Sentinel Announces Major Design Advancement in RFU Technology

Sentinel, a Beier Radio company, has designed and manufactured a new Rudder Feedback Unit (RFU) with many innovative features long sought by the marine industry. Unlike other RFU’s on the market, Sentinel’s new RFU has watertight components and connections that can be flooded in up to one meter of water for a 24-hour period and still provide accurate positioning for control systems.

The unit provides precise rudder position feedback via four non-contact inductive resonance encoders with IP67/IP69K degree of protection. The encoders are mounted in a custom-designed RFU enclosure constructed of 3/8” nominal impact, highly corrosion resistant Vintec I ® PVC to IP68 standards. The RFU utilizes IP68-rated proximity sensing limit switches providing accurate, non-contact electrical travel limits.

“Our engineers have designed an RFU that meets the environmental demands of today’s inland and offshore vessels,” says David Lirette, Vice President of Manufacturing for Sentinel Control Division of Beier Radio. “Where other units in the past have been completely damaged by water intrusion, this unit can survive complete submersion and still provide accurate positioning to the control system.”

“RFU design has not changed in more than 30 years, and Sentinel recognized the industry’s need for a more reliable steering system. We spent two years designing and testing multiple prototypes to make a feedback unit that eliminates issues with previous technology, and Sentinel is pleased to now offer this innovative new design to the marine industry,” Sentinel Design Engineer James Cole.

IP67-rated external connectors match factory-supplied cables that are available in five pre-cut lengths, and drilling is not required, reducing installation time. The stainless steel linkage shaft is adjustable from 3” to 15-5/8” length from center of rotation. The RFU has no internal wiring, which eliminates wiring errors and faults. The inductive resonance encoders feature voltage and current outputs that can interface to the majority of steering and dynamic positioning systems available on the market today and are programmable to provide maximum resolution within any span of rotation.

The RFU is designed and manufactured by Sentinel at Beier Radio’s 20-acre facility in Gray, La. Sentinel is an original equipment manufacturer of high quality control and instrumentation products and systems and is an affiliate of Beier Integrated Systems and The Marine Training Institute within the Beier Radio family of companies.

It is not the intent of Sentinel Control to install this unit in a tank or compartment designed to be flooded, however, if the steering compartment becomes flooded, this unit is designed to operate submerged and provide accurate position information allowing the vessel to be maneuvered to a safe area for repair.