz, it may be necessary to increase the capacitance of the starting phase capacitor.

To sum up, it is worth knowing that when changing the power supply frequency, such as 60/50Hz, problems may arise, and each case is worth analyzing individually.

I have a 4kW engine working with a suction pump, the nameplate indicates a delta connection and an operating frequency of 60Hz. When connected to the network, it blows the 25A fuses, when connected to a star, it works but gets very hot. Starting from a star and switching to a delta also causes plugs. Other the motor for the pod is of a similar design, but on the plate it says 50Hz, it works without any problems in a delta connection. Could this be due to an inappropriate network frequency?

Maybe the wires are reversed when switching the whistle-delta and the revolutions change. It is necessary to check whether the resistance of the windings is the same and whether there is no breakdown. The motor must be adapted to change the star-delta connection. The coils are wound with different voltages. It`s best to take a photo of the nameplate on the engine. Each motor will work after changing the frequency from 60 to 50Hz. Only the speed and partly the engine power will decrease.

it says 220V on the plate, I don`t know if it matters. Today we connected this engine without load and it also blows the fuses. It should start with a delta connection without any problems.

Maybe provide all the data from the plate, we won`t have to guess what`s wrong. Because now it turns out that it should not work in a triangle at 400V.

ok, tomorrow I will send a photo or write down the data from the plate, I will try to send the plate around 9 am, I would be grateful for a quick answer. Does the 220V mean that this is a 120V 60Hz engine for the American market?

Hello
If the sign says something like this:
220/400 D/Y - such a motor cannot categorically operate in a triangle connected to the network. There is approximately 400V between phases in the network and therefore the motor must be connected in a star manner. If the engine overheats in the star, it means that it is simply overloaded and requires replacing with a larger one or reducing the load.

Either way, post a photo of the plate and everything will become clear.

There is a field on the tablet CONECTED Δ, the plate clearly indicates that the engine is to operate in a triangle

marchello wrote:

There is a field on the tablet CONECTED Δ, the plate clearly indicates that the engine is to operate in a triangle

And it seems that "220V" was also written there, and we do not have such a network (3x220V phase-to-phase).

In the American three-phase network there is 208V, sometimes 220V between the phases, and between the phases and neutral 120V. Therefore, this motor is not suitable for connection to a Polish installation without using a transformer or three-phase autotransformer. In America, engines are most often connected in a delta configuration and star-delta switches are rarely used.

Here is the nameplate


Speed 1720 rpm
voltage 220V
current 15 A
connection Δ
power 4 kW

This motor will not work in our 400V network. It can be connected via an inverter or rewound to the appropriate voltage.