I have been asked to find a 1:15 gearbox that can step up the rotation of a 10 KW / ~120 rpm input shaft with an output of a 10 KW / ~1750 rpm 4 pole generator. It's for a small wind turbine.
I have found 15:1 helical and double helical gear reduction units. Can the input/output be changed...
I agree that there is no problem with elf and the human body. I, myself, have been frequently subjected to strong electromagnetic fields for years with no harmful effects. Maybe this issue will subside in this office. Thanks for all the comments.
Phil
I have been asked to investigate an ELF occurance. Several offices in the building are located above a 3 phase 460 volt transformer. Their computer screens flicker intermittenly during the day. The highest reading I got was 85 Gauss on a Extech 480823 electromagnetic field meter.
I have not...
Hi Allodola,
I have also delt with ASAP. They are very helpful and their original Kohler parts are cheaper than the dealers.
Instead of using an overvoltage relay, could you use an MOV? www.digikey.com has them for cheap.
Allodola, I disconnected the kill switches for the external engine circuits. I think they all short to ground. Might be the case. I'll hook up one at a time and see what happens.
Yes, the VR is new and so is the bridge rectifier diode that's connected to F1 & F2.(far side of the pics mounted to the wall.)
The relays in the foreground are not new. They seem to function correctly. I've switched their positions without any change in voltage.
Allodola, a few pics of the dirty boards are listed in a url earlier in this post. :) You can see if that's what you need. If it is, I'll figure out how to post the clean ones.
warcross, I understand the zig-zag. How is the double delta wired? What are the advantages of double delta vs...
Hello Allodola,
I now have a manual coming from Kohler. It probably does not show the board schematics. I have a few pics of the cleaned board that shows every part except one chip. If you need them, let me know. They are ~1.5 mb each.
What's your ohms reading across the sliprings and power...
I think I may have found the problem, or at least one. V7 and V8 wires, which are from the generator powers the AVR. Both are putting out intermittant voltage readings. Looks like it's time to take the generator apart and look.
This is going to take a few days.
Thank all for the comments! This...
"The rotating field has four poles." This has 27 ohms across the slip rings without brushes.
"We usually call the stator windings on your type of genset the main windings or the power windings." The main windings are 0.9 ohms. 12 wire main winding.
Sorry for the confusion.
The field resistance was measured at 0.9 ohms by checking the start and end of each winding after the leads were disconnected from each other.
The resistance measured through the slip rings, with the brushes and holders removed, was 27 ohms. I will check the voltage between each lead today.
My...
waross, the 27 ohms were from the sliprings. Sorry, I should have made it clearer. No continuity between the slip rings and the rotor shaft or to the case.
The new voltage regulator and AVR board are from Kohler.
Here's a link with pics of the electronics...
I purchased a new AVR and voltage regulator. No change in the output voltage, even with the waffle iron.
The rotor checked out at 27 ohms. My book for single phase unit shows the reading should be between 2.5 and 4.5 ohms. This sounds too low. I'm guessing it should be the same for three phase...
Are you refering to a capacitor/inductor resonation? Can't find a cap anywhere except on a VR board in the unit.
"If that is so you may be able to provide some 'manual' field current and see the output rise."
I'm not sure exactly what you mean. 12 volt battery flash to the field windings and...
I connected a 13 ohm nichrome resistor across 1 leg to neutral. Same thing as before, 30 Vrms, 64.4 Hz. Scoped out as a good sine wave.
Could this be a voltage regulator problem? Does the rotor need to be flashed with higher voltage?
Again, any help/advice is very much appreciated!
I'm new to the forum.
I have a Kohler 15RMY62 208V 3 phase 15 KW generator that is producing 30 VAC (rms) at 1800 rpm.
The diodes and brushes have been replaced.
I disconnected the field windings from each other and they are 0.9 ohms each. The wiring has no visible signs of burning or...