Bridgeport motor ID

LEEQ said:
Not too clear on the amp thing. I have an amp setting on my digital meter. I don't however know where to stick the probes to test amperage.
Click to expand...
AMP readings are taken with the amp meter as part of the circuit if you don't have a clamp on type meter.
another way of saying it would be to disconnect 1 power wire from the motor put one lead of the amp meter on the power wire (black) and make secure so the test lead wont slip off, then take the other test lead and hook it to the motor wire you had just removed
the power wire from(1,7 pairing), making the meter part of the circuit to test amp draw. i would test 2 different power legs in this way
black to 1,7 pairing, then white to 3,9 pairing.
does this make sense to you?
let me know i'll try to explain better if not.... my concern is for your safety you will have wires exposed, please turn off the circuit when working on it:))
mike:))

i'll be out to dinner until later on, but i'll be happy to answer any questions when i return home!
 
I understand the method now. You were very clear. I also take my sweet a$$ time about fooling with electricity. I'm just unfamiliar with both three phase and motors. After reading and you guys' help, I feel very confident. I just got home from a wedding, but before I did I wired up bport except the breaker to power it up. Hated having to go that wedding, excited about tomorrow am though. With any kind of luck it will fire off so I can get some readings, and the head I put together doesn't have an earth shattering kaboom.
 
Leeq,
if you do come across any issues, i should be around the house for most of the day tomorrow.
i'll check in to see your progress periodically.
we'll get you zero'd in soon!
just another point, you may not want to put the belt on the motor for testing purposes. it won't hurt if you do but it will make hunting down strange motor noises easier if there is any fault in the motor. keep in mind though the motor pulley will continue to spin for a while after you kill the power to the motor, there is only mechanical resistance that is going to slow the motor. if you are careful you can use a chunck of wood or plastic to gently slow the pulley.
mike:))
 
Ok, no earth shattering kaboom. Hard to believe that the motor turns like that at 2/3 hp, wow. For voltage testing, between1,7 and 2,8 I got 208v. Between 3,9 and 2,8 I got 200v. Between 1,7 and 3,9 I got 240v. As far as amps, not such good luck. I secured one meter lead to 1,7 pair and the other to leg A that feeds pair 1,7. Now the meter is in between pair and leg A. I turned on the breaker, turned on the switch and nothing. I reversed the switch and got a hum. Motor doesn't turn and meter didn't read anything. Does all that mean anything to you?
 
Are you running it off of the static phase controller and trying to determine what the horsepower of the motor is? If so, I don't think that is something you can measure correctly that way.
If you absolutely can't live without knowing the horsepower then maybe put an ad on CL asking for someone with a rotary phase controller (which theoretically provides 100% 3-phase power) or a shop with real 3-phase power and see what they'd charge for 10 minutes of their time for you to take the motor to them to power it up at 100% and then measure the amps drawn the way explained above.

If you're going to keep fiddling around with it in your shop though, are you measuring like this:

power panel wired somehow (directly or through plug) to the static phase controller.
static phase controller has three wires coming out to those three paired wires on the motor.
two of the wires go directly to the motor.
one of the wires gets connected to one of the wires on your multimeter and the other wire on the multimeter goes to the motor.

And of course to make sure you don't burn out, blow up or destroy your meter/self/shop: there should be a setting on your multimeter to measure amps instead of voltage. You gotta set it to the amps, and you have to choose a max amperage higher than you can expect to hit with that motor.

Good luck.
Be Safe.

Joe
 
LEEQ said:
Ok, no earth shattering kaboom. Hard to believe that the motor turns like that at 2/3 hp, wow. For voltage testing, between1,7 and 2,8 I got 208v. Between 3,9 and 2,8 I got 200v. Between 1,7 and 3,9 I got 240v. As far as amps, not such good luck. I secured one meter lead to 1,7 pair and the other to leg A that feeds pair 1,7. Now the meter is in between pair and leg A. I turned on the breaker, turned on the switch and nothing. I reversed the switch and got a hum. Motor doesn't turn and meter didn't read anything. Does all that mean anything to you?
Click to expand...

through osmosis we know..... you have 240 volt supply voltage, good!
1&7 has 1 power wire on it(your A or B), the 3,9 has the other power wire (you other A or B). i'm not sure how you have them
just for argument, i'll assign the color red to A, and the color black i'll assign aw sire B, so to recap....
1,7 connects to wire A, 3,9 connects to wire B between these legs you got 240, right? good! these are the the legs we will derive our hp reading from as soon as we can get our amp reading.
the hum you got was the motor "single phasing", there were not three legs available to to start the motor.
this probably means that your meter either wasn't set to read amps, or the fuse in your meter has failed, or possibly your meter may not function correctly, as the leg you are amp testing was not completing the circuit through the meter, make sense?
we can ascertain you motor's hp with a high degree of accuracy with the last part of the equation, the amp reading, as soon as we can get a good reading, i'll get you zero'd in
mike:))
 
when all else fails read directions? I'm going to dig up my meter manual and see if I did something wrong there. It seems pretty straight forward though. I'll test again then and see if I get better results. fingers crossed.
 
LEEQ said:
when all else fails read directions? I'm going to dig up my meter manual and see if I did something wrong there. It seems pretty straight forward though. I'll test again then and see if I get better results. fingers crossed.
Click to expand...

i just went out in the garage and was messing around with taking the readings on a 2HP 3 phase motor that runs from a RPC in the shop.
my radio shack digital 10Amp max amp meter, it appears the impedance inside the meter is causing the issue just like you had, a buzz no start. i didn't consider that issue as the digital amp meter i use normally has a clamp on amp probe and doesn't have to be wired in.
i then took a panel amp gauge i had laying around wired the meter in series and re-preformed the testing with a result of an amp draw of 5.8 Amps as expected.
it looks like if you are dead set in finding the HP, you're going to need either to borrow or buy either a hand held analog amp meter you can wire into the circuit or you'll need to buy or borrow a clamp on type meter.
HF, home depot, lowes, ace hardware, radio shack, usually have relatively inexpensive clamp on meters or inexpensive analog meters
they'll may make the job easier. a panel mounted meter would suffice as well provided it is made for AC current.
mike:))
 
not to beat a dead horse, but let's take a look at the equation i gave you earlier
Watts(P)= Volts X Amps
Watts/746= relative hp

my 2hp motor that i tested in my last post went like this....
my supply is 243 volts at time of testing. amp draw was 5.8 amps
P= 243 X 5.8
P=1409.4

Hp= 1409.4/746
HP=1.8892761 actual hp running on an RPC circuit
mike:))
 
our meters read 10a DC! NOT ac. I looked here local and didn't find anything. might have to go to lowes/hd/menards and get something that will read ac amps.
 
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