PREVOST X3-45 Multiplex, Руководство по обслуживанию

Страница: 247 / 1422

67889: 67889:
Incorporated
Testing and Trouble Shooting
BATTERY EQUALIZER OWNER’S MANUAL 11
A) No, the Battery Equalizer electronically limits the output current to a value less than the amount
required to trip the circuit breaker. (Extreme conditions, such as 28 VDC input with 8 VDC output
at very high ambient temperatures, may cause the circuit breaker to trip.)
Q) Why is the Battery Equalizer' s circuit breaker value lower than its output current rating (35 amp
circuit breaker in model 60-50A)?
A) The circuit breaker is in the ground circuit. Due to the equalizer’s two to one (24/12 VDC) voltage
conversion, the model 60-50A requires 25 amps at 24VDC input to produce about 50 amps
output at 12 VDC. Therefore, a 35 amp circuit breaker in the GND circuit will properly protect for
the maximum 25 amp rating.
Q) What causes the circuit breaker to trip on a Battery Equalizer?
A1) The Battery Equalizer' s circuit breaker is designed to trip when the +12 volt to GND terminals are
exposed to reverse polarity.
A2) With the Battery Equalizer' s GND terminal connected to chassis and the battery negative terminal
disconnected, a short between a +24 volt circuit and chassis will pull the chassis up to +24 volts,
causing a reverse polarity on the +12 volt to GND circuits. The circuit breaker trips to protect the
Battery Equalizer.
A3) With the Battery Equalizer' s GND terminal connected to chassis and the battery negative cable
disconnected, 24 volt loads (e.g., starter motor) will pull the chassis up to +24 volt causing a
reverse polarity on the Battery Equalizer' s +12 Volt to GND circuits. The circuit breaker will trip to
protect the Battery Equalizer.
A4) Since the above reverse polarity conditions may occur during bus maintenance it is
recommended that the service personnel verify the circuit breaker is IN before releasing the bus
for service and the tour bus operator do the same in his “walk around”.
Q) What are some known conditions that could cause Battery Equalizer problems?
A1) Corrosive liquids or water forced into the Battery Equalizer' s case from high pressure spray
cleaning could shorten the normal life expectancy.
A2) Drilling into the case (except for the mounting flanges) can shorten the life or prevent the unit
from operating. The installer may not realize the Battery Equalizer is not operating correctly
unless a 12 volt load is applied to the system and the Battery Equalizer 12 volt current is
measured.
A3) Too small of wire or bad connections will allow the Battery balance to be less than optimum.
Voltage loss in wire from the battery' s +24 volt terminal to the Battery Equalizer' s +24 volt
terminal should be 0.05 VDC maximum; from the battery' s +12 volt terminal to the Battery
Equalizer' s +12 volt terminal should be 0.10 VDC maximum, and from the battery ground terminal
to the Battery Equalizer' s GND terminal should be 0.05 VDC maximum, when the +12 volt load is
causing the Battery Equalizer to operate at 100% capacity.
A4) Installing the Battery Equalizer in a location where it will be exposed to battery fumes will shorten
its normal life. Acid fumes are heavier than air. Installation of Battery Equalizers on the battery
mounting surface near the bottom of the batteries have caused severe corrosion to the Battery
Equalizers. However, installation of Battery Equalizers 3 or more inches above the top of the
batteries have not caused problems.
Q) Can different models of equalizers be paralleled?
A) Yes, any combination of models from Family 1, Family 3 and Family 4 may be paralleled. Family
2 models may only be paralleled with other Family 2 models.