Pierce Enforcer, Operator'S Manual

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© 2018 Pierce Manufacturing Inc. All Rights Reserved.
Electrical / 6-19
MAINTENANCE
Inverters are electronic devices used to change Direct Current (DC) to Alternating Current (AC). Some inverters
contain converters that also convert AC to DC for battery charging and/or running 12V equipment.
6-16.5 Before Servicing High Voltage Equipment
• Be aware of ALL high voltage equipment on the vehicle; review the high voltage equipment found on the
electrical diagrams and in the service manual
BEFORE starting any work.
• When working on this equipment, remain alert at all times. Never work on the equipment when you are
physically or mentally fatigued and never work alone near high voltage equipment.
• Always stand on an insulated, dry surface when working on any electrical circuit. Do not handle any kind of
electrical device while standing in water, while barefoot, or while hands or feet are wet.
• Always work in an adequately illuminated area.
• Always use appropriate protective equipment: insulated gloves, rubber gloves, goggles/face shield, safety
shoes, protective clothing, and insulated tools when working on electrical components/circuits of the vehicle.
• Never wear jewelry when working on this equipment. Jewelry can conduct electricity, resulting in electrical shock
or burns, and may get caught in moving components causing injury.
• When working on vehicles that have high voltage devices or equipment, use appropriate alerting techniques in
plain view to warn people that may be in the general area and to prevent inadvertent activation of any disabled
high voltage circuit(s) during service: safety signs, safety symbols, tags, barricades, cones, etc.
• Keep a fire extinguisher close by at all times. Extinguishers rated "ABC" by the National Fire Protection
Association are appropriate for use on the electrical system. Make sure the extinguisher is properly charged and
be familiar with its use.
• Ensure that the high voltage power, high voltage power generating equipment, and high voltage storage devices
are disconnected, locked out, or otherwise disabled BEFORE working on or around the vehicle, its electrical
circuits, or components. Unless disabled, Auxiliary Power Units (APUs) may start at any time without warning;
when this occurs, the circuits associated with the APU become energized with potentially lethal high voltage.
Some components may require a waiting period or special procedures to discharge the voltage completely.
• Use an appropriate electrical tester and procedures to confirm that the power is disconnected BEFORE
performing any work on or near any high voltage components/circuits.
• Exercise caution around output circuits even when the input power is off. Parallel power sources and energy
storage devices can still be dangerous. Be familiar with the high voltage equipment installed on the vehicle.
Some systems contain high voltage condensers that may require time to discharge after power is removed.
• After disconnecting or exposing a high-voltage connector or terminal, insulate it immediately using insulation
tape.
• After completion of any electrical work, BEFORE restoring the power, verify that parts and or tools are removed
from the work area and that the fasteners are firmly tightened to the specified torque and the connectors are
correctly connected.
• Voltage can be fatal at levels greater than 60 volts. High voltage can jump a larger air gap than low voltage. If
contact is made with high voltage it may not be possible to simply "let go".
• If a high voltage fuse or circuit protection device trips, do not re-energize the circuit until it has been determined
that the circuit is safe. See manufacturers troubleshooting procedures before servicing a high voltage system.
• Reference OSHA Regulations as necessary and applicable.