The Harmony 25 is equipped with six 12 volt, 100
amp hour Concorde Lifeline deep cycle marine batteries. These are Absorbed
Glass Mat (AGM) lead acid construction. AGM batteries have several advantages
over standard wet lead acid batteries:
1) They are sealed so do not need
water added periodically. This means no maintenance plus the batteries do not need to be readily
accessible thus permitting a more flexible interior design.
2) They have
less internal resistance so are more tolerant of rapid charge and discharge.
This makes more of the battery's total energy available at typical cruising
3) They have a much slower self-discharge rate so can be left
untended for months without going dead.
4) Even without maintenance they
last longer than conventional batteries. Concorde rates them for 500 cycles
at 80% depth of discharge and 1000 cycles at 50% depth of discharge. They
could easily last eight to ten years or more in normal service.
There are three batteries under the cockpit table, one
under the fore deck and one under each of the side seats.
|| EPIC Whisper speed control box. The throttle joystick creates an
input signal for speed and direction. This device creates the three
phase alternating current waveform to drive the motor in the intended
speed and direction. It also has several safety features such as the
motor won't start if the key is turned on when the joystick is not
in the neutral position and the power will automatically cut back
if the unit overheats.
|| Main circuit breaker/switch to isolate battery voltage from all
|| Sevcon 12/72 converter. This steps down the 72 volt battery output
to 12 volts for the lights and stereo.
|| Fuse panel for 12v circuits.
||Delta-Q Battery charger. Regular household 120v A/C input, 1000
watt output to charge 72 volt battery bank. The charger is programmed
by Delta-Q specifically for the 12v AGM batteries. It can be left
plugged in indefinitely and can recharge the batteries in about 8
|| Motor well.
||Power tilt actuator. A switch on the dashboard raises and lowers
the motor. A safety release will allow the motor to kick up if it
strikes an underwater object.