READ THE FINE PRINT: Cheap inverters may cost less, but they can cause expensive electrical problems.
VANCOUVER, B.C. – There’s a buzz in the air and it crackles with energy. AC power that is.
While power inverters have improved life on the road for drivers, they pose a potential predicament for fleet operators. Most fleet owners realize they can attract and retain drivers by allowing inverters on their trucks. At the same time, they realize that unauthorized or improper use of inverters can lead to potentially expensive electrical problems that can hurt the bottom line.
Inverters convert stored energy from a truck’s batteries into AC electrical power. They enable drivers to enjoy electrical conveniences such as laptop computers, entertainment systems and cooking appliances in the comfort of their cabs. Inverter/chargers have that same capability. But, they can also run the truck’s power loads off shore power while charging the vehicle’s batteries. They can even run space heaters or AC-powered HVAC systems to reduce or eliminate idling.
The benefits of driver comfort and idle reduction have sparked a surge in sales of inverters. Brian Lawrence, Xantrex’s OEM account manager says his company’s sales through truck OEMs (for factory-installed inverter/chargers) nearly doubled in 2005.
“We’re seeing excellent growth again this year,” he says. “It’s becoming an AC world for many drivers.”
While many fleets buy inverter/ chargers as a factory option on their new trucks, others install aftermarket inverters to their existing fleet.
“Inverters are one of the fastest growing add-ons in the trucking industry,” says Bruce Purkey of Rogers, Ark.-based Purkey’s Fleet Electric. Purkey has been assisting some of the area’s largest for-hire and private fleets with inverter installations for several years.
“The first thing I tell a fleet is you get what you pay for,” says Purkey. “You can buy very inexpensive inverters, but they won’t have any electronic protection and they may not protect your components. You have to be very careful. Inverters can have either a modified sine wave or a true sine wave. For example, I see more and more truck drivers who have sleep apnea and have to use CPAP machines. Many of these devices require a true sine wave AC output, something off-the-shelf truck stop inverters typically don’t have. If you don’t use a true sine wave inverter, the CPAP machine might not work properly and you’re putting your driver’s life at risk.”
Purkey says the many typical AC devices you use with an inverter are no less sensitive.
“If you’ve got a nice TV, you won’t get the full benefit and may even damage it with a bad inverter.”
In addition to considering a true sine-wave inverter over a modified sine-wave inverter, Purkey says another way to decode whether an inverter is worthy of purchase is by looking at where, in voltage, the inverter will shut off.
“A lot of times inverters will advertise they have shut-off protection. And they do, but it’s not what you think,” he says.
“They’ll often shut off at 10.5 volts which is done to protect the inverter’s own internal electronics. That shut-off level was not designed to protect your batteries – and you won’t be able to start a truck at 10.5 volts. You have to read the fine print about inverters. Don’t assume. Look for an inverter that will shut off at 11 to 12 volts.”
Smokey Point Distributing Inc. in Arlington, Wash., covers all 48 contiguous states and has outfitted its tractors with inverter/ chargers since 1994.
“We run 85 long-haul Peterbilt and Volvo tractors and each is equipped with a Xantrex inverter/ charger,” says John Berry, owner of Smokey Point Distributing. “Our drivers use laptop computers, coffee makers, cell phone chargers, microwaves, portable lighting – anything you’d plug in at home – in their trucks. Inverters allow our drivers to cook in the comforts of their own environment and reduce their constantly increasing expense of eating in the truck stops. It is in our best interest to assist our drivers in reducing their road expenses so that they can bring more of their hard earned paycheck home to their families.”
“With a continued need for additional drivers in the industry we feel a simple addition, such as an inverter, gives us another tool to attract good quality drivers for our trucks,” adds Dan Wirkkala, general manager for Smokey Point Distributing.
“We think the inverter makes a big difference in our driver turnover rate: it’s just 8%. When you consider our drivers are on the road two weeks at a time, we feel that’s phenomenal.”
Berry says inverter/chargers are a “must-have” item for his drivers, and, like Purkey, stresses the need to spec’ a high-quality product that can handle the electrical loads in today’s cab environment.
“I’d rather have our driver use one of our inverters than one they’d buy in a truck stop. I don’t want to run the risk of one of our trucks catching fire because an inverter is too small for the load or not properly installed,” says Berry.
“And if a driver leaves the lights on and the truck won’t start, he can plug 110-power into the inverter/charger and in a short amount of time, he’s back in business. Or if the driver notices the alternator running down, he can pull over or stay in a motel, charge the truck overnight and then drive to a repair shop the next morning to check on the alternator, which saves a roadside service call.”
“Inverters shouldn’t be an impulse buy,” adds Xantrex’s Lawrence.
“Read the spec’s, match the inverter’s power curve to your requirements, buy the right size for the load, and generate some buzz about driver comfort and less hours spent idling.”
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