By John Smith
Times have changed since Bob Jeffries secured one of his first jobs in the trucking industry. In 1978, when he worked starting trucks as part of his duties on a fuel island, he could be confident that the engines would remain running until the end of the day.
“Now we see applications where the starts can be as high as 80 to 120 per day,” observes the industry veteran, now the manager of fleet operations and service for Remy Inc., the maker of Delco Remy alternators.
Trucks that operate in urban environments face the demands of stop-and-go traffic as well as the anti-idling legislation that limits the opportunity to recharge batteries. These are only a few examples of the challenges that have emerged for electrical systems.
A modern refuse vehicle, for example, can draw between 240 and 280 amps when all four stages of the electronic brake retarder are engaged. “There is no alternator in the world that will handle that at full idle,” Jeffries notes.
To compound matters, an OEM that chooses the size of an original alternator may be unaware of a vehicle owner’s plans to add a lift gate or a snowplow with a 12-volt DC motor. Some Auxiliary Power Units also will need to have batteries of their own.
“If we consider the sleeper area of the cab, there are unlimited types of additional amperage demands that might be lurking in there – from microwaves, to TVs, to game systems, to climate controls,” adds Fred Padgett, Robert Bosch’s group product manager, starters and alternators.
