Abstract: Various embodiments include a switching arrangement comprising: two processors; an OR gate; a first position feedback device; and a first switch. The a first switch. The OR gate output is connected to the first switch. The first processor is connected to the first input of the OR gate and the second processor is in operative communication with the OR gate via the second input of the OR gate; At least one of the processors sends a digital ON signal to the OR gate and the OR gate actuates the first switch on receipt thereof. The first position feedback device connects to both processors. The processors are interconnected and each programmed to: read a first position signal from the first position feedback device; send the first position signal to the other processor; compare the read signal to the received signal; and generate an error message if they do not match.

Abstract: Various embodiments include a switching arrangement comprising: two processors; an OR gate; a first position feedback device; and a first switch. The a first switch. The OR gate output is connected to the first switch. The first processor is connected to the first input of the OR gate and the second processor is in operative communication with the OR gate via the second input of the OR gate; At least one of the processors sends a digital ON signal to the OR gate and the OR gate actuates the first switch on receipt thereof. The first position feedback device connects to both processors. The processors are interconnected and each programmed to: read a first position signal from the first position feedback device; send the first position signal to the other processor; compare the read signal to the received signal; and generate an error message if they do not match.

Abstract: A monitoring device has a first flame detector, to receive a first batch of radiation, which is emitted by the first flame, a second flame detector, to receive a second batch of radiation, which is emitted by the second flame, a voltage supplying device to apply an alternating voltage with a first half wave and a second half wave to the two flame detectors and an evaluation circuit that is connected to the two flame detectors via a signal input. A first measurement signal that is present at the common signal input during the first half wave is indicative of the intensity of the first batch of radiation. A second measurement signal that is present at the common signal input during the second half wave is indicative of the intensity of the second batch of radiation. The evaluation circuit independently evaluates the first measurement signal and the second measurement signal.

Abstract: A monitoring device has a first flame detector, to receive a first batch of radiation, which is emitted by the first flame, a second flame detector, to receive a second batch of radiation, which is emitted by the second flame, a voltage supplying device to apply an alternating voltage with a first half wave and a second half wave to the two flame detectors and an evaluation circuit that is connected to the two flame detectors via a signal input. A first measurement signal that is present at the common signal input during the first half wave is indicative of the intensity of the first batch of radiation. A second measurement signal that is present at the common signal input during the second half wave is indicative of the intensity of the second batch of radiation. The evaluation circuit independently evaluates the first measurement signal and the second measurement signal.

Abstract: A signal isolator for providing at an output thereof representations of input currents from a source provided in an input conductor supported on a substrate having a bridge circuit suited for electrical connection to a source of electrical energization with a pair of series circuit members electrically connected in parallel with one another supported on a substrate with each series circuit member having a magnetoresistive member electrically connected in series with a current value controller, controlled at a controller terminal, at an output terminal of that controller. Each magnetoresistive members is electrically isolated from the input conductor and has a resistance versus applied external magnetic field characteristic that is substantially linear for at least relatively small externally applied magnetic fields.

Abstract: A self-cooled high-temperature fan apparatus for use in displacing high-temperature gases and atmospheres, such as the atmosphere within a high-temperature furnace. The preferred fan includes a frame supporting the fan. One or more bearings rotatably support a fan shaft. A fan element is supported by the fan shaft. Heat transfer through the fan and fan shaft is limited by an air-flow passageway and ports provided in the fan shaft and induction apparatus for inducing air flow through the passageway and ports as the fan shaft rotates. The fan apparatus is configured to limit heat transfer through the fan apparatus without the need for separate fan-cooling apparatus thereby preventing bearing damage and generally increasing the fan's operational life.