Help With A Hammond #4 Voltage

You want the cheapest way - just to test it? Okay, but there are some obvious risks! Just run it on single phase, that is all an RPC is doing. The idler motor is running on single phase.

1. Connect the motor per the low voltage arrangement on the motor plate.
2. Get ready to connect 240V single phase on any two of the motor leads (doesn't matter which two). Make sure you have a switch and are running through a 15 amp breaker. Clip a current meter onto one of the supply leads.
3. Spin the grinder up manually, which way does not matter. You need to get it going pretty good, at least half the rated speed. How you get it spinning is up to you.
4. Energize and it should come right up to rated speed. Take note of the current draw, if it is above nameplate , shut it off. If the current is way below name plate, the you probably have the wrong voltage.

Let us know hoe it works out.
 
On the connection tag it shows 9 wires? I only have 3.how would I wire for low voltage? At the forward-reverse switch there's 6 wires.thanks very much for helpful info.i do have a spare 2hp 3phase motor..if I knew how to wire for low voltage I'm thinking will spin up grinder like chipper advised and see what happens.thanks
 
bacause ther is only 3 wires, that indicates that the motor has ben tapped for single voltage use.
that voltage will either be 220/230 or 440/460
the three wires are all that is necessary to provide power to the motor.
if you change the phase on 2 conductors the motor will run in reverse

this motor may be difficult to start by hand.
i'm assuming you don't have 440/460v supply....
you can wrap a length of rope to the motor shaft and pull the rope like you'd start a lawnmower, while having single phase power connected to the motor.
if the motor runs without strange noises and seems to run well, you have found the correct operating voltage
if the motor sounds like it is laboring to run or makes heat or just doesn't sound right, you may have a motor wired for high voltage
if the motor kicks your breaker, that also may be a clue as to incorrect voltage- the amps go up if voltage is low
 
Thanks for info ulma Doctor ...I know I'm asking very basic questions.was going to run 220 to motor.hook up all three wires from supply to motor or just two hot??..this 3 phase is not sinking in..worked for ford dealers 27 years trouble shooting electrical problems..was simple compared to this..going to install pulley on motor shaft.use pony motor to spin..thanks for your time
 
you are welcome anytime,
you only have 2 hot legs, so that's all you hook up to the motor.
the 3rd motor wire will have no other external connections to the other 2 motor wires
3 phase electricity is somewhat different than automotive electricity, but all of the same laws apply regardless of AC current or DC current flowing
if you worked on Ford electrical systems, you undoubtedly have the mental capacity to grasp anything you need to know about 3 phase power, with a little study
here is a start....

i'm more than happy to try to answer any questions you may have in regards to learning about what you don't understand :)
 
Thanks for reply..have wired two hot off 220 line at junction box to two motor leads.spun motor with my dc motor on my band saw..grinder runs...but kinda slow..like maybe 1/4-1/3 speed..runs same direction forward or reverse..maybe cause turning same direction with band saw motor?.motor not getting hot.is grinder motor 440v??if so how can I speed up rpm..thanks for info on 3 phase site..will study tonight
 
the grinder may be wired for 440/460 :(
if you spun it up with another motor and the grinder did not take off, with single phase applied-
sad to say, you either have a faulty motor or it is not operating at the correct voltage :(
the good news is that you can step 230 up to 460 with transformers , and make use of a VFD- but the VFD is not necessary
the bad news is that there is not really a dirt cheap method of making 460v 3 phase, that i am aware of

if you have access to any capacitors over 50 uf, you could make a static converter to test the motor that's already in the grinder- it won't produce 460v
 
you could also test the motor leads to see if there is fault in the motor.
using an ohm meter,
test motor leads to the frame of the grinder, there should be no continuity
test motor leads by holding the meter lead on a motor wire, then to another motor wire, the should be low resistance shown on the meter- record findings
move one test lead to the 3 rd motor wire and note the ohm reading, there should be low resistance, record findings
now you can move the first test lead to the 2nd wire position and observe the meter reading, low resistance should be indicated, record findings
if you observe the recorded the readings, they should be very close if not equal in resistance for a 3 phase motor in top operating condition
 
If all else fails, find you a electric motor shop and take the motor assembly there. They can quickly check and test the motor and see what voltage is required for the motor and if it is shorted out. They can also rewire the motor for the voltage needed if you wanted them to do so. It will always be a 3ph motor it cannot be changed to a 1ph motor.
 
All three ohm out at 47--47.5..motor runs smooth.not getting hot..runs slow to me..if I added the third leg it would run higher rpm? Thanks for reply.
 
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