Giants of Generation

Wendling Quarries Opts for Portable Power to Keep Crushers and Other Equipment Humming.


By Mark S. Kuhar

The first production model of a 600-kW standby/550-kW prime-rated generator set powered by the new MTU Series 1600 diesel engine is undergoing rigorous field-testing at a mobile aggregate plant operated by Wendling Quarries.

As an operator of about 100 quarries in eastern Iowa and western Illinois, Wendling is using the generator set to power a variety of portable rock crushers, conveyors and bins that it moves from quarry to quarry to stockpile aggregate. The severe operating environment and high load factor of the quarry application made it the perfect choice for testing the limits of the new genset.

“We knew from the start that we wanted to place this prototype Series 1600 generator set in an aggregate quarry application,” said Michael Ware, sales manager for Interstate Power Systems, a distributor for MTU Onsite Energy. “Because of the remote location of most quarries, they rely on diesel generators for their prime power, which means that the generator gets a lot of use from day one.”

The Series 1600 engine is a completely new engine for MTU and is the smallest engine that the company produces. It has all the hallmarks of an MTU diesel engine: exceptional reliability, high power density and fuel efficiency. When the engine is combined with the completely new design of the generator set package, the result is a compact powerhouse that is ideal for emergency standby or prime power applications.

The generator set in the 600-kW standby/550-kW prime power node is based on the 12V configuration of the Series 1600 engine. “The engine’s load acceptance is exceptional,” said Neil Majeski, MTU program manager for the Series 1600 genset. “It is an incredibly stable engine that is very well built. The Series 1600 engines, from 12V to 6-cylinder inline, offer an advantage in covering power nodes that were previously sourced from two different engine manufacturers.”

The Series 1600 diesel generator set comes standard with many features that previously required custom ordering. Standard features include:

  • EPA Tier 2 certification.
  • Compliance to ISO 8528-5 testing for transient response at 85 percent load factor (as opposed to standard testing at 70 percent load factor).
  • NFPA 110 one-step rated load acceptance (one-step 100 percent block load).
  • Digital control panels that are UL-recognized.
The series 1600 generator set works perfect for a portable plant.
The series 1600 generator set works perfect for a portable plant.


Prime Power
“We’re in the rock, quarry and sand business, and we have multiple mobile and stationary crews,” said Hollis Emerson, equipment manager for Wendling Quarries. “A mobile crew has a primary crusher, a secondary crusher, screen plant, bins, loaders, generators and trucks. Since they move every three weeks to a couple of months, we thought this Series 1600 generator set would work well with a portable crew as it moved around to different locations. We started using it in the Cedar Rapids, Iowa area at one of our concrete recycling yards, where old concrete is broken up and crushed for high-quality aggregate. It’s one of the most power-intensive activities in a quarry.”

Most of Wendling’s operations quarry limestone, and the product is used in a wide variety of construction applications, including concrete, roads, highway shoulders, asphalt and sub-base.

At each quarry site, aggregate of various sizes is quarried, crushed, screened and stockpiled for use during the year. The amount of aggregate stored at each site varies from 60,000 tons to several hundred thousand tons. Once there is a sufficient amount of rock stockpiled, the portable plant is moved to the next quarry.

“About half of our crushers are diesel-powered, and half are electric-powered,” said Emerson. “That gives us real operating flexibility. If we’re at one of our quarries with a highline, we prefer to run on electricity from the utility. When we’re at a remote rural site – which describes most of them – we either produce electricity with the
generator or run the diesel-engine-powered equipment. Sometimes we do both, depending on the mix of equipment.”

The mobile plant used in the test has a main crusher that is powered by its own diesel engine, and the MTU generator set is being used to power electric motors in the portable plant up to 60 hp in size. At any one time, the total load on the generator set is estimated to be about 375 kW, and it operates about 10 hours a day, five days a week.

Emerson said that having both diesel- and electric-powered equipment provides flexibility and also prevents downtime due to equipment problems. “We have six portable aggregate plants like the one under test, and when we have both diesel equipment and electric equipment, we can mix and match depending on our needs. If an electrical crusher or conveyor breaks down, we can quickly move in a substitute because all of our electrical connections are interchangeable. Some of our electric crushers have 300-hp motors on them,” he said.

Facilitating Connections
To facilitate electrical connections, the outlet box on the Series 1600 genset has been designed by MTU to incorporate the breaker and control panels in one streamlined package. Its design allows for the flexibility to switch the control panels and breakers to the right or left depending on the need, and allows the mainline circuit breaker to be installed in a compartment on the right or left side depending on customer needs.

The outlet box can accommodate multiple mainline circuit breakers, utilizing both compartments. This is a standard design feature that previously would have required custom engineering.

The Series 1600 generator set also has an improved electrical stub-up compared to similar gensets powered by other engine types. The new design allows ample room for connecting cables in the stub-up area, thus making installation easier.

Another design advantage is in the mounting of the outlet box. Whereas previous generator set designs mounted the outlet box to the barrel of the alternator, the Series 1600 outlet box is mounted directly to the base of the genset. This significantly reduces the amount of vibration to which the outlet box is subjected, which in turn has a positive effect on the life of the electrical system.

To protect the test unit from dust and weather at the quarry site, the generator set is housed in a 22-ft. ISO-style container that was provided by MTU Onsite Energy. The container was then mounted on a lowboy trailer with a triple axle at one end so a bulldozer could move it around the quarry as needed. A 550-gal. fuel tank was added to the trailer that the crew can refill as needed from a tank truck. Periodic maintenance on the generator set is being performed by Interstate Power Systems.

Every 250 hours of operation, the MTU distributor changes the oil and filter and performs a general inspection. Maintenance done by Wendling’s employees includes changing the fuel and air filters on an as-needed basis.

As one of the largest aggregate companies in the Midwest, Wendling has run tests for other industrial manufacturers and views this arrangement as beneficial. “We’ve had a very good working relationship with the dealers and factories. Over the years, we’ve come to the conclusion that if doing a field test works for us and works for them, too, we’re happy to partner,” said Emerson.

According to Ware, there were many aggregate quarries that could have provided the operating hours necessary for the field test, but it was Wendling’s attention to detail and experience field-testing engines that made it the perfect fit for this new generator set.

“We have an excellent working relationship with Wendling, and they have a commitment to detail that will ensure we get an accurate reflection of the unit’s performance,” said Ware. “They have field-tested engines before, so they know how the process works. This also provides us with a great opportunity to show them what MTU Onsite Energy has to offer.” 

Operational Reliability

Wendling Quarries, Cedar Rapids, Iowa, is participating in rigorous field-testing at one of its mobile aggregate plants using Series 1600 generator sets to power a variety of portable rock crushers, conveyors and bins that it moves from quarry to quarry to stockpile aggregate.

At any one time, the total load on the generator set is estimated to be about 375 kW, and it operates about 10 hours a day, five days a week.

Series 1600 generator sets are based on the 12V configuration of the Series 1600 engine and cover the 550 kW to 600 kW standby-rated power nodes. Other configurations of the engine series will include 10V and 6-cylinder inline and cover power nodes down to 250 kW.

MTU Onsite Energy is a brand of Rolls-Royce Power Systems AG. It provides diesel and gas-based power system solutions: from mission-critical to standby power to continuous power, heating and cooling. MTU Onsite Energy power systems are based on diesel engines with up to 3,400 kW power output, gas engines up to 2,150 kW and gas turbines up to 50,000 kW.

Related posts