AC motor and power connection

[Clintonb]

I am attempting a project that requires a heavy duty electrical motor. I was thinking of using an AC motor from a fan on the condenser of a walk in freezer. I cannot remember how the wiring was done and it was a three phase setup on the compressor but I'm sure it was a single phase motor. There are three pins on the power of the motor and I'm trying to understand which pin is for what. Would it be a good idea if I slowed the mortor down to use it as an actuator?

 

[Darkwood]

This is not a project for DIY ... their are many variants of motor and many parameters that can vary from speed, torque, voltage, control methods etc etc the list is long.... you only give us - 'Im sure it was single phase' this isn't written with confidence needed for us to start to help you.... it shows this is well out of your league.

You dont tell us the project?
You dont tell us your limitations?
You suggest the compressor is a 3ph set up on your compressor so its unlikely that a 1ph motor will be used...?
You say the motor duty is some kind of actuator .please expand on that?
You want to slow the motor down...What speed is the motor? What speed do you require?
How are you controlling the motor?
What protection system will you be implementing?
You say heavy duty motor ....please expand on your meaning of heavy duty....do you mean a standard induction motor of the shelf say 1.5kw, 4kw, 7.5kw etc etc

 

[clematis432]

I am attempting a project that requires a heavy duty electrical motor. I was thinking of using an AC motor from a fan on the condenser of a walk in freezer. I cannot remember how the wiring was done and it was a three phase setup on the compressor but I'm sure it was a single phase motor. There are three pins on the power of the motor and I'm trying to understand which pin is for what. Would it be a good idea if I slowed the mortor down to use it as an actuator?

The project your attempting, don,t attempt it !! No offence but your understanding of this project is minimal at best and probably dangerous at worst.

 

[Knobhead]

Being as you have a 3Ph supply, why not use it?

You’re post history is available to all.

 

[Darkwood]

Being as you have a 3Ph supply, why not use it?

You’re post history is available to all.

Yes checked it out myself ....hes surfaced after 3yrs in hiding wonder if he realised the basic laws of thermodynamics and that infra red isn't the only way to transmit heat yet

 

[Knobhead]

Always found a gas axe transmits heat fast. A lot more fun!

 

[Clintonb]

I'm going to ignore most of the replies as they're emotional and once again not very helpful. I am going to assist you on replying to a thread. First it is always good to assume people are not complete morons. I have reasonable experience in digital electronics and hence the whole actuator is going to be handled as such. I don't have a lot of extensive knowledge with AC motors and hence the question. The application is irrelevant because if the motor was not suitable then I'd probably not use it. When a person asks if a motor can be slowed for a purpose then he/she is asking wether slowing an ac motor would damage it because any clown with googlE would know it is possible. The question was regards to the three pins on a motor. A good answer would have been advice on determining what the pins are for and wether firstly it was in fact a 3 phase motor or not.

As for the infrared post let me update you on that because nobody got that either. My question wasn't about heat transfer it was about energy concervatio. If aadevice draws 550w it doesn't necessarily output 550w even though that is its rating. I'll let you google for the reason why.

 

[Darkwood]

Its just light hearted banter dont take offence....
No-one ever said you were a moron or assumed so, what was said was your lack of experience in this area shows as you confirm which can be a dangerous thing so giving advice on it can also be dangerous as anything missed or any incorrect info you might inadvertently supply due to your lack of knowledge in this field could put you in danger.
The questions above are all relevant .... motor speeds can be varied but in different ways for different types of motors and with a differing set of pro and cons- i.e If you fit a VSD to a standard induction motor this allows you to control the speed of the motor but with-in limits as precautions need to be taken when running lower speeds for any length of time with regards to the cooling of the motor. Just asking what the 3pins on the motor mean lacks info as you have not yet identified the motor type and voltage rating .... can you take a pic of the motor plate or relay the info of the plate to us.

The application of the motor can be crucial and as you openly admit your lack of knowledge in this area we need to make that judgement so again you are not supplying enough info ....it wouldn't be professional of us to just guess what motor you have and what the motor connections may be as we may be incorrect and could put you in a dangerous set-up hence we need all the info we can get which doesn't seem to be so forth-coming.

 

[Outspoken]

I am attempting a project that requires a heavy duty electrical motor. I was thinking of using an AC motor from a fan on the condenser of a walk in freezer. I cannot remember how the wiring was done and it was a three phase setup on the compressor but I'm sure it was a single phase motor. There are three pins on the power of the motor and I'm trying to understand which pin is for what. Would it be a good idea if I slowed the mortor down to use it as an actuator?

Does the motor have a capacitor attached to it? If the answer is yes then it is single phase, if it does not then it MAY be 3 phase.

If this is a 3 phase motor then the terminal cover will have 6 (SIX) brass terminals underneath and these will have links across depending on how the motor was connected up.

DW...IR is the ONLY way to transfer heat because Infra-Red is HEAT....if you change the form of radiation it is no longer heat...(Just being a pedantic git..sorry)

 

[Knobhead]

OK how about some pictures of this motor?

 

[Darkwood]

DW...IR is the ONLY way to transfer heat because Infra-Red is HEAT....if you change the form of radiation it is no longer heat...(Just being a pedantic git..sorry)

IR is NOT the only way to transfer heat as you put it.
Infra-red is not HEAT it is radiation
If you change the wavelength of the IR (change the form of radiation) it can still give energy to anything it hits that doesn't totally reflect it...... light can heat objects up even with IR filtered out and what about microwaves etc etc all used to transfer radiation which changes to heat energy when absorbed.

IR is electromagnetic radiation and not HEAT its just a wavelength of light and yes its one way of transferring energy (Heat is energy)but its is by far not the only way other common ways heat is transferred is by conduction and convection neither require IR, Infra-red is part of the thermal spectrum of light and if the surface it hits does not reflect IR then it will be fully or partly absorbed and this is where the energy changes state from radiation to thermal.

Hate to say your statement is totally incorrect and i suggest before replying you think carefully about your answer as i have studied the likes of quantum physics for 25+ yrs including the laws of classical thermodynamics as im a bit of a geek that way :biggrin: .....sorry if i also sounded pedantic

It did make me chuckle though trying to correct me but getting it so wrong ..... hope you take it in the humorous context in which i send this

 

[DPG]

Loving that reply. Daz

 

[Knobhead]

DW, Clear you're in box it's full!

 

[Knobhead]

Still like the gas axe! Direct heat but with a chemical reaction! Thermic is fun as well.

Heat in a flame is transferred directly or indirectly using hot gasses. A high resistance joint transfers heat by conduction. Induction heating is my favourite.

Heat transfer is a whole science of it’s own.

I’ve spent 40 years on kilns and furnaces. The main principal is transferring heat to accomplish a set aim.

Cement, iron, lime, ceramics and power generation all needed heat to be transferred one way or another. Played with them all and got burnt a few times on the way.