Practical Instrumentation Course

Non-intrusive methods for measuring current in instrumented loops: clamp-on and diode test

A better way to measure a 4-20mA signal without interrupting the loop is to do so magnetically, using a clamp-on milliammeter (sometimes called a clamp meter). Modern sensors

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Electric Motor Control Course

DC injection braking in three-phase motors

This braking procedure is achieved by disconnecting the motor from the AC power supply and connecting two terminals of its stator to a DC power source. These remain valid.

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Electric Motor Control Course

Countercurrent Braking and DC Injection

BRAKE INCORPORATED IN THE MOTOR In this special type of motor, the rotor, which is short-circuited, is slightly truncated conical and is displaced a little with respect to the stator core,

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Practical Instrumentation Course

Troubleshooting control loops: safety considerations for current measurement

A fundamental principle in solving problems in instrumentation systems is that all instruments have at least one input and at least one output, and that the

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Practical Instrumentation Course

2-wire transmitters: voltage always accompanied by current 4-20mA!!!

It is possible to combine electrical power and analog communication over the same pair of wires using 4-20mA DC, if we design the transmitter to be "loop powered" or "powered by"

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Practical Instrumentation Course

Troubleshooting current loops with voltage measurements: when all we have is a voltmeter

If we cannot interrupt the loop due to operational reasons, and no component (diode) is pre-installed in the loop, and furthermore, if we do not have an instrument to

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Variable Speed Drives Course

Speed and Current Transducers for Motors

Transducers are devices that change one physical quantity into another; that is, • The physical quantity of angular velocity can be changed into the physical quantity of voltage. • Quantity

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News and Current Affairs

Siemens: Sinamics DC Master (DCM) New DC drive

The rated DC current of the drives ranges from 15 to 3000 A and can be increased by connecting several units in parallel. Sinamics DCM integrates this into a single enclosure.

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