Thanks for your reply.
we have to do a copper loss test on the winding of a linear induction motor. The VA required to do energize to full load current at 60Hz is too high. If we run the test at 25 cycles the test voltage will be lower for the same current. We would use DC but not enough...
Hi. Can anyone shed some light on how power factor of a system is affected by a VFD operating a motor under low load? The stator will be energized to full load amps with no rotor.
Is the power factor improved drastically due to the use of the drive?
thanks
Thanks
The GGP51A is different from the 53A or 53C, both manuals of which are readily available. 51A has different connections. I would call GE but they are acompeditor and would not likely supply it without a truckload of free beer...
Oh, if only that were the cost.
Hi
We have a small situation where we are in a plant and there is no documentation or even site schematics. Does anyone know where I can get a copy of a relay manual for a GE GGP51A, the manual number according to GE website is GEI 16377. It is a reverse power relay in this case used for...
JohnHamburger is correct, you want to see response in load reaction including full load rejection, these are very importantfor complete units. Also, you may also request a "surge test" if the results of this normally factory provided test are not available. Especially since the...
Be aware also that any component of unbalance will contribute to rotor heating and may be an argument for upsizing the genset to accommodate this. If the genset is closely matched to the total available maximum load the rotor and field may sustain damage from heating while the KW rating is...
wbd is correct, you should consider the ratio of gasses rather than one gas alone. There is a tried and true method called Rogers Ratio which is a simplified math model to indicate what the problems may be. Arcing from tap changer or lead is more likely with acetylene.
Bru
yamin
you have chosen wisely. I personally reserve patches for equipment near the end of service life, not the beginning. I am sorry to hear that you must encur the expense but it is really for the best.
Some links, http://www.specseals.com/index.htm
Read about it at...
prc
The dew point of the oil would be valuable only to check that the oil being pushed into the unit is still dry after being in storage outside the transformer tank. If the oil shows a moisture content higher than 10-12 ppm higher than what came out of the Tx tank originally, you could have...
prc..
Dew point can be taken in oil. The probe is designed for it and moisture is derrived from temp and dew point.
I am not familiar with the cloud chamber type. It is simply a probe with matched transducer unit (they are sold together as one unit) and require care in handling but are...
Sorry, just a bit more...
These items are not specifically hard to get in north america and you will simply have to add the logistics of getting to the remote areas to thier deliviery. Most of these units are in the posession of utility people and can often be borrowed. I have had good...
prc
Hastings makes some good vacuum probes, or a simple monometer will do. (this is often the best anyway). You can view their stuff at http://www.hastings-inst.com/
For dew point, Panametrics in Ireland are well trusted in utility circles. View their stuff at http://www.panametrics.com/
It...
A lot of good hints.
I have repaired many of these.
Here is what I would do if it were my unit.....
Drain the oil, while you fill the Tx with DRY (-55C) air if available. (Maintain positive air pressure) Replace all the gaskets with mild positive air flowing thru windings (still use -55C...
gordonl
I know that there is no differentiation between ground fault sensing and phase imbalance with this kind of (residual ground) connection.
also, stevenal, you can test the relay using a single phase set with either configuration without changing settings. If the current injection is...
