Fernando,
The motor may be just fine. Multispeed motors may exhibit higher no load current in low speed than high speed due to high magnetizing current required by the low speed connection.
Hello All,
An interesting idea was raised today by my colleague. Let's say you have 3 phase, 2 speed (3600/1800 RPM) consequent winding motor and you're running it at no load at 3600 RPM. Shut the power off, reconnect for the lower speed and energize. At point of energizing the low speed...
kien123,
If you'd like to find out more about what happens to a DC motor when field is removed and armature circuit is powered, take a look at thread181-27567 .
I think in a back-to-back test with 2 induction motors, the two motors are coupled together through a gear box. One motor runs at rated speed, the gearbox is adjusted so that the second motor (which will be generating power) runs at the same exact speed. I believe at that point a switch is...
I went ahead and contacted EASA. They also suggested Schulz Electric. Schulz Electric can't sustain the load of a 1000+ HP motor for an extended period of time. We also can't test the motor back to back as we won't have another motor of similar rating available to do a back to back load test...
Hello all,
I've been doing a bit of a search online for companies that deal with testing motors in north east US. In particular, I'm looking for a place that can test (heat run) 1000+ HP @ 3600 RPM continuous. So far, several places that I found have the power required but can't sustain...
Often when testing for motor efficiency we use a torque tranducer between the motor and the generator to measure power output (torque and speed) at the motor's shaft. However, the transducer's can get a bit pricy.
Sometimes your power supply may also cause 2x line frequency problems. Whether it's harmonics or line unbalance as the cause, we've seen 120Hz (US) at high levels before. Often going on motor-generator set seems to reduce the 120Hz level.
In a delta connected transformer, each line is connected to two transformer phases. Thus, each phase current is equal to Iline/sqrt3. <br>You can also find out the phase current by using VAphase/Ephase
Polarization index is still used to check condition of motor winding insulation. The capacitive charging current usually decays to a negligible value before the first measurement at 1 minute is taken. There is also absorption current that's present. However, this also decreases to nearly...
It struck me as being a bit strange when another engineer suggested the use of silver brazing with aluminum. I didn't check the actual melting points of the alloys but I know that Aluminum melts at approximately 660 C while Silver melts at about 1080 C. So it didn't appear correct to me that...
