Onan DYC Series Operator's Manual And Parts Catalog page 20

B A T T E R Y BEGIN. SPEC. G)
Starting the unit req uires 24-volt battery current. Use
t w o l 2 - v o l t (see SPECIFICATIONS) batteries for a
normal installation. Connect the batteries in series
(negative post of first battery to positive post of
second) as in Figure 13. Necessary battery cablesare
on unit. Service the batteries as necessary. Infrequent
unit use (as in emergency standby service) may allow
the batteries to self-discharge to the point where they
cannot start the unit. If installing an automatic
transfer switch that has no built-in charge circuit,
connect a separate trickle charger. Onan automatic
transfer switches include such a battery charging
circuit.
75 kW and 90 kW models prior to S^ec G use 12 volt battery
current. Use t w o 6 volt, 135 A m p Hour batteries connected In series
for these older models.
W A R N I N G
Do not smoke while servicing batteries. Lead
acid batteries give off explosive gases while
being charged.
S T A R T I N G M O T O R
S O L E N O I D
B A T T E R V P O S I T I V E
C O N N E C T I O N
C O N N E C T N E G A T I V E C A B L E T O
C O N V E N I E N T B O L T O N E N G I N E
TME C O N N E C T I O N M U S T B E C L E A N
A N D P A I N T F R E E
B 3 4 8
2 - 1 2 V O L T . 2 2 5 A M P / M R
B A T T E R I E S
FIGURE 13A. BATTERY CONNECTION
2 12-VOLT 225 AMP/HR
BATTERIES
If unit is installed with a tranafer switch, a battery installation as
shown In Figure 13A. must be used. The batteries are mounted
outside the skid.
CIRCUIT
BREAKER
TWO, 12 VOLT, 74 AMP
HOUR BATTERIES
FIGURE 13. BATTERY CONNECTION
BATTERY, HOT LOCATION
Batteries will self discharge very quickly when in-
stalled where the ambient temperature is consistently
above 90° F (32.2° C) such as in a boiler room. Tb
lengthen battery life, dilute the electrolyte from its
normal 1.275 specific gravity reading at full charge to
a 1.225 reading. The cranking power is reduced
slightly when the electrolyte is so diluted, but if the
temperature is above 90° F (32.2° C), this should not
be noticed. The lengthened battery life will be worth
the effort.
1. Fully charge the battery.
2. With the battery still on charge, draw off the
electrolyte above the plates in each cell. DO NOT
ATTEMPT TO POUR OFF; use an hydrometer or
filler bulb and dispose of it in asafe manner. Avoid
skin or clothing contact with the electrolyte.
3. Refill each cell with distilled water, to normal
level.
4. Continue charging for 1 hour at a 4 to 6 hour
rate.
5. Test each cell, If the specific gravity is still above
1.255, repeat steps 2, 3, iand 4 until the reading is
reduced to 1.225. Usually, repeating steps twice is
sufficient.
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