As the economy and the rental industry both slow from the frenzied pace each enjoyed throughout recent years, rental centers will continue to engage in more selective, cautious equipment acquisition decisions. While product value and return on investment have always been key purchase considerations, rental centers throughout the country must place an even greater focus on such issues today.
Consequently, equipment manufacturers must also make changes. Regardless of product type, manufacturers must recognize their customers' needs and provide equipment that meets customer demands. Light tower manufacturers are no exception. Resisting the urge to cut corners, light tower manufacturers continue to enhance products, delivering portable light sources that are brighter, more efficient and easier to use.
When selecting light towers, rental centers should examine several key factors, such as performance and durability, machine size, ease of operation, noise contamination and machine design. Considering these factors ensures the addition of a piece of equipment that will be productive and profitable for years to come.
Performance and durability
For rental centers and rental customers, fixture performance should be the single greatest factor in portable light tower selection decision. The reason is obvious. A more efficient lamp fixture lights a greater area. The result is fewer light towers on the job site and savings for the rental customer.
A portable light tower's light output is controlled by its lamp and fixture. Traditionally, portable light towers have had commercial-grade, co-axial light fixtures. Because of its design, the majority of a lamp's light from a co-axial fixture is reflected rather than direct light.
Light tower manufacturers utilizing 1,000-watt lamps and co-axial fixtures may claim they provide 110,000 lumens per lamp, but this claim is misleading. A 1,000-watt metal halide lamp will only provide 110,000 lumens if the light is pure, in other words, not reflected. When placed in a co-axial fixture, most of a lamp's light is reflected off the fixture surface, and therefore, the lamp's light output is well below its 110,000-lumen capability.
Independent testing has shown that fixtures offering the purest, most direct, nonreflective light output, such as parallel lamp fixtures, provide the most usable lumens directly to the job site and are the most efficient. Parallel lamp fixtures with horizontally mounted lamps provide far superior lumen output to lamps mounted in traditional co-axial fixtures.
Additionally, parallel lamp fixtures' oval design delivers an even distribution of light over the entire work area. Co-axial fixtures typically produce spots of light, referred to as hot spots, that are much brighter than the rest of the illuminated area.
Perhaps the biggest maintenance concern on light towers is fixture durability. It can cost up to $150 to $200 to replace a light fixture. Rental centers can spend thousands of dollars on lamp and fixture breakage and replacement — which, typically, is then passed on to the customer. The oval design of most parallel lamp fixtures is more rugged than thin, round co-axial fixtures, enhancing parallel fixtures' durability and extending operating life.
Parallel lamp fixture designs provide added protection to lamps during towing and while on the job site. With a flexible yoke design and superior lamp support within the fixture housing, lamp breakage is drastically reduced. Light towers with parallel fixtures may be transported with the fixtures installed, reducing set-up time and damage during travel, removal and replacement. In fact, light towers are often shipped directly from the factory to the job site. It's a significant savings of labor and time for both the rental center and the end user.
To ensure optimum light is directed to each job, users should be able to tilt a light tower's fixtures at any angle without coming into contact with other fixtures or mounting bars. Many light towers utilizing co-axial fixtures do not allow such movement, and costly fixture and lamp breakage is often the result.
Portable light tower manufacturers have realized that in most situations rental centers and rental customers prefer a heavy-duty, yet compact, light tower. Compact light towers offer many significant advantages over traditional, large, wide-stance, somewhat overbuilt light towers.
First, compact light towers can be shipped side by side on a delivery truck, resulting in significant savings in transportation costs both from the factory to the rental center and from the rental center to the customer. For rental centers, a smaller light tower takes up less storage space on a rental yard, and, for the end user, a narrower light tower saves valuable space on the job site. This proves especially effective on such job sites as a bridge deck, where the machine's compact design could possibly allow one lane of traffic to remain open while work continues.
A more compact light tower also has a lighter tongue weight, leading to better maneuverability. Many of today's compact light towers may be easily maneuvered around the job site by hand, rather than with a vehicle, allowing more precise placement and added mobility.
While compact light towers are typically about a foot narrower than traditional models, design should still be heavy-duty and able to sustain significant wind gusts.
Ease of operation
Because of demands of rental centers and end-users, portable light towers are becoming more customer-friendly to operate. Many light towers offer a mechanism that locks the tower down and prevents it from inadvertently extending when towing.
Another example is the increased use of latches. In the past, light towers used pins, which were troublesome and frequently got lost. Self-locking stabilizers and a captive latch on the tower support have eliminated the need for pins, resulting in a simpler, more reliable and safer basic unit.
Many light towers feature generators allowing the units to power auxiliary equipment. Generators should offer at least 6 kilowatts of power in order to give rental customers the flexibility they need to power small tools on the job site. Some light tower manufacturers are offering larger generator options, such as 8-, 15- and 20-kilowatt models. These more powerful generators dramatically increase a light tower's versatility on the job site.
Job site and operator safety, as well as the emergence of the special event market, have made noise contamination a significant consideration for rental centers and their customers. Light tower manufacturers have minimized vibration noise with heavy-duty enclosures and well-mounted engines, and many light towers offer sound attenuation packages to further reduce noise. A light tower's noise level should be no more than 65 dba.
Fuel capacity is another important feature of a portable light tower. A minimum fuel tank capacity of 30 gallons, which provides more than 60 hours of continuous operation, is best for most jobs. Molded polyethylene fuel tanks reduce the risk from rust and corrosion associated with metal.
Rental centers expect to keep a light tower in its fleet for a minimum of three to five years. And rental centers can rest assured because portable light towers constructed with dent- and rust-resistant molded fenders and protective enclosures constructed of 10- to 12-gauge sheet metal will help withstand the rigors of continual use and help ensure a rental center's return on its investment.
Light tower manufacturers are continuing to bring more efficient, productive, versatile and profitable machines to market — units from which rental centers can easily see profits. In order to reap these profits, however, it is essential for rental centers to be aware of the new and innovative products available to them, whether it is a light tower or any other product that can meet the needs of its customers.
Jerry Greenquist is vice president, sales and marketing for Allmand Bros. Inc., Holdrege, Neb.