Ultraviolet (UV) lamps are used commonly to disinfect water by killing bacteria. High Intensity Infra Red (IR) lamps are used in a variety of industrial processes to provide heat both for drying and curing processes. Correct operation is very important and can be determined by measuring current draw. Using an NK Technologies’ Current Operated Switch provides simple and quick verification. The on/off contacts of the switch may be used to simply indicate status to an operator using a lamp or wired to the input of a PLC preprogrammed with the necessary corrective action. Alternatively, NK’s Current Transducers may be used to provide an accurate measurement of the current draw by a UV, IR or other light source.
High technology lamps have been developed for a variety of specialized industrial and commercial applications. These lamps are expensive and their useful life should be maximized. Installing an NK Technologies’ Current Transducer to measure the current draw of a lamp provides the information to determine the lamp’s condition by comparison to known characteristics. Intelligent control devices, like PLCs, are programmed to adjust the applied voltage or current to optimize the life of the lamp.
The simple addition of an NK Technologies’ Current Operated Switch in a lighting circuit provides an isolated on/off signal to either a relay to automatically switch to a back-up lamp or signal a PLC to indicate lamp failure. The split-core model is designed for quick and simple installation for existing installations and the solid-core device provides a compact solution for new installations.
Heat trace cable is used to keep pipes or their contents from freezing, or to keep the contents at a constant temperature while being transferred from one location to another. The most common type of heat trace cable is the self-regulating type. Self regulating cable contains two conductors and is usually physically attached to the pipe and is therefore is subject to mechanical damage. NK Technologies’ Ground Fault Sensor are frequently installed to monitor heat trace circuits and systems. When a ground fault is detected, a circuit interruption device, like a contactor or shunt-trip circuit breaker, is used to automatically disconnect the faulty circuit. In many situations NEC and/or local electrical codes require the installation of ground fault interruption devices. However ground fault sensors are commonly installed, even if not required by code, in order to monitor the condition of the heat trace cable and installation and maintain safety. Faulty circuits can be identified and then repaired or replaced at a convenient time.
Industrial electrical heaters are prone to ground leakage due to the breakdown or contamination of insulators. The use of NK Technologies’ Ground Fault Sensors enables early detection of leakage Currents as small as 5mA. The on/off output of the sensor can be used to trigger a circuit interruption device (for example a shunt-trip breaker) or a monitoring device like a PLC to determine the required action. Latching and auto-reset models are available in both normally energized and normally de-energized configurations suitable for most applications.
As an electric heating element ages, its resistance also changes. Many high technology and extreme temperature applications employ exotic and expensive elements. Where the value of the products or materials being heated is high, the failure of a heater or heating element has a financial impact resulting from either reduced quality or scrapped materials. By measuring the current drawn by the element using an NK Technologies’ Current Transducer the resistance of the element can be determined and compared against a known ageing characteristic. When the element reaches a predetermined state it can be replaced prior to failure i.e. predictive maintenance. NK Technologies’ Current Transducers are used in conjunction with intelligent PLC systems when high power SCRs (also known as thyristors) or triacs are installed.
Vacuum pumps are used in a variety of applications in the semiconductor industry, heat treatment, plastics and packaging industries. By adding an NK Technologies’ Current Transducer over the lead feeding a vacuum pump, it can easily be determined when all the air has been removed from a vessel or envelope. The analog output can signal the vacuum or equipment controller that it is time for the next step in the process. In the case of an automated packaging machine, a drop in current will signal that the package is ready for sealing.
An NK Technologies’ Ground Fault Sensor installed on a submersible pump motor provides an easy to install replacement or addition to moisture sensors housed in the motor casing. Unlike moisture sensors that have to be wired back to the motor control center, the GF sensor is installed in the motor control center. By detecting the ground fault current resulting from moisture ingress or other potentially dangerous condition remedial action can be taken prior to catastrophic failure. Either the pump can be replaced at the next convenient time or switched off and a back-up pump started.
NK Technologies’ Current Transducers are used to monitor motor current and therefore motor load. The output from the transducer may be fed to an analog or digital indicator or a Programmable Logic Controller (PLC) for more sophisticated monitoring and control.
NK Technologies’ Power Transducers provide load monitoring in more critical applications where the addition of voltage measurement and the determination of the phase relationship between current and voltage (power factor) provides more control.
NK Technologies’ Ground Fault Sensors keep the pumps safe by measuring ground leakage currents as low as 5mA. This also provides an alternative to moisture sensors used with submersible pump motors.
Also see these other articles:
Pump Jam & Suction Loss
Moisture Ingress on a Submersible Pump Motor
The auxiliary contacts in a motor starter are commonly used to indicate when the motor is running. However, auxiliary contacts only indicate the position of the contactor, not the actual load status. If a downstream disconnect is open (for example, for maintenance) or the contact fails (either sticks or dirt build-up) there can be serious consequences.
At a large fish farm, failed aerator pumps resulted in massive stock losses. Because the auxiliary contacts remained closed when the pump failed, the alarm was never activated, the back-up pumps were not switched on and the fish suffocated due to lack of oxygen. Now NK Technologies’ Current Operated Switches have been installed to provide an alarm signal and a signal to automatically switch over to the back-up aerator pumps.