Danisense announces 

For data acquisition users usually employ a variety of instruments, extending beyond traditional oscilloscopes. These instruments often lack a direct current sensor. Consequently, when users require a precision current sensor, they must also use a burden resistor to facilitate the connection. However, this often poses a significant challenge: users need to align the specifications of the current sensor with those of the burden resistor. The complexity of these specifications leaves considerable room for error.

The DS, DM, and DL series current transducers with voltage output from Danisense offer users highly reliable and accurate options for precise measurements of AC and DC currents from 55A up to 3000A. The products are ideal for a wide range of applications, particularly in harsh environments and high-temperature settings such as e-mobility, solar, and wind energy sectors. The high-temperature range capability of Danisense’s current transducers is especially beneficial in these fields. They offer a 1V or 10V BNC voltage output connection, a large aperture (up to 68mm) and very low linearity errors. All products are housed in full aluminum casings for superior EMI shielding and incorporate Danisense’s Fluxgate technology. This closed-loop compensated technology with fixed excitation frequency and second harmonic zero flux detection ensures best-in-class accuracy and stability.

For high-power current sensing needs up to 11kA, the DR series products with voltage output are ideally suited. The transducer core is optimized for high immunity against external magnetic fields. Additional features include a very large aperture of up to 150mm, very low linearity errors, a 3-pin XLR mini connector for voltage output, and an advanced sensor protection circuit (ASPC).

The post Voltage output current sensors measure up to 3000A AC-DC appeared first on Power Electronic Tips.

A temperature control device is used in applications where it’s necessary to regulate the temperature of a heated process. These devices are designed to maintain operation within a specified operating temperature range, usually controlling the operation of a heating element. Temperature controllers typically carry the full load current and are required to be ruggedly constructed.

A temperature sensor may or may not carry the full load current. These devices are placed so they can monitor the temperature at a critical location in the application. For example, they can turn on a light when an oven has reached its operating temperature. In other cases, they can be used to turn on a cooling fan when a higher-than-desired temperature has been reached. Temperature sensors have a reset switching temperature that’s typically 15 to 30 K below the initial switching temperature.

For example, a series of industrial temperature sensors with switching temperatures of 50 to 130 °C are available. The temperature is preset at the factory and can’t be changed in the field. Temperature sensing is implemented with a bimetal disk.

These industrial sensors are designed to protect compressors, pumps, and other machinery. They have a normally closed contact that opens when the temperature exceeds the preset level. When the temperature falls below the reset temperature, the contacts reclose. In addition, these temperature sensors are available with a second normally closed contact or with an internal Pt1000/Pt100 temperature measuring device (Figure 1).

Bimetallic temperature sensors are also available for use in general electronics, test equipment, and computer applications. Like industrial temperature sensors, these devices are based on a bimetal disk. They send an overtemperature signal to alert operators of abnormal operating conditions.

One of these temperature sensors is offered in a TO-220 package. It was developed primarily to support thermal management in electronic power converters. It’s suited for sensing the temperature of the surrounding air or on surfaces like heat sinks and circuit boards (Figure 2). This device has a switch capability of up to 0.5 A for 48 Vdc and is rated for up to 100,000 cycles at 5 Vdc and 0.010 A.

Over temperature protection

In addition to general thermal controls and sensors, over-temperature protection (OTP) is a key application for bimetallic thermal control devices. Like thermal controls, OPT devices typically carry the full electric load of the application. In some applications, the thermal control device is also used to provide over-temperature protection. There are three types of OTP devices:

Manual reset OTP devices are the thermal equivalent of an electric circuit breaker. Once they have tripped, they need to be manually reset to enable the system to return to operation. They are often found in consumer devices and white goods.

Non-reset OTP devices can provide an extra level of safety and control. They trip if the preset temperature is exceeded, but the user is not able to manually reset the device. Resetting requires the intervention of a service technician. Non-reset OTP devices are used when the root cause of a high-temperature condition needs to be determined and whether the application requires further maintenance or replacement.

Self-hold OTP devices require the user to disconnect the primary power source from the appliance to reset it. They generally require that the user wait for the system to cool sufficiently for the device to reset, enabling the appliance to return to service.

Thermal fuses

As the name implies, thermal fuses are the temperature equivalent of electric fuses that protect from over-current conditions. Thermal fuses, also called thermal links or thermal cut-outs (TCOs), are only good for one use and must be replaced to return the equipment to operation. They are often used as a backup to a primary shut-off device, as required by some safety agencies. They are used in systems where high-temperature conditions are indicative of serious safety concerns, like fire dangers.

Summary

Bimetallic thermal devices are highly adaptable and can provide monitoring, control, and protective functions. They are available in a variety of latching and non-latching configurations. These devices are suitable for harsh industrial environments, consumer appliances, general electronics, power conversion, and other applications.

References

Bimetal temperature switch For switching voltages up to 250 V, WIKA
Renewable Energy Applications Use CPI Thermals, Control Products, Inc.
Temperature Limiter Q (self holding), Limitor
Temperature switches, WIKA
The How-to Guide to Thermal Controls, Portage Electric Products
TO-220, Subminiature Bimetal Disc Thermostat, Sensata Technologies

The post What are the primary applications for bimetallic thermal control devices? appeared first on Power Electronic Tips.

This new SDLM-016-032-01-01 direct drive linear motor has a stroke length of 6.35 mm (0.25 in.) a continuous force rating of 1.14 N (4.11 oz.) and a peak force of 3.6 N (13 oz.) This non-commutated direct drive servo motor features: Quiet long life, plain linear bearings, an integrated internal 1.25-micron resolution quadrature optical encoder, and a non-rotating shaft.  Connections are easily made via a flex cable terminated in a 2-by-5 polarized connector.

These miniature linear servo motors are ideal for Medical devices (e.g. infusion pumps, prosthetic devices, and surgical robots), automotive and consumer products, aerospace (e.g. aircraft, drones, satellites, and rockets), robotics and industrial automation, and laboratory applications (e.g. microscope stages, pipetting, and sampling).

Direct coupling of the load or stage to the low inertia non-rotating shaft eliminates backlash and allows for high acceleration/deceleration.  Both ends of the actuator and shaft ends have threaded mounting holes for easy integration into new and existing applications.
The SDLM-016-032-01-01 Direct Drive Linear Actuator is also available with a matching servo controller. 

The post Direct drive linear servo motor integrates encoder and temperature sensor appeared first on Power Electronic Tips.