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Kohler wiring diagram help

HooDooBuilds

Registered
hey I've called kohler, and Loftin equipment in PHX, a few times with my model # 60R0Z74, Spec # 80527A5, serial # 077204 and they have not been able to tell me anything about my generator. I just picked this unit up and it has been sitting for a few years at least, only reads 218 hrs. my issue is I'm getting 0 volts and 0 amps while running. I'm trying to get my hands on a wiring diagram so I can make sure the unit is hooked up correctly. Any information, manuals, or wiring diagrams would be greatly appreciated. from the information I found on this forum, in regards to serial # and dates, it would seem this generator is from 1942. I know that is incorrect. I'm also baffled by the serial # on the tag is printed instead of stamped into the metal.IMG_1627.jpeg60460381857__D6281281-B3C2-4BC8-BF1F-9739DAC73AD4.jpegIMG_1610.jpeg
 

Zephyr7

Registered
That doesn’t look like a 1940s vintage genset to me. Probably 1970s or 1980s, before they changed to the current “Kohler tan” color. You have the “Kohler gold” color.

Check inside the generator end housing and see if there is a connection diagram in there for the generator end. If you don’t have that, I can send you one — or look through my old posts since I’ve posted it before.

Connection stuff is usually pretty easy. Start is on terminals 3 and 4 in the control board, usually on a 4 position terminal strip. Power comes off the line side breaker, which should be the biggest breaker on the unit with a rating slightly above the rated output current of the genset.

Bill
 
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LWB250

Registered
I can clear this up for you somewhat.

It's an early FR-I set, or Fast-Response 1 from the early to mid 1980s. It's city water cooled which was an engineered special, meaning it wasn't a standard product, it was a one-off built to order. That's why you have an 80xxx spec number. The spec number, which is critical to identifying the build ticket and all the parts used on the unit, means nothing to Loftin because the only place there's information on it is at Kohler on microfilm. Sadly, Loftin has been around (they're a legacy Kohler distributor) long enough they should recognize an engineered special spec number.

Serial numbers were always on a clear mylar sticker that was placed on the build ticket. After final test and QC the sticker would be placed on the nameplate.

Anyway, since it's an engineered special all bets are off as far as standard equipment. It *probably* has a standard 12 lead FR-1 alternator, which, if it's not working, is a Bad Thing. It's highly unlikely anything but a voltage regulator is still available for one of these, and probably not even that.

Without more pictures I can't tell you anything else. Looks like it might have a non-standard controller, too. A model like this would have had an early DEC-III controller with a lower tray, but from what I can see your meter box is one piece. That means it's possibly a relay controller, which would be a blessing.

Take the sheet metal covers off the alternator housing and take some pictures, especially of the generator end. A straight-on picture of the controller would be helpful as well.

Dan
 

HooDooBuilds

Registered
thank you both very much! It came from a water municipality out of Minnesota I believe. It was their back up power to keep the pumps running. I will take some better photos in the morning and post them. it came with a Zenith transfer switch that wasn't planning on using. I just need the power to run a machine in my shop. I am rebuilding a 52" TimeSaver power. let sander at the moment and that beast has a 40 hp motor on it which requires 53 amps 480 3 phase. hopefully I can get some power running through these cables so I can finally fire up my machine!
 

LWB250

Registered
40 HP on a 60kW genset? I wouldn't hold my breath. What's the code letter on the sander's motor?

The 53 amps is running current, *not* starting current. It's probably a code G, which is close to 6kVA/HP locked rotor.
 

HooDooBuilds

Registered
I asked TimeSaver that question and they told me it was the starting amps. I wouldn't be surprised if they were incorrect. could I wire in a slow start to keep the starting amps as low as possible? I'm by no means an electrician, just trying to speed up up build process. really just swinging in the dark here
 

Zephyr7

Registered
I would not count on that genset starting a 40HP motor!

Here’s a better idea: get a VFD (variable frequency drive) for that 40HP motor. Used ones aren’t terribly expensive. Some VFDs will let you run a 3 phase motor on single phase, but I doubt it for a motor that big. What a VFD will do is allow you to ramp the speed of the motor up over a few seconds to make it “soft start”, which will DRASTICALLY reduce the startup current needs and almost certainly let you run the motor with your genset. You’ll also get variable speed ability and a lot of other nifty motor magic when using a VFD.

Bill
 

HooDooBuilds

Registered
The motor code is G.
Bill- I was looking into VFD and rotary phase converters when I was looking at using single phase to power this up but I wasn’t able to get a power upgrade from my service provider. Hence the genset. Is there any place in particular you could recommend looking for a used one? I wish I would have found this forum a couple months ago!
 

HooDooBuilds

Registered
I’m okay with a little smoke. The machine will always be started with no load on it. Gotta get it up to speed before I can put anything through it anyways
 

Zephyr7

Registered
I’ve found motor drives (VFDs) on eBay before. I like the ABB ones, but they are tricky to setup (many, many options). There are lots of others. Note that sometimes these are called “VSD”s, or just “motor drives”. Just don’t get a “motor center” or a simple motor starter.

If you don’t have any luck there, PM me and I can put you in touch with one of my used electrical supply houses that should be able to find you one.

Bill
 

Zephyr7

Registered
If the motor can be started without load the generator will start it. Oh sure, the voltage will droop considerably, and the engine speed will drop and she'll chug some black smoke, but the motor will start without harm to anything.

https://www.smokstak.com/forum/threads/applying-generator-sets-to-motor-loads.157472/
That’s not 100% guaranteed to work. Been there, tried that. Might work with the motor TOTALLY unloaded (like the motor alone just spinning it’s own shaft), but a big connected rotating mass is often enough to mess things up. Don’t even think of trying it with a compressor.

Personally, I’d go the VFD route.

BTW, for the OP, if you have three phase service on the primary (High voltage lines on the top of the pole that run the transformers), then the utility should be able to provide you with three phase service BUT they will likely charge you to do that upgrade for a residence. If they do NOT have a three phase primary near you, then they won’t want to put in the upgrade or they’ll want a LOT of money (five or six figure) to do it. Ask to talk to your local service planner and ask them, don’t ask the regular sales people.

Bill
 

Vanman

Subscriber
Last Subscription Date
07/10/2019
Well, if it doesn’t work, it will merely manifest as a tripped breaker. I’d try it, see how it goes, and if it is unsatisfactory then I’d explore other options. It would be pretty easy (and fun!) to set up a simple autotransformer starter. Depending on the motor, might be able to set up a part winding start. Lots of fairly simple techniques available if variable speed is not required. I’d imagine that a 40 hp VFD is a pretty spendy piece of kit! ;)

Keith
 

Zephyr7

Registered
I bet you can find a used 40HP VFD for under $1k.

I like your transformer idea though. A few contactors and some beefy control transformers and you can rig it up. Might be able to make your own delta-wye starter even more easily if you want to try that.

Note that the transformers in a starter can be undersized for the load since they are only in circuit for a few seconds before they get cut out by the contactors. Too-small transformers will actually help to limit starting current even more due to saturation effects too.

Bill
 

HooDooBuilds

Registered
I can clear this up for you somewhat.

It's an early FR-I set, or Fast-Response 1 from the early to mid 1980s. It's city water cooled which was an engineered special, meaning it wasn't a standard product, it was a one-off built to order. That's why you have an 80xxx spec number. The spec number, which is critical to identifying the build ticket and all the parts used on the unit, means nothing to Loftin because the only place there's information on it is at Kohler on microfilm. Sadly, Loftin has been around (they're a legacy Kohler distributor) long enough they should recognize an engineered special spec number.

Serial numbers were always on a clear mylar sticker that was placed on the build ticket. After final test and QC the sticker would be placed on the nameplate.

Anyway, since it's an engineered special all bets are off as far as standard equipment. It *probably* has a standard 12 lead FR-1 alternator, which, if it's not working, is a Bad Thing. It's highly unlikely anything but a voltage regulator is still available for one of these, and probably not even that.

Without more pictures I can't tell you anything else. Looks like it might have a non-standard controller, too. A model like this would have had an early DEC-III controller with a lower tray, but from what I can see your meter box is one piece. That means it's possibly a relay controller, which would be a blessing.

Take the sheet metal covers off the alternator housing and take some pictures, especially of the generator end. A straight-on picture of the controller would be helpful as well.

Dan
Hopefully these photos will help out. I found this paper in the control box.AFFEA3BC-53D9-49BF-8B58-5057CD4EF790.jpeg
6EC21267-6DCC-453A-B768-7AB90CD1FDB2.jpegC68D073E-129E-48A6-AF0A-5BDBF333BBA1.jpegA06FB726-A7B6-44F4-A4B2-A1DF1244694D.jpegA110FECB-D7EF-48DD-851B-072F4C72CBD2.jpegBD07BFAC-B442-4580-8D32-FF2EF035CFED.jpeg
 

LWB250

Registered
OK, so here's the dirt:

Paper is for the Barber-Coleman electronic governor, which I presume is located inside the controller/meter box. The controller is not the original one, which is a Good Thing, as the original controller, a DEC-I or "Decision Maker" controller, was a major POS.

This being said, from the looks of the pictures the thing has been savaged by the retrofit. That junction box looks like a real nightmare.

This is definitely an FR-1 alternator. You can do a quick diagnostic by simply firing the engine up with the little three pole breaker ("safeguard breaker") on the side of the junction box closed and the rear cover off the generator and ambient light should cause the alternator to go full field. If not, carefully remove that blue circuit board on the back end of the generator, secure it out of the way of any rotating components, get a flashlight, and with the engine running as described previously shine the flashlight on the end of the rotor shaft where there is a phototransistor located (it's obvious with the blue circuit board out of the way.)

Again, the alternator output should spike. We're talking full field voltage, like the voltmeter will peg. If not, you've got some serious repairs to do.

If output voltage does spike, immediately remove the light source and shut the unit down. You've got issues elsewhere, possibly a bad LED on the blue board or a bad voltage regulator.

Get the flashlight test done and report back. Until that's accomplished there's not a lot anyone can tell you.
 
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Zephyr7

Registered
Some (3) of the phase conductors in the upper left look like they are abraded in one spot. You should check that, maybe put some tape.

The common winding connections look like they are only taped. That is bad. You are supposed to use the thicker butyl rubber spice tape, then cover the splice tape with friction tape, although good quality “regular” electrical tape works well too with at least three wraps over the splice tape. The connections don’t look fat enough to have the butyl tape layer that they are supposed to have.

I agree with Dan that it looks like a wiring nightmare in there. Be careful if you do any work. Let us know the results of your flashlight test.

Bill
 
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HooDooBuilds

Registered
When you say the “voltmeter will peg,” are you talking about the readout on my controller or should I be using a handheld meter somewhere?
 

Zephyr7

Registered
When you say the “voltmeter will peg,” are you talking about the readout on my controller or should I be using a handheld meter somewhere?
The controller meter will peg. “Full field” output voltage with no load is the maximum voltage the generator is capable of producing under any condition. Normally the voltage regulator increases the field current with increasing load to keep the output voltage constant. Without the regulator, the output voltage would drop with increasing load due to resistance in the generator windings.

With no load on the generator and full field, a “120 volt” generator may put out 160-180 volts or so. A meter with a 150 volt full-scale reading will “peg” and read over full scale with full-field no load generator voltage.

A seperate meter should just read whatever voltage the generator end actually produces during this test, which is a good thing to measure and know, so I’d recommend using a separate meter during the test just to see how high the output voltage goes.

Bill
 

HooDooBuilds

Registered
So I was able to get a reading of 508 volts on the controller with the blue circuit board removed and a flashlight on the end. The connections to the LED were pretty corroded. I tried to clean them up but no luck. Can I get a replacement board or can I just solder in a new LED? Thanks again everyone for all the help! It sure was nice seeing some voltage come out of this thing.
 
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