Haulotte Group 3522A, Руководство по техническому обслуживанию оператора

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HAULOTTE GROUP 9 AXLE AND RELATED COMPONENTS
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MAINTENANCE (CONTINUED)
TABLE 9-5. TIRE WEAR DIAGNOSTIC CHART
HOW TO MEASURE VOLTAGE
System voltage is measured at the magnets by connecting the voltmeter to the two magnet lead
wires at any brake. This may be accomplished by using a pin probe inserted through the insulation of
wires. The engine of the towing vehicle should be running when checking the voltage so that a low
battery will not affect the readings.
Voltage in the system should begin at 0 volts and, as the
controller bar is slowly actuated, should gradually increase to
about 12 volts. If the controller does not produce this voltage
control, consult your controller manual.
The threshold voltage of a controller is the voltage applied to
the brakes when the controller first turns on. Lower threshold
voltage will provide for smoother braking. If the threshold
voltage is too high, the brakes may feel grabby and harsh.
HOW TO MEASURE AMPERAGE
System amperage is the current flowing in the system when all the magnets are energized. The
amperage will vary in proportion to the voltage. The engine of the tow vehicle should be running with
the trailer connected when checking the trailer braking system.
One place to measure system amperage is at the BLUE wire of the controller, which is the output to
the brakes. The BLUE wire must be disconnected and the ammeter put in series into the line.
System amperage draw should be as noted in the following table. Make sure your ammeter has
sufficient capacity and note polarity to prevent damaging your ammeter.