| Author | Message | ||
| Henry van de Graaf (Hcvdg) (12.13.226.21)
Rating: |
I'd like to replace the 12 volt alternator on my 4106 with a 24V unit. I called one of the alternator outfits (Kirks) and was told that by replacing the field coil in my 12V unit I could convert it to 24V. Da Books show my alternator to be a Delco-Remy 1117670 and the 24V unit (4109A) to be a 1117692 50DN. Is this a low cost option? Kirks quoted a price of $685.95 + core for the 50DN and about $80 for the field coil. My alternator work fine in the 12V configration (I'd hate to screw it up). Thoughts? | ||
| Gene R. (12.13.175.70)
Rating: N/A |
Henry, you can change the 12 to 24 by changing the field windings. This is usually called a rotor winding when the wire is wound around the moving rotor. In your case, where the winding is stationary, it is called a field winding. The stator will run hotter under high loads in this configuration but then you don't need 250 to 300 amps if you are not running bus air anyway. You should have no problem doing it this way. We do it quite often. Be sure to change your regulator also. Gene R. | ||
| Richard Bowyer (Drivingmisslazy) (65.207.109.44)
Rating: N/A |
Gene, can you please explain something to me about automotive type generators/alternators? Are all automotive ALTERNATORS revolving field design with the output power taken from the stationary winding? The output power consists of a high frequency, three phase signal that is coupled thru a three phase bridge rectifier to produce the DC? Excitation is fed to the revolving field by a set of low current brushes? Are all automotive GENERATORS revolving armature design with the DC taken directly off the revolving armature via high current brushes with the excitation being applied to the fixed stationary winding? No rectifier required? If this is correct, then which element is changed to convert to 24 volt operation? Would it be the rotating element (field) on an alternator and the fixed winding (field) on a generator? Just trying to fix in my mind the difference, if any, of the automotive products as compared to industrial products. Thanks for any help Richard | ||
| Ace (24.28.44.126) Rating: N/A |
Hey Mr Alternator! How's your wife feeling? Ya'll still got the snow up your way? Glad we were able to chat a bit in Arcadia. Since your the reason Susan and I have a bus, not sure if I should have kicked you or hugged you, but after seeing you again, now I know why I didn't hug you! LOL Hey is a Leece Neville alt any good? I think it is 105 amp alt. How much are they worth? I know you can probably build one for around 60 or 70 bucks but I just wanted an honest answer and I knew you would be the one for that... I think!  Later! | ||
| Steven Gibbs (12.148.43.7)
Rating: N/A |
On the subject of alternators; I am setting up my new IP and from CIP and need to set the tach. I need to know how many poles are in my 50DN direct drive on my 8V71 in my 1984 MCI MC9. Any help will be appreciated. Thanks, Steve | ||
| Gene R (12.13.175.89)
Rating: N/A |
Richard,You answered you own questions!!! Here are a few other related things. In changing a GENERATOR from low to high voltage, you can just change the stationaty fields (outer windings) and it will work ok on low amperage output situations. However, to do that in high amp output applications, the heat generated can melt the solder in the armature. "throwing lead". Also in generator operations, the regulator has to control both the field and output sides of the unit so here it is recomended to replace the armature also as the size of the wire in the armature will require a resetting of the voltage regulator to get "proper" operation. More important in changing 12 to 24 than from 6 to 12 because of wire cross section size. In Alternators, most types have the field windings wrapped onto the rotor itself and revolves with the metal poles. However in some, the windings are stationary and the metal poles revolve between the windings and the stator. Does the same thing, but saves turning the copper wire (hp) and preventing dreakdown in the insulation. Here there are no brushes as the excitation is fed direct onto the wire ends. Now there are some constant output alts made with permanent magnents revolving around a fixed stator and uses no regulator. Mostly low amperage units on boats, motorcycles, lawn mowers ect. There are some two phase units being produced in this area also. Some are regulated and some not. As I told Henry, changing from 12 to 24 by changing the field windings is ok as on 24vts less amperage is needed to run most anything on a coach. The total output will, in most cases, be a little less on top end, where the most heat is generated, but in his situation he probably will never get up to that output anyway. I run my total electric Eagle on 24vts by choice and use a 100 amp Motorola alt. Been working for 5 1/2 yrs now. By the way, the automotive industry is changing to dual voltage, starting this year, to 12/42 vts with the intention of being completly 42vts in short order. We will see electric brakes, steering, water pumps. ect. I have already seen prototype cars with this and no camshaft- electric solenoids, computer controlled, running the valves. No starter, as it fuels and fires the cyls electrically. The times, they are changing !!! Hope some of this rambling answered some of what you asked. | ||
| Gene R (12.13.175.111)
Rating: N/A |
Ace,Glad you didn't hug me!!!! The wife is a lot better now, thanks. Our snow is gone as it never lasts over two or three days here. Don't rebuild that unit. The 105 Leece-Neville in its original form was a super good unit. However, some unknown company bought Motorala, Leece-Neville, Prestolite, and the remains of Auto-Lite. One by one they have gone down the tube. They are still producing the "Load-Handler" one wire unit, under the Leece-Neville name and is a good unit. I have a 24vt unit on my coach now. Works fine. As for the 105 unit you asked about, the replacement parts are being made in India and some other countries. The quality stinks!!!! We will try not to repair these units any more as we will see them come back again because of the replacement parts. We replace the unit with a new Delco 21SI series now. They have a year warranty, one wire hookup,(built in regulator) and give little problems. You can get them at most alt shops. They cost me about 90.00 new, less pulley, so don't pay too much. The L/N puley will fit the Delco. Hope this helps, Gene R. | ||
| Richard Bowyer (Drivingmisslazy) (65.207.109.124)
Rating: N/A |
Gene, thanks very much for the detailed reply. I really hate to get just a yes or no answer to a question. Since Henry will be doubling the voltage, then he should limit the current to one half to keep the same overall power rating of the alternator the same, correct? BTY, this only needs a yes or no. LOL Richard | ||
| Gene R (12.13.175.93)
Rating: N/A |
Richard, yes and no. How's that??? Actually you are right about keeping the output to half the 12vt rating after changing the field winding to 24 vts., but if the cooling capacity of that 50Dn has not been altered, the unit can stand more than half the rated output. In most cases like what Henry is doing, he would probably need less than half the output anyway, so there is no problem. Heat is the main factor here. Most automotive (bus) alternators have only about a 70% duty cycle anyway because of the heat factor. If you have a 100 amp alt and you make it put out 100amps constantly, it will die from that heat in short order. However, as I said above, this is controled by the ability to remove the heat from the unit. The oil cooled units on some coaches is the best thing that ever happned to high output units. Sorry this is not just a yes or no answer, but thought some others reading this would like to know why!!!!! Gene R. |
