Electrical Systen1 - Piper CHEROKEE CRUISER PA-28-140 Information Manual

CHEROKEE CRUISER
ELECTRICAL SYSTEM
The electrical system includes a 14-volt 60 ampere alternator, battery, voltage regulator,
overvoltage relay, and master switch relay. The 12-volt battery and master switch relay are
located beneath the baggage compartment floor. Access for service or inspection is obtained by
raising the hinged floor panel. The regulator and overvoltage relay are located on the fuselage
behind the instrument panel.
Electrical switches are located on the right center instrument panel, and the circuit
breakers are located on the lower right instrument panel. A rheostat switch on the right side of
the switch panel controls the navigation lights and the intensity of the instrument panel light.
Standard electrical accessories include starter, electric fuel pump, stall warning indicator,
cigar lighter, ammeter, and annunciator panel *.
Optional electrical accessories include navigation lights, anti-collision light, landing light,
and instrument panel lighting.
The Flite Liner includes as standard electrical accessories: starter, electric fuel pump, stall
warning indicator, ammeter, navigation lights, anti-collision light, landing light, instrument panel
lights, and annunciator panel*.
WARNING
Anti-collision lights should not be operating when flying through
cloud, fog or haze, since the reflected light can produce spatial
disorientation. Strobe lights should not be used in close proximity to
the ground such as during taxiing, takeoff or landing.
The annunciator panel * includes alternator and low oil pressure indicator lights. When the
optional gyro system is installed, the annunciator panel also includes a low vacuum indicator
light. The annunciator panel lights are provided only as a warning to the pilot that a system may
not be operating properly, and that he should check and monitor the applicable system gauge to
determine when or if any necessary action is required.
Circuit provisions are made to handle a full complement of communications and
navigational equipment.
The alternator system offers many advantages over the generator system. The main
advantage is full electrical power output at much lower engine RPM which results in improved
radio and electrical equipment operation. Since the alternator output is available all the time,
the battery will be charging almost continuously. This will make cold weather starting easier.
In generator systems, the ammeter indicates battery discharge. In the Cherokee electrical
system the ammeter displays in amperes the load placed on the alternator. With all electrical
equipment except the master switch in the OFF position, the ammeter will indicate the amount
of charging current demanded by the battery. As each item of electrical equipment is turned on,
the current will increase to a total appearing on the ammeter. This total includes the battery.
The maximum continuous load for night flight with radios on is about 30 amperes. This 30
ampere value plus approximately 2 amperes for a fully charged battery will appear continuously
under these conditions. Do not take off with a fully discharged battery as 3 volts are needed to
excite the alternator.
* Serial nos. 7525001 and up
2-8
AIRPLANE AND SYSTEMS
REVISED: MAY 22, 1980