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Virtual slip rings transmit power or signals across air gaps

Virtual slip rings transmit power or signals across air gaps

Coupling units transmit electircal power, control signals, or both across air gaps between stationary and rotating machine elements.

Power Coupling Units (PCUs) can inductively transfer dc signals across air gaps to interface with solenoids, digital or analog sensors, switches, relays, and actuators on rotary indexing tables or moving equipment. Sensor Coupling Units (SCUs) take it a step further — transferring power and data simultaneously to rotating or moving sensors. Both units are part of a series of contactless coupling products manufactured by MESA Systems Co., Stonington, CT.

The PCU consists of transmitter and receiver modules, each housed in a compact cylindrical industrial case. Sizes range from about 10 mm to 1 m in diameter. When positioned opposite each other, up to 10 mm apart, any transmitter module will inductively transfer 24-V dc signals across the gap to any receiver module. Power is rated to 350 W, whereas 5 to 50 is more typical.

Communications can be formatted serially, as a databus or simple binary signals. Systems can be simple — transmitting only power — or complex, having multiple air-gaps, full duplex interface or CAN bus coupling.

Inductively coupled devices operate reliably in demanding environments, including under water, in vacuum chambers, ultra clean environments, covered with grease or mud and at high rotational speed.

In both units, LEDs indicate status, input sides are polarity-protected, output sides are short-circuit-proof, and the system is protected against overvoltage. With no moving parts or mechanical connectors to wear out, the PCU and the SCU couplers require no maintenance.


For more information, call MESA Systems at 508.655.6372 or visit

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