300 KW Delco AC Generator E7080 automatic voltage regulator recommendation?

[forhire]

I need to hook up an old 300 KW Delco AC Generator E7080. The exciter wires, F+ and F- are not hooked up to anything. They were cut off along with a bunch of wires in the conduit when it was pulled from service. It appears I'm missing the automatic voltage regulator. Can anyone point me in the direction of a reasonable AVR for this generator?

It has a Woodward ESSE-2 speed switch with a magnetic pickup but looking at the manual this just appears to only handle over/under speed protection.

I'm still tracing out wires. As typical I have no complete schematic.

Any thoughts on what is needed to make this unit make power? Besides a good power wash.

[smithdoor]

The exciter is 1 amp 100 volts DC.
Simple to come by just find a AC generator 110 volts and put rectified on ac generator and adjust voltage to 100 volts DC.

Dave

I need to hook up an old 300 KW Delco AC Generator E7080. The exciter wires, F+ and F- are not hooked up to anything. They were cut off along with a bunch of wires in the conduit when it was pulled from service. It appears I'm missing the automatic voltage regulator. Can anyone point me in the direction of a reasonable AVR for this generator?

It has a Woodward ESSE-2 speed switch with a magnetic pickup but looking at the manual this just appears to only handle over/under speed protection.

I'm still tracing out wires. As typical I have no complete schematic.

Any thoughts on what is needed to make this unit make power? Besides a good power wash.

[forhire]

The exciter is 1 amp 100 volts DC.
Simple to come by just find a AC generator 110 volts and put rectified on ac generator and adjust voltage to 100 volts DC.

Good thought for testing it. I'm pretty sure it can be shunt/self excited with the proper AVR. I still need to figure out the what drives the governor actuator. I didn't spend much time on Saturday. This unit is replacing a tired unit so I may be able to use the AVR system off the old generator. I'll check the other machine tomorrow.

[smithdoor]

I had 25kw generator the exciter was missing it was 32 volt DC. I found a truck alternator that 24 volts work great

Dave

Good thought for testing it. I'm pretty sure it can be shunt/self excited with the proper AVR. I still need to figure out the what drives the governor actuator. I didn't spend much time on Saturday. This unit is replacing a tired unit so I may be able to use the AVR system off the old generator. I'll check the other machine tomorrow.

[forhire]

I'm thinking something like the Power-Tronic XR8 would work.

https://power-tronics.com/master-cat...anuals/XR8.pdf

[forhire]

I had 25kw generator the exciter was missing it was 32 volt DC. I found a truck alternator that 24 volts work great

Interesting. This machine has a belt driven generator. I had assumed it was just used for battery maintenance. Maybe I should check the output.

In any case I should be able to put 24V from the battery to the exciter winding and measure some power output.

[smithdoor]

The belt drive is for the exciter.

Dave

Interesting. This machine has a belt driven generator. I had assumed it was just used for battery maintenance. Maybe I should check the output.

In any case I should be able to put 24V from the battery to the exciter winding and measure some power output.

[forhire]

The belt drive is for the exciter.

Here a picture of the generator. Maybe someone can recognize it. Any marking have long been painted over. I'll need to bring out a mirror to see if it has two sets of brushes. I'm thinking it possibly outputs 24V and 100V DC. There appears to be a voltage regulator below it, I'd assume for 24V. I'm having a heck of a time tracing stuff out. A lot of wires change colors inside the loom. I need to bring out my number book and start labeling stuff.

[jpump5]

That is very different from the generators I work on.
(newer,25-100kw). Is mag speed sensor picking up ring gear
teeth on flywheel? Is there some sort of a throttle actuator
(maybe in injector pump) to regulate engine speed/output
frequency?
I’d be careful power washing around cooling air openings in
generator head.

[smithdoor]

The generator is a replace with a 2 belt pulley.

Dave

Here a picture of the generator. Maybe someone can recognize it. Any marking have long been painted over. I'll need to bring out a mirror to see if it has two sets of brushes. I'm thinking it possibly outputs 24V and 100V DC. There appears to be a voltage regulator below it, I'd assume for 24V. I'm having a heck of a time tracing stuff out. A lot of wires change colors inside the loom. I need to bring out my number book and start labeling stuff.

[forhire]

That is very different from the generators I work on. (newer,25-100kw). Is mag speed sensor picking up ring gear teeth on flywheel? Is there some sort of a throttle actuator (maybe in injector pump) to regulate engine speed/output frequency?
I’d be careful power washing around cooling air openings in generator head.

I doubt it will actually get power washed. I have a very short window to swap this out. It has a mag pickup that is used by the over speed switch. The governor is an old mechanical setup. I mistook the air solenoid mechanism as the governor when I originally looked at it. I just need to trace out the exciter power from the from belt driven generator and verify it actually was being used.

The generator is a replace with a 2 belt pulley.

Yeah, I wish I could find a model number of the generator. Knowing my luck it's on the back side. Under the back cover there are some brushes and it looks like a couple more brushes in the side.

They had it running a year ago long enough to verify it wasn't making power. I traced out the air solenoid and fuel solenoids yesterday... not sure how it was running as the fuel solenoid power is in the cut bundle. I suppose it had enough fuel in the lines to power briefly when they tested it. Unless it's normally open which doesn't make much sense. I should have time tomorrow to put fuel and batteries on it and see how it goes. We really should have been working on this before the hay came on.

[12V71]

Most definitely a 12V71 Detroit Diesel engine (seen a few ), Do you have any overall pics? Especially the governor on the front of the blowers and the rear of the accessory drive/flywheel housing? A lot of those older V engines used a hydraulic Woodward driven from the left hand camshaft opening On the rear of the engine with a bunch of linkage to the engine governor speed control lever.
The fuel solenoid valve may have been a safety shutdown since those engines normally use a stop lever on the governor cover to put the unit injectors to "no fuel". It should have an emergency stop that shuts air off to the blowers... Make sure that's in good working condition before your first start attempt. Those engines set the injectors to full fuel at rest, If they sit long enough they can stick wide open. That will tend to frighten the horses. Good luck with it.

[forhire]

Put batteries and fuel on the genset today. Powered right up. Verified the belt drive generator only outputs 24V. It has nothing to do with the field windings. Fuel solenoid must be powered to run. Air solenoid is for overrun shutdown. Verified the generator makes power then excited. Field winding resistance measured 50 Ohms. Spoke with a local generator guy and he confirmed I needed an field winding voltage regulator of some kind. He suggest looking at Basler.

Looking at the other generator I found a Basler VR hidden away. Unfortunately the VR63-4 is only rated for 63V windings continuous. Hookup is very simple.




For a 100V winding it looks like my best option will be a Basler AVC125-10, but unlike the VR63-4, it cannot direct sense current so I'll need a current transformer. I'm now trying to figure out how to size it properly. Of course this will be hooked up double delta so it will be derate by 1/3. The Power-Tronics XR8 direct senses so it may be simpler.

[forhire]

I think a current transformer with a ratio of 1000:5 should work. If I did my math right... 300 kW derated by 1/3 for single phase would max around 925 amps making a 1000A to 5A CT about right. Am I in the ballpark?

[smithdoor]

If you need gauges for generator I have a new set 4 ½" (voltage, Ampage and Frequency)

Dave

I think a current transformer with a ratio of 1000:5 should work. If I did my math right... 300 kW derated by 1/3 for single phase would max around 925 amps making a 1000A to 5A CT about right. Am I in the ballpark?

[forhire]

I ended up picking up the Basler AVC125-10 AVR unit and a 1000:5 current transformer off eBay. Less than $200 bucks shipped. They arrived this morning and I completed the installation this afternoon. It turned out to be very straightforward. I did have to flash the field winding but after that it started making power as expected.

Switching the unit to 240V/120V single phase was a bit different. The unit is a 10 lead wye, it still has 6 winding like a 12 lead, but T10, T11, & T12 form a wye point neutral internally and are only accessible as T0. Typical wye voltages are 208V/120V or 220V/127V. If you want 240V/120V you have to use a bar-diamond connection, sometimes called a Collin's connection. This is my hookup schematic. If you want more details see this thread: https://www.eng-tips.com/viewthread.cfm?qid=344367

Now with the power sorted we need to move the beast, install the stacks, and hook it up to the switchgear.

[forhire]

We swapped the generators the other day and moved the Murphy ASM200 auto start module, oil gauge/sender, and a few other bits from the old genset to the new. We now have it working well in manual mode. I figured I'd post a photo of the exciter module and a little digital voltage/freq gauge we used to dial it in. It's making very stable power even under load. Unfortunately the ASM200 uses dry contacts to signal start and when I traced back to the ATS, which was replaced last year, I discovered it was just an ATS and lacks the controller that normally signals the genset. After a bit of back and forth I learned it has been switched manually for a long time. Now I need to figure out how to signal a Generac ATS, looking at the manual it expects a connection to a Generac motor start module, and is pretty thin on details. It appears it needs a 12V signal from the generator when ready and the generator needs a start signal. I only have one pair to the generator right now so it's kinda a chicken before the egg type of problem. I was really hoping to be done.

[forhire]

I ordered a DATAKOM DKG-175 ATS controller. It should handle everything I need in a single package. Anyone ever use one?
This is the eBay listing: https://www.ebay.com/itm/26485620419...53.m2749.l2649

This has a MCB and GCB contacts which will replace the transfer relay that required 12V from the generator. It also has dry contacts to start the generator. It appears to have all the features one would normally expect.

[forhire]

I wanted to report back and let you know that the DATAKOM DKG-175 is working great. Setup was pretty simple. The unit requires 170V-300V phase to neutral. On split single phase, like we have here in the US, the phase to neutral is 120V, so I hooked it up 240V. I tied R, S, and T together and disabled phase order detection (default). N1 sense is connected to RST and N2 sense to NEUTRAL. The unit then powered and I programmed it for 60Hz, voltage limits, and such. I then hooked up E1 sense and E2 sense to G and NEUTRAL. MCB and GCB where then connected to the contactor A and B coils. And finally the dry contacts to start the generator. The rheostat on the front sets the generator run time before activating GCB, this allows the generator to come up to speed unloaded. Right now I'm changing over in about 7 or 8 seconds.

Mufflers have been installed. One heater is working, waiting for parts on the second. I think all that's left is battery tender. The lights are on but it doesn't appear to be charging.

[forhire]

With the Generac ATS sorted and controlling the generator it's time to sort the second ATS that handles the other half of the farm, an old Cutler-Hammer. For a long time it has had to be manually closed when on generator. It has a MCP229 controller. Right now the only light on it is a flashing red light on EMER. FREQ. which according to the manual means the generator frequency is out of range, which is logical because the generator is off. NORM. VOLT and NORM. FREQ. are both off. The manual suggests the controller is bad. I still need to verify the voltages. Anyone familiar with the MCP229 controller?

[avistar23]

I wanted to report back and let you know that the DATAKOM DKG-175 is working great. Setup was pretty simple. The unit requires 170V-300V phase to neutral. On split single phase, like we have here in the US, the phase to neutral is 120V, so I hooked it up 240V. I tied R, S, and T together and disabled phase order detection (default). N1 sense is connected to RST and N2 sense to NEUTRAL. The unit then powered and I programmed it for 60Hz, voltage limits, and such. I then hooked up E1 sense and E2 sense to G and NEUTRAL. MCB and GCB where then connected to the contactor A and B coils. And finally the dry contacts to start the generator. The rheostat on the front sets the generator run time before activating GCB, this allows the generator to come up to speed unloaded. Right now I'm changing over in about 7 or 8 seconds.

Mufflers have been installed. One heater is working, waiting for parts on the second. I think all that's left is battery tender. The lights are on but it doesn't appear to be charging.

This is very interesting, i have converted several Generac switches alot more barbarically, i work on alot of older gensets and tend to use regulators from MTS in Miami, i think i will revisit my Generac switches and look into the module you used, it looks great, am i correct that you bypassed all the relays in the generac and are using just the module to control the coils on the contactor ? i cant remember if they also have limit switches like kohler switches? Great info glad im not the only one tinkering with old gensets.

[forhire]

This is very interesting, i have converted several Generac switches alot more barbarically, i work on alot of older gensets and tend to use regulators from MTS in Miami, i think i will revisit my Generac switches and look into the module you used, it looks great, am i correct that you bypassed all the relays in the generac and are using just the module to control the coils on the contactor ? i cant remember if they also have limit switches like kohler switches? Great info glad im not the only one tinkering with old gensets.

I had ordered some voltage sensing relays but happened across this module and it was a LOT simpler. This Generac ATS does not have limit switches to bother with on the transfer switch. It's all handled by a DTDP relay so swapping it over was easy. Just need to switch lines 126. and 205. See the attached diagram.

Now, switching over the Cutler-Hammer which is motor actuated with limit switches will require a little more work. I'm likely going to pull the controller and check diodes and such.