Generac Power Systems 53187 - Manual (Page 112)

SECTION 5.2
ENGINE CRANKING SYSTEM
I
PARTS
ENGINE ELECTRICAL SYSTEM
Type 1 Engine Cranking System (Continued)
THE BATTERY (CONT’D):
2. Hold the current draw for 15 seconds. Then, observe
battery voltage. If the voltage remains at 9.6 volts or
more, the battery Is good. If battery voltage drops below
9.6, go to Step 3.
3. Connect the battery to a charger and set the charger
to Its fast charge rate. DO NOT EXCEED 40 AMPS.
After three (3) minutes, check the voltmeter reading. If
reading is greater than 16.5 volts, replace the battery.
If desired, the battery can be tested using an automo­
tive type battery hydrometer. Check the battery for both
(a) state of charge and (b) condition, as follows:
1. Follow the hydrometer manufacturer’s instructions
carefully. Draw a sample of the battery fluid from each
battery cell, one cell at a time. Read the specific gravity
of the fluid, then return the fluid to the cell from which it
was drawn. As the specific gravity reading of the fiuid
from each ceil is taken, write the reading down.
2. If the hydrometer being used does not have a "Per­
centage of Charge scale, compare the readings with the
following:
SPECIRC GRAVITY PERCENTAGE OF CHARGE
1.260 100%
TS’JS
TT553 55^5
T7T75 25%
3. If necessary, remove the battery and recharge it to a
100% state of charge.
4. If the difference in specific gravity between the
highest and lowest reading cell is 0.050 (50 points) or
more, the battery is nearing the end of its useful life and
should be replaced.
5. If the highest reading obtained is less than 1.200,
recharge the battery then retest specific gravity, if the
difference between the highest and lowest reading is
still more than 0.050 (50 points), replace the battery.
10 AMP CIRCUIT BREAKER (CB3):
General: The 10 amp circuit breaker (CB3) is physi­
cally mounted on the generator control panel. It is
electrically connected in series with the battery power
supply to the engine control circuit board. Should the
circuit breaker trip open due to an overload, or if it is set
to its OFF or OPEN position, engine cranking and
startup cannot occur. In addition, the preheat function
will not be possible when the breaker has opened.
Schematic
_
Pictorial
r
1 1 '■ «TAHTiMa
CB3
)
1 © • (
i 1 •
m
f II Ml
15A l| M *•/»» >o M c •»*»
Figure 2. The 10 Amp Circuit Breaker
14 AMP FUSE:
Should the fuse element melt open due to an over­
load, engine cranking and startup will not be possible.
If the fuse must be replaced, use only an Identical 14
amp replacement fuse.
Schematic Pictorial
15A ■
i
1
' ....... . I»««
© •
•S 14 AH»
• m
Figure 3. The 14 Amp Fuse
CRANK RELAY (CR1):
The crank relay (CR1) is energized by battery voltage
when the starl/stop switch is set to Its "Start" position.
When energized, the relay’s nonmally-open contacts
close to perform the following functions:
DDeliver 12 volts DC to the engine control circuit
board, for board operation while cranking.
□connect Terminal 3 of the engine control circuit
board and Wire 17A to ground. The circuit board
then responds by energizing a starter contactor to
initiate engine cranking.
□Deliver 12 volts DC to the engine preheat circuit.
PAGE 5.2-2