Alternators and batteries have become more powerful to handle these larger loads, but many technicians are getting caught up trying to analyze complicated systems and making unnecessary repairs when many problems can be solved by remembering a few basic steps.
The role of the technician is evolving to include more electronics knowledge, and while there are new gadgets to help them do a better job, keeping your techs focused on the fundamentals of electrical systems is your best bet for running a productive and profitable shop.
Power-packed alternators are as popular as ever these days, and Pete Sremac, commercial market manager for the Evanston, IL-based alternator manufacturer C. E. Niehoff & Co., says their brushless design helps maintain an efficient electrical system for big rigs that need plenty of juice for long hours of idling.
"When you've got a 10-kilowatt or a big alternator like that, the difference in efficiency can equate to several horsepower because it takes about 25 horsepower to drive an 18-kilowatt alternator," he says. "Now you're getting into something that's more significant that begins to be noticeable in fuel consumption. It adds up over time and we've done some calculations in fuel savings over time based on full output from these large alternators (heavy-duty transit bus), and you can save about 1,000 gallons a year, depending on the duty cycle."
It's all part of the drive to satisfy the growing demands of the industry, says Sremac.
"Years ago, 200 amps on a bus was OK, but now it's 300 or 400 or more," he says. "It's the same with emergency vehicles—they are looking 400-500 amps as a normal electrical output. Radios and computers don't take a whole lot of power, but they've got a whole lot of them. It all adds up."
C. E. Niehoff engineer James Becker says the result can damage even powerful batteries.
"An alternator may be rated at 400 amps, but at idle speed you're only getting half of that," he says. "So where does all this extra power come from? You're depleting your batteries."
The real killer of electrical systems is when a driver shuts the truck off but doesn't turn loads off, says Bruce Purkey, President of Purkey's Electrical Consulting and the long-time Vice-chairman of TMC's electrical study group.
"Truck load haulers run their 14 hours and shut the truck off, and now they want to have air conditioning, their inverters, television, popcorn—they want the comforts of home," Purkey says. "And then when they do that—and 26 states have enacted anti-idling laws—they shut all the truck off so guess what has to take all the load? The batteries. You're going to shorten their life."
These increased loads are driving the need for more consistent power from reliable batteries. Technical product manager Kalyan Jana from the Reading, PA-based stored energy manufacturer Enersys says sturdy dual-purpose batteries like their Odysseys can reduce at least a few headaches for fleet managers.
"They can lead a more peaceful life—they won't have to worry as much about batteries," Jana chuckles. "For short-term, high-rate discharge for engine start application, it (can deliver) very high-energy pulses—at the same time, if you take it down to 80 percent of its capacity, provided you charge it properly, it can do that 400 times."
Dual purpose batteries have been in the consumer market for only the past four or five years, Jana says, so he ends up spending significant time educating buyers about the value of this more expensive option.
"You have to pay more up front, but think of the time you'll save because you don't have to do periodic maintenance checks, you don't have to go in and clean out the battery tray because there's no acid crud," he says. "You can lay these batteries on their sides—the battery tray will remain clean. All those maintenance costs are gone."
Jana says duals are growing in popularity among fleet managers because they have gotten sick and tired of dealing with battery problems.
"In Phoenix, we had a situation where some of the emergency vehicles were changing out batteries every 8-10 months, and when they switched to Odysseys, they have pretty much more than doubled their life," Jana says. "In the City of Seattle, they actually did, completely without our knowledge, they ran the Odyssey battery for about 18 months and called us and said, ‘We as a city are going to be switching 100 percent to Odyssey batteries.'"
Another advantage of duals for vehicles that must be kept on the road for long durations is preventing catastrophic failure—something Jana says is fairly common with traditional batteries.
"You could have a perfectly good start this morning, but this evening the battery could be dead," he says. "You would have to periodically go in and (check) the battery, and if you're not on the ball you could literally dry out the battery and cause major problems."
Jana says if drivers or technicians are paying attention, as the battery ages they will be able to tell if the quality of start is slowly degrading.
"Is it grinding the motor a little bit longer?" he says. "Is it becoming a little more difficult to start the engine in cold weather? The battery will give you enough advanced warning to say, ‘It's time to change the battery.'"
When there are starting issues, Purkey says many technicians simply install a battery with higher cranking capacity to try to alleviate the problem.
"They think that it is a capacity issue, which it is, but they fix the wrong capacity issue," he says. "They go to a high CCA battery that has more and thinner plates per element. They get more energy out, but this battery will not cycle nearly as well because of the thinner plates."
Installing a more powerful alternator to solve the problem is another common mistake, Purkey says, and avoids fixing the root cause.
"People don't understand the damage," he says. "They know they cycle and they know it's bad, so they buy a bigger amp alternator, but that doesn't fix the depth of (battery) discharge, it just helps recover faster. The damage is already done. But that discharge level is the critical factor, and they never change that. That's what's draining the battery."
Purkey says in the end, it's all about knowing the basics.
"With all the electronic stuff, it's still going to be fundamentals—if your electric system cannot perform and keep the voltage up, these systems will not run," he says. "It's a like a computer; it crashes."
CHECK THOSE CABLES
Perhaps the biggest basic mistake technicians make when attempting to diagnose electrical system problems is forgetting about the battery cables. When fleet managers thank Travis Hopkey and his colleagues at the Santa Fe Springs, CA-based truck parts supplier Phillips Industries for the company's new CLEAR-VU™ battery cables, he can in turn thank them. A few years ago, the idea came up in discussions with managers and was met with great response. Now, they are playing a key role in helping technicians check electrical systems more efficiently.
The problem with battery cables, Hopkey says, is what the technician doesn't see.
"Over time, in a corrosive environment with the magnesium chloride and calcium chloride they're putting on the roads in the wintertime, that stuff gets everywhere and finds its way into the tiniest of cracks to connectors that aren't properly sealed and it never really dries," Hopkey says. "If you've got an old cable, a bad cable, an improperly sealed cable; the stuff will find its way in there and will start wicking through the wire, so the battery cable starts to corrode and you just don't notice it."
Corroded wires strip needed electricity, and from there it does not take long to start affecting the entire electrical system.
"We've done some testing (in salt spray) where after 350 hours of voltage capacity the entire system drops down 12 percent, and after 750 hours it's more than 25 percent, which really puts some serious strain on alternators," Hopkey says. "If the system's not getting the proper charge at the proper voltage, bad things happen."
Clear—or more correctly—opaque cables are designed to eliminate potentially costly guesswork.
"The battery cable should be something you look at when you have a charging system problem and they can do it with a glance," he says. "A bad cable will cause a domino effect with the batteries, starter and alternator, and this is designed to give them a quick check before they do any other maintenance, because changing out a starter or alternator is hundreds of dollars of work. It's not just the cost of the parts, it's the downtime and the labor—if you see you've got a bad cable, that's a quick $25-$50 fix and the guy's back on the road."
While doing basic checks should be a starting point for any tech trying to diagnose an electrical problem, some new technology is also helping keep trucks on the road, and shop costs down. Corey Glassman, President of the Automotive Training Managers' Council and Automotive Program manager for the Everett, WA-based electronic test tool and software manufacturer Fluke Corporation, says new electronic devices like digital multi meters and voltmeters are becoming necessary tools for fleet technicians because electrical problems can often take some digging to find.
"You may have bad, crimped connections or poorly soldered connections, or perhaps (degraded) cables from flexing over time, because the diesels shake quite a lot," Glassman says. "That shaking it loosens connections or perhaps flexes cables where from the outside the cable might look OK, but internally, it may have a bunch of broken conductors and so that increases resistance. You can't tell just from looking at it."
When it comes to modern electronic equipment in a busy shop, Glassman says accuracy and durability are crucial.
"Our products are built for a rugged environment," he says. "If test leads, for instance, get caught in a fan belt or around a fan… we've had calls from customers that says the last thing they saw was the meter flinging across the shop and hit the concrete wall on the other side but it was still working. Repeatability and accuracy (are) important when you're trying to make numerous measurements because when you hook up to the circuit, if all other conditions are the same, your meter should continue to read the same values."
With the recent increase of in-truck electronics, there is more to maintaining these basic but critical electronic systems than ever before. How are technicians around the country keeping up with the changing technology?
In fact, they seem to be failing miserably—Purkey says in a recent TMC electric systems test, the average technician's score was a meager 37.6 percent.
How much do your techs know about electrical systems? Are they spending thousands of your dollars on what could be a 50-cent fix? Or worse?
Our October Heavy Duty story will further explore this misunderstood system, and experts will share horror stories about the sizeable knowledge and training gap that seems to be widening for many technicians.