Electronic controls are attractive to designers and equipment operators, but they also appeal to those who have to repair equipment. Eliminating hydraulic hoses opens up a lot of space, while adding digital controls makes it easier to troubleshoot many problems.
Operators in the field may decry the move to electronics, which makes it more difficult to make minor mechanical repairs without calling maintenance experts. But modern designs are making life easier for those experts.
“Electrohydraulics also allows diagnostic equipment to be used in servicing the equipment by recording fault codes to help identify and resolve issues faster,” said John Mount, System Senior Design Engineering Specialist, Caterpillar.
Replacing mechanical controls with controllers and networks also saves a lot of space while adding flexibility. Electrohydraulic systems may be more complex technologically, but they simplify the hose layout by reducing the number of pilot lines, which “reduces potential leak points and improves accessibility, making tilt cabs and servicing machines much easier,” said Doug Koehler, Steering/Implement/Brake System Engineering Manager, Cat.
System suppliers also note that combining networks and distributed controls can reduce the amount of wiring in a vehicle. Eliminating wiring, like eliminating hoses, eliminates many of the potential failure points.
“There’s also a savings in the long run when a technician in the field doesn’t have to chase down a wiring problem when there are 50 to 100 wires,” said Joseph Maher, Business & Product Development Vice President at Hydro Electronic Devices Inc.
Electrohydraulic systems can also prevent some of the catastrophes that can cause major damage to vehicles. Sensors in the seat can tell when operators leave, and they can send a message over the network to alert control modules.“Our operator-presence system automatically sets the parking brake and neutralizes hydraulic functions if the operator leaves the cab without setting the brake,” said Jennifer Rojas, Six Sigma Black Belt at Cat.