Yamaha UMAX, Руководство по обслуживанию

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ELECTRICAL COMPONENTS (YUM2E)
8-73
7. Compare the readings.
8. Check the state of charge using the table 2.
Table 2
9. If any specific gravity reading still registers
lower than the factory specification of 1.277 ±
0.007, then one or more of the following con-
ditions may exist:
a. The battery is old and approaching the
end of its life.
b. The battery was left in a state of discharge
too long.
c. Electrolyte was lost due to spillage or
overflow.
d. A weak or bad cell is developing.
e. Battery was watered excessively before
testing.
Batteries identified with any one of the condi-
tions listed in items 9a through 9e should be tak-
en to a specialist for further evaluation or retired
from service.
Open-Circuit Voltage Test
For accurate voltage readings, batteries must
remain idle (no charging, no discharging) for at
least six hours, preferably 24 hours.
1. Disconnect all loads from the batteries.
2. Measure the voltage using a DC voltmeter.
3. Check the state of charge with the table in
“Specific Gravity Test”.
4. Charge the battery if it registers 0% to 70%
charged.
5. After charging, if battery registers below the
table in “Specific Gravity Test” values, the
following conditions may exist:
a. The battery was left in a state of discharge
too long.
b. The battery has a bad cell.
Batteries in these conditions should be taken to
a specialist for further evaluation or retired from
service.
Discharge Load Test
WARNING
Batteries generate explosive hydrogen gas.
Always follow these precautionary mea-
sures:
• Charge batteries in a well-ventilated area.
• Keep batteries away from sparks or open
flames (e.g., welding equipment, lit ciga-
rettes, etc.).
• Do not smoke when charging or handling
batteries.
The purpose of the discharge load test is to de-
termine how many minutes it will take to bring
the total voltage of a fully charged 48 V battery
pack to 42 V. This test represents the maximum
work or runtime capability of a 48 V battery pack
at 26.7 °C (80 °F) to fall to 42 V.
Sixty minutes should deliver 36 holes of golf for
most courses. A shorter time period will indicate
that one or more of the batteries needs service
or replacement.
When you are load testing, you will need a load
tester and a high-quality digital voltmeter capa-
ble of reading at least 55 V DC. Yamaha recom-
mends using the Lester 17770 Battery
Discharge Unit.
State of Charge as related to specific gravity
and operating circuit voltage
Percentage of
Charge
Specific Gravity
Corrected to
26.7 °C (80 °F)
Open-Circuit
Voltage 48 V
100 1.277 50.93
90 1.258 50.47
80 1.238 49.99
70 1.217 49.49
60 1.195 48.96
50 1.172 48.41
40 1.148 47.83
30 1.124 47.26
20 1.098 46.63
10 1.073 46.03
DISCHARGE TESTER 36/48V
LES-DISCH-AR-GE