Abstract: A fiber optic multiplexing controller for transmitting a separate original electrical signal to each of a plurality of signal receiving devices. Each separate original electrical signal originates from one or a plurality of signal sending units. A transmit section of the controller includes an encoder for encoding the separate original electrical signals into a single multiplexed electrical signal. The transmit section further includes a fiber optic transmitter for converting the multiplexed electrical signal to an optical signal. Thereafter, the optical signal is transmitted via fiber optics to a receive section of another identical controller. This receive section includes an optical receiver, provided for the purpose of receiving the transmitted optical signal and converting it to a multiplexed electrical signal. The multiplexed signal, whether electrical or optical, is made up of discrete portions. Each portion of the signal is devoted to a predetermined one of the separate original electrical signals.

Abstract: A hybrid switch (2) having a solid state circuit (2a) including a thyristor (SCR) for closing and reopening a supply circuit (S,4,6) to a load (L) and contacts including an isolating contact (S1) for connecting power to and disconnecting power from the solid state circuit (2a), a control contact (S2) for initiating turn-on and turn-off of the thyristor (SCR), and a bypass contact (S3) for shunting the solid state circuit (2a) after the load has been energized. A zero voltage crossover circuit (ZVC) allows turn-on of the thyristor (SCR) only when the A.C. supply voltage is below a preset value to avoid arcing at the contacts on closing. The inherent zero current crossing turn-off characteristic of the thyristor (SCR) avoids arcing at the contacts on opening.

Abstract: A resistance wire sensing overcurrent protection module (CSM) for an electrical supply circuit (SC) having a hot temperature sensing diode (32) mounted at the center portion (8c) of an M-shaped resistance wire (8) connected in the supply circuit and an ambient temperature sensing diode (20) mounted on a substrate (18) supported between the supply terminals (4a-b, 6a-b), both diodes being connected to respective pairs of terminals (12a-b, 10a-b) mounted on a header (18) along with the supply terminals. A cover (46) is mounted on the header and filled with glass micro-balloons (48) to isolate thermally the two diodes. A constant current circuit (49) supplies constant current to the two diodes which operate a differential amplifier (52) having an output proportional to the temperature difference as a measure of supply current. This output trips a Schmitt trigger comparator (54) when the supply current rises to an overload value.

Abstract: A dual roll vibratory compactor is provided with a single lever control for initiating travel in either direction and then starting the rotation of the eccentric weights to vibrate the rolls. Either or both rolls vibrate at low or high selected frequencies according to travel direction. A mode control switch is provided to provide the desired selections. A switch for reversing the selections is provided to maintain the same selections when the compactor is turned around.