We have assembled a list of frequently asked questions about alternators and supporting tech. Whether it’s about part numbers or settings, you’ll find the most popular questions and answers below. If you don’t see your question, please contact our product support department.

Generators installed on the older, small Continental engines could have one of two different size armature shafts. The smaller and by far the most common shaft is .5” diameter. However, some shafts installed may be larger .64” diameter. You will not know this until the generator is removed for inspection.

If the replaced generator had the larger shaft (.064”), the ER14-50 installation will require the use of the G-Pack. If the replaced generator had the smaller shaft (.50) the ER14-50 installation may use the existing gear assembly.  The ER14-GR can be used in place of the G-Pack if a new alternator to engine gear is needed at the same time.

E-Series engines (E-165, E-185, E-225) use a unique gear and CANNOT use the gear included in the ER14-50 assembly. However, the G-Pack can be used to size the shaft properly if required. But, the ER14-GR gear assembly CANNOT be used to replace a missing/damaged gear as it is NOT compatible with the E-Series engine drive gear.

The C28-150 and the C28-150FR are the same in fit, form and function. The FR (factory rebuilt) designation was required BY a manufacturing process when the product line was originally purchased. That process is no longer required so the FR designation was dropped.

The ALE-1013AS brush is perfectly square and is used with the ALU or ALE-3045BS brush holder. The ALE-2013AS brush is slightly rectangular and is used with the ALU or ALE 2045BS brush holder. The brushes are not interchangeable.

The R1224 and the R1224B voltage regulators are the same electrically. The only difference is the size of the base.

There are no manuals approved on the ASG/991 series alternators as there are no repairs or field overhauls approved. These alternators are considered “on-condition” until they are no longer serviceable.

The Plane Power warning light is a 100 milliamp bulb. If an incorrect bulb is used, the light may not come on or it may “glow in the dark”.

The front seal used on most of the gear drive, Permold style alternators is part number XA-1026.

The brush block assembly used in the Plane Power AL12 and AL24 series alternators is part number 10-1020.

The brush block/regulator assembly used in the Plane Power C14-50, EX14-50 and AL12-EI60 alternator is part number 11-1043.

The brush block assembly used in the Plane Power ER14-50 alternator is part number 11-1013.

The brush block/regulator assembly used in the AL12-RI70 Plane Power alternator is part number 99-1042.

The brush block assembly used in the Plane Power ALT-FLX, C14-100 or C28-150 alternators is part number 15-5005.

The enable harness for the AL12-EI60 and ER14-50 Plane Power alternators is part number 11-1010.

The enable harness assembly for the Plane Power AL12-EI70/B alternator is part number 99-5097.

The Plane Power AL12-EI60 series alternator regulator is factory set to 14.2+/- .3 volts.

Wide deck engines will always have letter at the end of the serial number. Narrow deck engines will not.

The 14-1010 14 volt Plane Power lamp has yellow leads. The Plane Power 14-1011 24 volt lamp has purple leads.

R1224 voltage regulator wiring diagrams can be found in the Installation Manuals under the Support drop down on the planepower.aero website.

The RH24-70 alternator is a proprietary unit manufactured exclusively for Robinson Helicopters. As such, you will need to contact them regarding recommended service (ICA) and TBO.

Please see the product line home page, select “Support” and then “Warranty”.

Please see the product line home page, select “Support” and then “Warranty”.

If parts and/or labor are approved under the commercial portion of the ASB or SB, complete the claim form at the end of the bulletin and return to the physical or email address provided in the ASB or SB.

Within 12 months from date of invoice, any unit returned for core shall be as removed from the aircraft, be complete and not disassembled. The core must be identified with an original data tag. Missing data tags or original ink-stamped identification will not be accepted. A percentage of the core value will be charged for all missing or damaged parts.

Any product returned for warranty consideration shall be as removed from the aircraft, be complete and not disassembled. All external parts including, but not limited to, brackets, fittings, bafflings, etc. shall be removed prior to shipment as they will not be returned.

Go to the hartzell.aero website and select Videos under the Resources heading.

You need to follow the aircraft manufacturer’s recommendations for start-up/shut-down procedures if published. However, if not published, the field switch should always be off when the engine is started. There is no reason to subject the electrical system, alternator, and regulator to the power fluctuations during the starting/shut-down process. Once the engine is started, and has stabilized, turn on the field switch and add bus load.

The “S” designation indicates a “slim” version of the alternator which basically means there is no factory installed debris shield or cooling tube.

The FS1-14 internal, non-adjustable regulator is set at 13.6+/- .2 volts. This alternator would be used as a back-up to an AL12-EI60 main alternator kit and would come online automatically if system voltage drops below 13.6 volts as in a failure of the main alternator.

The FS1-14B internal, non-adjustable regulator is set at 14.2+/- .2 volts and can be used as a stand-alone alternator system for aircraft wanting the lightest weight and using minimum equipment.

Because both alternators are driven from a slower accessory pad drive, these alternators will not produce output to support load until they reach approximately 2000 engine rpm. Perfect for a back-up system should the main alternator be lost in flight but limited as a stand-alone system as any installed equipment would be running off the battery during taxi and landing configurations.