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Converting 110 volt to 220 v (single phase) with transformer .... ok idea ?
All this verbiage over a simple problem. Transformers do care what frequency they are run at because the cycle time determines the time the flux has to approach saturation. The other factor determining the degree of saturation is voltage. You can run a 50 cycle transformer at 60 cycles at the...- 9100
- Post #24
- Forum: Transformers, Phase Converters and VFD
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Monarch 10ee retrofit
DC motors do break down occasionally. I had one that extended the boom on one of Gannet's trucks. Running on 24 volts, it was wound with copper ribbon from a commutator bar through one slot, back through another and to a bar. The next coil went from the next bar to the same slot, so there were...- 9100
- Post #32
- Forum: Monarch Lathes
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Monarch 10ee retrofit
The insulation on one of these DC motors is made to withstand a couple hundred volts from either lead to ground. If you float the DC with ground being the midpoint, you should have no worries from that quarter. One caveat is that the armature is wound with wire that can only stand a few amps...- 9100
- Post #31
- Forum: Monarch Lathes
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Help engineering a basic vacuum reservoir.
As is so often the case in these inquiries, the size and shape as well as the pressure (negative re atmosphere) is necessary to make any sort of reasonable estimate. In a sense, there is no such thing as a vacuum, only a pressure lower than 14.7 PSI absolute. The sort of vacuum that powers your... -
Saving the 5HP Kinamatic DC Motor
I have worked on lots of them, beginning in 1951 when I got a summer job in the P. E. Chapman Electrical Works at 1820 Choteau in St. Louis. I got a basic education, really basic. Penrose Embry "Pappy" Chapman was a crazy old coot, but a smart and extremely penurious one. Their product was...- 9100
- Post #30
- Forum: Monarch Lathes
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Saving the 5HP Kinamatic DC Motor
The armature has more commutator bars than slots, so it has some form of multiplex winding, which is used to give more smaller increments to torque. If convenient, see if the brushes are exactly 180 degrees apart or shifted half of one commutator bar from each other. That is the difference...- 9100
- Post #23
- Forum: Monarch Lathes
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Transformer question
If you have an open 0 point, you will have 370 open circuit volts to ground, but as soon as the motor draws current, the inductance of the transformer will reduce the voltage so there is no problem. Bill- 9100
- Post #7
- Forum: Transformers, Phase Converters and VFD
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OT-Has anyone made an automatic brick laying machine?
Looking at a tall brick building and contemplating working on one way up in the air, I wondered if anyone had automated the process. It doesn't seem like it would be too hard to do. Of course, the unions would put a contract on you. Bill -
Transformer question
I have no idea what your code says, but I think that the fuse in the 380 line would give reasonable protection to the other two. Typically, instruments that might have a half dozen voltages from one transformer only fuse the incoming line because a short on any of them translates to overcurrent...- 9100
- Post #4
- Forum: Transformers, Phase Converters and VFD
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Transformer question
It depends on how much current total the items use. What you propose certainly will work if there is enough capacity, but a 100 VA transformer is not very big. You would use about a 1/3 amp fuse in the 380 line. Bill- 9100
- Post #2
- Forum: Transformers, Phase Converters and VFD
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Need help wiring and reversing motor
Just what I need. I have had to calibrate a couple of digital panel meters on VFDs to read in RPM. First I had to calibrate my strobe light, get the speed adjusted to an even number and then adjust a pot to make the meter read right. Winding my career down as I am, I am not going to spend... -
Need help wiring and reversing motor
I haven't been watching the thread in the past. [I] looked at the opening and scrolled down to the pictures, and saw the connections. I should have read more instead of just glancing at the many posts, but didn't, so I did not see that you had managed the reversal. Re changing the voltage... -
Need help wiring and reversing motor
As always a lot of sturm und drang over a simple problem. In the picture of the connections there are two wires with push on connectors, pink and blue (sort of). reverse them and the motor will start in the other direction. That is all there is to it. Bill -
A question to grinding shops what causes this hub damage
I agree. A friend works in a shop that has a Kent grinder identical to mine. He says the nut holding the hub on the shaft is chewed up, rounded corners, from beating on a wrench. Mine is almost in new condition it came in because I only use hand pressure on the nut and on the stone's nut. To... -
Saving the 5HP Kinamatic DC Motor
My Sheldon came without a motor because it was originally intended to be a demo with a variable drive but they went out of the manual lathe business and soon, all business. I installed a 15 hp DC motor and feed it with a three phase Variac and three transformers that originally powered heaters...- 9100
- Post #17
- Forum: Monarch Lathes
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VFR and Digital RPM meter on drill press, "mysterious" behaviour...cannot find answer
Working with sensitive electronics, I have seen similar effects many times. One of the causes is having a common ground for a sensor and something that generates spikes. You can build up an amazing voltage on a ground wire, just from its resistance and inductance. People would ask what were the... -
RPC phase loss protection
Place three posts in the ground at the points of an equilateral triangle with two on a horizontal line and one above the center of that line at the altitude of the triangle. Stand at the center of the horizontal line and observe the three points. Two will be 180 degrees apart and the third one...- 9100
- Post #15
- Forum: Transformers, Phase Converters and VFD
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Strike One MariTool
I have repeated the story as accurately as I could, told to me in the first person by the victim. He was generally pretty honest but I think not above adjusting a tale a bit. In any case, it hardly will affect our fates. Bill -
Strike One MariTool
A company I worked for had a holiday and overtime pay policy that to get it you had to clock in on or before starting time and clock out on or after quitting time. One labor day a co-worker went to a rural area and on his way back saw a deer hit by a car. The driver didn't stop and the severely...