PREVOST LE MIRAGE XLII BUS SHELLS, Руководство по обслуживанию

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Section 06: ELECTRICAL
PA1564
17
FIGURE 15: LOAD TEST
06064
2. Apply a 290 amperes load to the battery for
15 seconds.
3. With an ammeter reading specified load,
read voltage. The voltage should be at least
9.6 volts. Disconnect the load. If the
voltmeter indicates 9.6 volts or more, the
battery is good. If the voltmeter reading is
less than 9.6 volts, replace the battery. This
voltage is to be used for battery ambient
temperatures of 70ºF (21ºC) and above. For
temperatures below 70ºF (21ºC), refer to the
following
"Voltage and Temperature Chart" .
Voltage and Temperature Chart
Ambient Temperature Minimum Voltage
70ºF (21ºC) and above 9.6
60ºF (16ºC) 9.5
50ºF (10ºC) 9.4
40ºF (4ºC) 9.3
30ºF (-1ºC) 9.1
20ºF (-7ºC) 8.9
10ºF (-12ºC) 8.7
0ºF (-18ºC) 8.5
NOTE
The accuracy of this test procedure is
dependent upon close adherence to the
proper load, time and temperature
specifications.
3.5.4 Testing Battery Cables
Check all cable ring terminals and connections to
determine if they are in good condition.
Excessive resistance, generally caused by poor
connections, produces an abnormal voltage drop
which may lower voltage at the starter to such a
low value that normal operation of the starter will
not be obtained. An abnormal voltage drop can
be detected with a low-reading voltmeter as
follows:
DANGER
To prevent the engine from starting, the DDEC
engine circuits, which are protected by
breakers (CB-1 & CB-2) located in the circuit
breaker panel, must be deenergized during
these tests; afterward toggle yellow lever
upwards to reset the circuit breakers.
1. Check voltage drop between grounded
(negative) battery terminal and vehicle frame
by placing one prod of the voltmeter on the
battery terminal and the other on a good
ground (unpainted surface) on the vehicle.
With the starter cranking the engine at a
temperature of 70ºF (21ºC), voltage reading
should be less than 0.3 volt. If the voltage
reading exceeds 0.3 volt, there is excessive
resistance in this circuit.
2. Check voltage drop between the positive
battery terminal and the starter positive
terminal stud while the motor is operated. If
the reading is more than 2.5 volts, there is
excessive resistance in this circuit.
NOTE
If it is necessary to extend the voltmeter lead
for this test, use a #16 (AWG) or larger wire.
3. Check voltage drop between the starter
housing and a good ground on the vehicle.
The reading should be less than 0.2 volt.
DANGER
Any procedure other than the following could
cause personal injury or damages to the
charging system resulting from battery
explosion or electrical burns.
Wear adequate eye protection when working
on or near the batteries. Ensure that metal
tools or jumper cables do not contact the
positive battery terminal (or a metal surface in
contact with it) as a short circuit will result. Do
not attempt to jump start a vehicle suspected
of having a frozen battery because the battery
may rupture or explode. Both the booster and
discharged batteries must be treated carefully
when using jumper cables. Follow exactly the
procedure outlined later in this section, being
careful not to cause sparks.