I have the $700 50 amp Plane Power alternator in my 'coupe. I replaced the Ford/Cessna 150 style alternator and voltage regulator that was on the airplane when I bought it after I started having problems. The entire draw on the system is about 15 amps and I have a GPS, Electric ADI, Electric T&B, Grimes beacon, dual landing lights, Electric oil gauges, and lots of cockpit lighting. The main advantage to that over the Ford alternator is lighter weight. I can't imagine that you would need anything more that 35 amps for an Ercoupe, though.
--- In ercoupe-tech@yahoogroups.com, "dtaylor9319" <dtaylor9...@...> wrote: > > > > In my copy of Coupe Capers, I have seen for sale a kit to convert my existing > Delco Generator to a new fancy alternator. Cost is around $700. If I find > that my Delco 35 amp generator needs replacement, would there be any real > benefit, or problems with converting to an alternator. Up til now, everything > has been working fine, no radio problems or circuit breakers popping out, > lights working, no smoke in the cockpit. I would really rather stay with the > old generator if there will be little or no good to come of switching to an > alternator. Is the 35 amps the generator enough? I would think the alternator > would produce 50 amps at least, but do I really need that much. > > --- In ercoupe-tech@yahoogroups.com, Iflysmodel@ wrote: > > > > Hey DTaylor: I am no expert, but here are some of the things to check/try: > > It is very easy to test the generator on the plane. The test is > > definitive. > > > > Disconnect the ground from the battery. Remove all the wires from the > > generator. Connect a volt meter between the armature of the generator and > > the generator case (ground). Connect a jumper wire from the field terminal > > to the generator case. Start the engine. Voltage should track RPM's and > > reach 13-14 volts by the time you get to about 1500 RPM (probably sooner). > > If this test fails connect the volt meter from the field terminal to ground > > and repeat. If you get a volt or two, the generator is bad. If you get > > nothing flash the field then repeat the first test. > > > > Troubleshooting Alternator and Generator Issues: > > > > > > DC Charging systems can be identified as "A" or "B" circuit. It is > > necessary for the technician to determine > > which system he has in order to properly troubleshoot. The "A" system > > controls the output by regulating the > > field circuit to ground. The "B" circuit controls the output by > > regulating > > the battery to field. > > > > All Delco Remy Generator charging systems are "A" circuit, therefore their > > regulator controlled how much > > ground was placed on the generator field circuit. This was originally > > accomplished by a vibrating point system > > in the voltage regulator. The more the points were vibrating toward the > > closed position the more the output. > > The further apart the points were during the vibrating function, the less > > the output. > > > > The solid state generator controls work by controlling the generator field > > to ground through a system of > > electronic components rather than the vibrating points. The theory > > remains > > the same, the more ground on > > the generator field, the more output and vice versa. > > > > Most general aviation alternators are "B" circuit. In order for them to > > output current from the alternator, > > battery must be applied to the field. The more battery to field, the > > higher > > the output. The regulator is then > > assigned the task of controlling the amount of battery to field. There > > are > > some general aviation charging > > systems that are of the "A" circuit type. These are normally found in > > Prestolite alternator systems with two > > field terminals on the alternator. If neither of the fields is grounded > > to > > the frame of the alternator, then > > the system is "A" circuit. This simply means that the voltage regulator > > is > > controlling the alternator field > > to ground to control output. > > > > The reason it is important for the technician to determine whether the > > system is of the "A" or "B" style is so > > that they can proceed to diagnose the system. A common method of > > diagnosing > > charging system problems begins > > with the full field test. This test is used as a method of determining > > whether the generator or alternator is > > functioning. Since the regulator controls how much battery or ground is > > being applied to the generator or > > alternator, the full field test requires bypassing the regulator and > > jumping full ground or battery to the > > field circuit. This causes the generator or alternator to charge at full > > output when rotated at cruise RPM. > > > > If you are testing a Delco Remy Generator system, remove both the armature > > and field wires from the generator. > > To prevent damage, cover the wire ends with tape. Next, jump the field > > post > > on the generator to a good airframe > > ground. Connect a DC voltmeter to the generator armature terminal. > > Connect > > the plus side to the post and the negative > > side of the meter to ground. With the field grounded the generator, if > > good, will generate a voltage on the armature > > terminal. The voltmeter should follow the throttle. The more engine > > speed > > the more output. Using a digital meter in > > this application is sometimes not effective. An analog (needle movement) > > meter is much more reliable. > > > > Should you have a Generator that is not Delco, it could possibly be of > > the > > "B" circuit, Field to Battery, type > > application. If so, follow the instructions in the previous paragraph, > > except connect the jumper from the Armature to > > the Field post. Then connect the meter from the armature post to ground > > and measure the output voltage. Normally, > > the generators manufactured by Bendix, General Electric and Leece Neville, > > > > adopted the "B" circuit method. > > > > When testing general aviation alternators, the brands encountered will be > > Ford, usually found on Cessna and Chrysler > > on most older Pipers. You might also run across Delco Alternators on > > various models of Piper and Beech aircraft. > > Motorola units, in the form of STC approvals by Alcor or InterAv, must > > also > > be taken into consideration. All of these > > unit are "B" circuit requiring a jumper from the Battery post to the > > field > > post in order to "full field". This means > > you must remove the field wire, tape the terminal for protection, and > > connect a jumper from the large output terminal > > over to the field post. Connect your DC voltmeter from the output > > terminal > > to ground and the voltage should then follow > > the RPM if the alternator is good. > > > > In the instances where you have a Prestolite charging system, you must > > first determine whether the system is "A" or > > "B" circuit. If the alternator has only one field post it is "B" circuit > > and requires jumping battery to field. If > > the unit has two field post, normally f1 and f2, disconnect both field > > wires and protect. Now connect one jumper from > > the Battery output post to one field post and a second jumper from the > > remaining field post to ground. This will full > > field the dual field models. The voltmeter is connected from the Output > > post to ground as in the previous example. > > > > If the generator or alternator passes the full field test the next most > > likely culprit is the voltage regulator. A > > fairly reliable quick test is to connect your voltmeter to the wire > > delivering battery to the regulator from the bus. > > This should read battery voltage, either 12 or 24 volts depending on the > > system. If you are getting good input voltage > > to the regulator, connect your voltmeter to the field circuit exiting the > > regulator. You should read some amount of > > voltage. If the reading is zero the voltage regulator is probably > > defective. > > > > Before replacing the regulator it is always a good idea to measure the > > resistance of the field circuit. This can be > > done at the regulator field wire or on the field post of the generator or > > alternator. The normal reading from the > > field post on 12 volt systems is 4 to 6 ohms. On 24 volt systems this > > doubles to 8 to 12 ohms. This can vary slightly > > and still be considered normal. > > > > > > > > In a message dated 7/12/2010 4:32:22 P.M. Eastern Daylight Time, > > dtaylor9319@ writes: > > > > > > > > > > Went to fly Saturday morning and found a sharp discharge on the Amp Meter > > when electronic circuits were turned on. Ran up to 2100RPM with nothing on > > but the radio and got no positive indication. Where do you start to sort > > out > > what the source of the problem is. Cigarette lighter plug in voltmeter > > shows 11.2 volts. 1966 Alon Aircoupe with a C90 16F. Has generator not > > alternator system. > > >
