kmg electrical question.......

ryan9977

ryan9977

Joined
Feb 16, 2006
Messages
1,962
ok so bear in mind i have ZERO knowledge of electricity....well i know u can get electricuted!.....anyway i talked to an electrician about getting an outlet for a kmg....he said he had to know the volts amps and watts i think....anyway i sent an email to rob and he was more than happy to look up the infor for me once i tell him which motor i was looking at.....i will most likely get the 1.5 hp or 2hp version......soooooo.....say i get the 1.5 hp- my outlet is all good and everything......and then down the road i switch to a bigger hp motor?......

1)do i need a new plug?

2)will i have problems with the power to the shop?

3)anything i should be concerned about or talk to an electrician about?


thanks for any info....please try and word any electrical type responses so i can understand them:D.....ryan
 
There should be a name plate on the machine if it's 120v and has a normal plug your set with an existing wall outlet. If the voltage is say 240 you may need a new outlet and possibly a new line run all together if it requires a neutral. How man prongs are on the plug of the machine?
 
I am a disabled comercial electricain. first thing to ask is:
how many amps does the motor need?? 20 amp 30 amps
is it 110 or 220 volts.
I would only buy spec plugs. they are better quality.
I would put this motor on it's own breaker so nothing else would trip it.
I would over size the wire too. if it is a 20 amp motor then you could use 12 awg wire but I would set it up to 10awg wire. If it is a 30amp motor the you could use 10awg but I would use 8awg wire instead. The bigger the wire the less Resistance it has.
if you have any other question please email me at ginrickie1@juno.com
 
1 HP = 746 Watts

Divide that by motor voltage to discern the current (Amps)

1 HP motor @120V. = 6.22A

1 HP motor @240v. = 3.11A

I'm assuming this is residential (single phase)
 
Ryan , make the decision on what you want or going to get and then tells us what Rob told you . No one can help completely with out all the info and either can your electrician .
Also Richard is giving good recommendations . I also would only get a 220 volt set up . Many reasons .
 
thanks evryone....jack that makes sense.....i don't have a grinder yet.....was just talking to an electrician to see what it would cost for all the electrical work.....thanks for all the help.....i guess the one question i still had was.....say if i get the 1.5 hp kmg......and then down the road i upgrade to a variable speed 3hp package?.....will that matter?......that was the main thing i was worried about......i put all the money into the electrical and in a few years i would have to redo something.....that's what i was worried about.....ryan
 
Brennanscott said:
1 HP = 746 Watts

Divide that by motor voltage to discern the current (Amps)

1 HP motor @120V. = 6.22A

1 HP motor @240v. = 3.11A

I'm assuming this is residential (single phase)
Click to expand...

Close, but you forgot to add in the motor inefficiency factor. Single phase motors are usually at best around .67 efficency.

Your typical good single phase 1hp motor is going to be 13 amps on 110 and 6.5 on 220
 
If you will go ahead and use bigger wire now, you will not have to worry about the motor change later. 10 AWG should more than enough, but the electrician should have an idea, if you tell him you want 220 volts with a max of 3 HP.
 
Justin.Mercier said:
Close, but you forgot to add in the motor inefficiency factor. Single phase motors are usually at best around .67 efficency.

Your typical good single phase 1hp motor is going to be 13 amps on 110 and 6.5 on 220
Click to expand...

He didn't give an eff% rating. When he gets it it will probably be about 50%

It will end up being in the 9 amp range @120v. or 6 amp range @ 240v.

Anyway, just run #12 gauge wire anyway. (for a standard 20 Amp circuit) and make it a dedicated circuit if possible.

#14 would be fine but you sound like you might want to upgrade things anyway.

Of course the best way has already been mentioned (check the motor nameplate)
 
Brennanscott said:
He didn't give an eff% rating. When he gets it it will probably be about 50%

It will end up being in the 9 amp range @120v. or 6 amp range @ 240v.

Anyway, just run #12 gauge wire anyway. (for a standard 20 Amp circuit) and make it a dedicated circuit if possible.

#14 would be fine but you sound like you might want to upgrade things anyway.

Of course the best way has already been mentioned (check the motor nameplate)
Click to expand...

14 awg is only good for 15amp. The reason you over size the wire is less Resistance means less cost for your electric bill. The cost factor for the different size of wire is pennies.
 
I have a few thoughts:

The 1-1/2 motor is by far the most popular size that we sell.. period. This is because it will plug into a standard 110V outlet and run. It is very convinient and 1-1/2 hp is about the max power that can be extracted from these standard outlets.

So, if you want the convinience of being able to plug the grinder into a regular outlet...then the 1-1/2 hp motor is the only choice. No need for special electrical set-up....just plug it in and start grinding.


If you are considering Variable speed.....1-1/2 hp and 2 hp will cost the same for the equipment....but 2 hp exceeds that power threshold limitation of the 110V outlet and will have to run on 220V. If 220V is available, then use it with a 2hp motor. It is the same price. In this case, you will want a 20A 220V plug and dedicated outlet.

If you decided to run the 3hp package, the VFD spec is for a 30A 220V plug and outlet. However, we run the 3 hp here in the shop on a 20A circuit and have never tripped it. My thinking is that the 30A spec is overkill...but that is the spec from the VFD manufacturer.

One more note about VFDs...they will not run on GFCI outlets. This comes into play on newer built homes and shops where the code requires these circuits where there is a possiblity of water presence...such as kitchens, bathrooms and garages. For our home shops...this is mainly related to 110V outlets.

A true 1-1/2 HP industrial motor will draw between 15-20 amps full load. This is ussually the size of the circuit breakers in our shops. So, the 1-1/2 hp motor is running on the edge of the electrical power limit. There are a lot of "over rated" motors out there that boost some creative claims on power....such as the 7 peak hp shop vac from Lowes.....that one kills me!!! So, it's likely that most motors that are rated at 1-1/2 hp will draw a little less. Our leeson motor is at 17Amps full load. We run it on a 15A circuit and have little troubles. We will occasionally trip the breaker when we have other equipment running on the same circuit...but otherwise the performance is very acceptable.

Ryan, my thoughts are this: if you plan to use a 1-1/2 hp motor....then you don't need to do anything in advance with an electrician....just plug it in and run it when it arrives.

But if you go the variable speed route..then the electrician will need to install a 20A, 220V outlet for a 2hp package....and a 30A 220V outlet for a 3hp package.

I hope this helps.

-Rob
 
At houses the rec are usually 15 amp 14 awg wire. The also run other things on that breaker too and that is why you want a separate breaker for your motor. If your panel is in the garage then it should not cost that much. You pull too much voltage through you wire you can cook the wire and cause a fire. I have seen it done. That is why I over size the wire just so that cant happened. It is better to be safe than sorry later.
 
richard thurman said:
14 awg is only good for 15amp. The reason you over size the wire is less Resistance means less cost for your electric bill. The cost factor for the different size of wire is pennies.
Click to expand...





And to run anything on 240V. as opposed to 120V. cuts the current usage in half.

I doubt resistance is gonna play much of a factor here unless the run is so ridiculously long that voltage drop would start to factor in.

Then bring in the inductive vs. resistive load thing.

As far as the difference being pennies. I wish it was. I'm an electrical contractor and let me tell you, the prices on copper these days? You would think it's gold.

This is why all those houses burned down in the seventies from using AL conductors in the romex. What a nightmare that crap is. :eek:
 
One more thing you need to know Ryan before you decide on the plug and play set up . As Rob said , the plug and play will max out that circuit on 110 , so make sure no other stuff is sharing that circuit . In one old house I had the garage circuit was shared with some outlets in the living room . Of course as soon as you plug it in and trip a breaker you will find this out .
 
Brennanscott said:
And to run anything on 240V. as opposed to 120V. cuts the current usage in half.

I doubt resistance is gonna play much of a factor here unless the run is so ridiculously long that voltage drop would start to factor in.

Then bring in the inductive vs. resistive load thing.

As far as the difference being pennies. I wish it was. I'm an electrical contractor and let me tell you, the prices on copper these days? You would think it's gold.

This is why all those houses burned down in the seventies from using AL conductors in the romex. What a nightmare that crap is. :eek:
Click to expand...

where are you a contractor at?? I am looking at the cost of materail under $75.00 and I think that is a bit high. plus you need the cost of the labor of the electricain that is going to do the work for you.
 
thanks alot guys....rob you answered a bunch of questions for me....thanks....

i actually was gonna go with the 220 for the kmg because i was gonan get an evenheat eventually too ....so i had the electrician to cost out the work.....unfortunately i need a service upgrade.....i have an older house and i guess the codes back then let u use a lower amp.....i showed him the stats on the evenheat and he said no way i could run it on what i have coming into my house.....the bad thing is it's expensive.....and he might have to dig up my driveway......anyway thanks for all the replies....it helped out with my questions.....i just need to save a little more first.....ryan
 
You must log in or register to reply here.
Back
Top