A electronic ac drives / variable frequency drives (VFD) low/ medium voltage is a system for controlling the rotational speed of an alternating current (AC) electric motor by controlling the frequency of the electrical power supplied to the motor. A variable frequency drives is a specific type of adjustable-speed drive. variable frequency drives are also known as adjustable-frequency drives (AFD), variable-speed drives (VSD), AC drives, microdrives or inverter drives. Since the voltage is varied along with frequency, these electronic ac drives are sometimes also called VVVF (variable voltage variable frequency) drives.

A Programmable Logic Controller (PLC), or programmable controller is a digital computer used for automation of industrial processes, such as control of machinery on factory assembly lines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non-volatile memory. A programmable logic controller (PLC) is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result.

AC Servo systems are typically permanent magnet synchronous motors that often have low torque-to-inertia ratios for high acceleration ratings. AC servo motors have an output shaft that can be positioned by sending a coded signal to the motor. As the input to the motor changes, the angular position of the output shaft changes as well. Generally, AC servo motors are small but powerful for their size and easy to control. Induction and gearmotor types are some common forms of AC servo motors.

The PCC could be defined by the engineer at any point in the system (such as at an MCC bus) but it is usually understood to be the point where the customer connects to the utility (unless otherwise stated). Even though engineers are free to apply IEEE 519 at other points in the system to require equipment compliance, the standard is still intended to be a system specification. European IEC 61800 specifications, on the other hand, are equipment (rather than system), based.

Panel PC 300 makes a Panel 900 an embedded PC based on a 500-MHz processor. It has 256 Mbytes of SDRAM, Ethernet 10/100, a serial interface, and support for USB 2.0 interfaces. The 900 handles applications that do not require the computing power of an APC620. It comes in 10.4-in. VGA, 12.1-in. SVGA, 15-in. XGA, or 17/19-in. SXGA resolutions, with touch-screens and keys. The 300 does not need a fan, and used with CompactFlash cards, there are no rotating parts.

Process Plant Automation
Process control is used extensively in oil refining, chemical processing, electrical generation and the food and beverage industries where the creation of a product is based on a continuous series of processes being applied to raw materials. Such systems typically deal with analog signals from sensors and meters that are transmitted to specialized computers which cause the temperature, pressure and flow to be continually adjusted (see DCS and PAC). Process control makes extensive use of analog/digital and digital/analog conversion.

SCADA

A SCADA system includes input/output signal hardware, controllers, HMI, networks, communication, database and software. It mainly comes in the branch of Instrumentation Engineering. The term SCADA usually refers to a central system that monitors and controls a complete site or a system spread out over a long distance (kilometres/miles). The bulk of the site control is actually performed automatically by a Remote Terminal Unit (RTU) or by a Programmable Logic Controller (PLC). Host control functions are almost always restricted to basic site over-ride or supervisory level capability. For example, a PLC may control the flow of cooling water through part of an industrial process, but the SCADA system may allow an operator to change the control set point for the flow, and will allow any alarm conditions such as loss of flow or high temperature to be recorded and displayed. The feedback control loop is closed through the RTU or PLC; the SCADA system monitors the overall performance of that loop.

Trapped passengers in an elevator in case of a power outrage are rescued by the Auto Rescue Devices (ARD). In the event of power failure during normal operation, an elevator may stop in between floors. Our electronically operated ARD senses the position of the car struck in between floors and moves it to the nearest floor in the most economical direction and completes the rescue by opening the doors at the floor level.

The eddy current drives drives are suitable for any general purpose application that involves a AC motor, has full of operation functions. Built-in variable digital/analog input functions to suit a wide array of needs.

Simple eddy current adjustable dynamometer is a totally new concept in dynamic load system for accurate testing applications of all type of electric motors, engines and other rotating machineries, Some of the features of our products are - excellent stability, better accuracy, small and compact, wide range of power and speed, excellent mechanical stability, very little down time and maintenance and low noise-levels.

 We are offering the following range of Control Relays:

Phase Control Relays: (MWS, MWS2, MWG, MWU, MWA, MWUA, HWUA, H3US, H3USN, M3US):

• Presence and regeneration, phase sequence, phase balance and level of asymmetry (or balance),
• adjustment of voltage thresholds

Voltage Control Relays: (MUS, MUSF, HUL, HUH):

• Overvoltage, Undervoltage control
• Self Powered Versions

Current Control Relays (MIC, HIL, HIH):

• Overcurrent and undercurrent control
• Version with built-in current transformer

Frequency Control Relays: (HHZ):

• Overfrequency and underfrequency control of the 50 or 60 Hz AC signal

Pump Control Relays (HPC):

• Control of sinhgle-phase or 3-phase pumps
• Dry run and overload protection
• 3-phase control

Level Control Relays (HNM, MNS, HNE):

• Automation of filling and emptying cycles
• High or low level information
• Check for presence of a conductive or non-conductive liquid by temperature probe or discrete sensor

Speed Control Relays (HSV):

• Monitoring of pulse rates
• Overspeed and underspeed control, rotation or movement control

Life Temperature Control Relays (HT81, HT81-2, HWT81):

• Temperature monitoring in machine rooms and lift pulley rooms in accordance with standard EN 81
• Version with built-in phase control
• Phase failure with regeneration upto 70%

Phase and Temperature Control Relays (HWTM, HWTM2):

• 3-phase network control
• Motor temperature control with PTC probe test and memory function on temperature control