Easy conversion, external voltage regulator to internal
Patrick1244 said:
I have a RV6A with a 0360 A1A.
My current Alternator died and I am replacing it with a new 60amp that has the voltage regulator built in. My old alternator had a voltage regulator mounted on the firewall. Do I just need to disconnect the old voltage regulator? Any info would be appreciated.
The alternator I bought was from Vans, part number 14684N.
If you send me the wire diagram for your OLD alternator, regulator, switch and wire protection (CB / fuses) I can help you.
Here is a little drawing I made (click to enlarge):
Here is one from a generic Toyota:
The internal regulated alternator has ONLY two wires that are mandatory to connect. The third wire, warning light, or "L" is recommended, but may require you to run a new wire and install a lamp in the panel, if you don't have one now. The warning light is not required and is optional. If you don't want to use the warning light or idiot light, than leave it disconnected. The alternator you have is connected has the following:
First wire is the main output of "B-lead" goes to the battery. It is the big threaded stud on the alternator, that's not part of the round connector plug. This should be the same as the old unit. This old B-lead should be the same?? The B-lead usually or typically goes thru a panel mounted circuit breaker or fuse than the main buss or battery. Its a homebuilt so who really knows how it is wired, but you can trace it visually. Some will run the B-lead thru a large fuse and direct to the battery? Write me and let me know. ITS A GOOD IDEA TO LABLE ALL THE WIRES AND DRAW OUT A SCHEMATICS.
Now for the other one or two wires. The connector plug has three positions, one is a dummy, one is the IGN and the one is "L" or lamp.
Second wire (required) is the IGN or ignition wire is connected to the alternator thru a switched positive 12 volt off the main buss. This tells the alternator to be ready to work or go to sleep before engine start or after shut down. This is usually turned on with a split type Cessna MASTER BAT/ALT switch or separate switch typically labeled as the ALT. Another way is a single toggle which as DOUBLE POLE single throw. This wire should also be protected with a CB or fuse connected to the main buss.
With your current external regulator there may be an equivalent "IGN" wire you can just extend from where the old regulator was to the alternators IGN lead at the plug. Unlike your old alternator, the drain or current on this wire for an internally regulated alterantor is very small, less than a 1/2 amp. Where the external regulator took as much as 4-5 amps. So the wire gage should be good and the fuse or CB more than large enough, but could be sized smaller, say 1 amp, at your option.
Third wire and last one, is optional. It's an idiot light or a no-charge lamp labeled "L". You can choose to not use it, but I think its worth hooking up. Just follow the directions. It requires wire, *lamp/lamp holder and wire protection, CB or fuse (even in-line fuse) and 12v buss power. No switch is needed. Your existing external voltage regulator may have had a no charge light feature or may not or may not have been installed?
If you don't have an existing NO CHARGE light you should add it. This would be a good cheap way to add a no-charge / low volt idiot light if you did not have one before. You can use a lamp up to 1 amp or a little LED lamp, but the LED may require a in-line and/or parallel resistor to make it work correctly. LED's run off of very low voltage and current, so an in-line resistor is may be needed to drop the voltage down. Also a "drain" resistor may be needed because LED's use so little current, a little leakage from the alternators lamp driver transistor may make the LED glow, all the time. We can work that out later.
Your old regulator may have any of these terminals like, I, FLD, A or BAT, S, N, G.
I=light/ignition, FLD=field, A=(+) battery power; BAT=(+) Battery, S=Stator, N-neutral, G=ground. Here are the wires you may be able to use again?
The old "A" wire could be used for the new alternators IGN wire?
The old "I" wire could be used for the new alt's charge lamp or "L" wire?
The old BAT could be like "A" above?
The FLD is not used in the new installation.
S and N stator/neutral wires are not used in the new installation.
You have to trace the wires and know where they where connected to make sure. I can't guess at what you have.
After you figure out what you have, write me off list with the OLD type of alternator, regulator model and description of connections and labels, if you like. I can help you. Make sure you label wires, take notes and make a diagram of your charge system, for your own reference. I don't know your background and how much you understand about alternators. This could all be old hat? Sorry if it is. It ain't hard but you do have to wire it correctly for maximum reliability and service. Failure to do it properly could burn out your alternator or cause it to operate erratically, causing other problems. Wired properly it will be dead nuts reliable and be trouble free.
Good Luck (
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