Quality of the Power delivered to an electrical consumer is important because it has significant impact on
Energy consumption/ cost
System performance & efficiency
Equipment life time
Aaging and performance of the equipment in a facility are influenced by many factors :
Power disturbances, caused by external factors (lightning strikes, faulty power lines, etc.)or internal factors (faulty equipment, electric discharge etc.), degrade the equipment over time, to eventual complete failure.
High-magnitude harmonic voltages are especially detrimental causing:
Malfunction of control devices, signaling systems, protective relays,
Extra losses in capacitors, transformers, and rotating machines,
Increased noise emitted by motors,
Voltage amplification even at a remote point from the distorting load.
Overloaded circuits heat up the wires and cables, decreasing efficiency and performance, and leading to damaged conductors, defective equimpent, and even fire
Excessive reactive loads drop eficiency and raise power bills
Unbalanced loads damage motors and equipment, decrease their efficiency and effective life span
THE ROLE OF A PQ SENSOR
Factories and facilities have been working for years without a power quality sensor. So, what would a supervisory device do in the first place?
Facilities without a PQ sensor are used to expending on costly unplanned down-times, expensive repair bills, derated apparatus, and shortened eqiuipment life. Besides, they live with electricity initiated fire hazard not knowing the status of their electrical system.
Electrical equipment like Pumps, compressors, cranes, blowers, mills, crashers, grinders, extruders, conveyers, lathes, rectifiers, computers, UPS systems, etc. display a normal electrical pattern indicating they are in a good condition. When something is starting to go wrong, it is first reflected on the pattern. so by keeping an eye on the electrical behavior of the equipment, it is possible to detect and fix impending problems ahead of time, i.e. before they turn into serious expensive and hazardous defects.
What can go wrong?
Overloads due to ware or improper wiring
Winding impedance increase
Conductors heated above their rating
Incoming disturbances such as lightning, grid induced harmonics,
Watching the power quality in realtime, a PQ sensor helps protect assets, improve system performance, and reduce energy costs.
And when it comes to chanes and modifications like system expansion, upgrade, adding or changing apparatus, and so forth, it is important to make sure that it is directed in a safe and secure manner. That in turn requires first to get an actual picture of the existing system so that the effect of modifications on the system can be foreseen and accounted for. To get a picture of the existing system, a comprehensive load study is required. A comprehensive and precise load study report ideally includes the actual load profiles on all the important portions of a facility during the hours of day (and night), days of month, and months of year. Such a comnprehensive report enables the engineers and managers to make optimum decisions.
NTPM Power Quality Sensors measure /calculate more than 100 electrical parameters, including:
RMS Voltages: Phase & line (Min, Max, Avg.)
RMS Currents:Phase & line (Min, Max, Avg.)
Frequency: (Min, Max, Avg.)
Power factor: Per phase & total (Min, Max, Avg.)
Power:Active, Reactive and Apparent , per phase & Total (Min, Max, Avg.)
Energy:Active & Reactive (four quadrant)
Maximum demand:Per phase & total (15, 30, 60 min. intervals configurable )
Harmonic content :1st to 31st,V & I, per phase
THD (Total Harmonic Distortion): For V & I, per phase (Min, Max, Avg.)
Temperature:Device operating temperature
Tariffs:Active & Reactive Energy (four definable)
NTPM meter/ recorders are, in a standard configuration, equipped with either Ethernet interface. This enables extremely easy integration in existing network infrastructure. In addition, a built in Web support provides an easy way to interact with a device from any web en
abled front end, including tablets and mobile phones.Any HTML5 based web browser is the only external software needed to configure and operate NTPM.
The built in web interface allows instant access to real-time as well as historical measurements, which are displayed in an attractive, dashboard like, user interface.It is possible to easily configure graphs to compare and display only desired information.
Easy web based configuration, with no additional tools or external software. All configuration options are available through a set of WEB links
made accesible only to authorized users. Two classes of user logins are available: administrators, with full access to measured data as well as device configuration , and operators with access to measurements only.
Two N.O. (Normally Open) contacts on NTPM may be controlled either directly over the Ethernet link, or by a Rule Enginegeneratedprogram. The output contacts can be used to Open/Close a circuit, Start/Stop an audible alarms or a flash light, etc.
Each NTPM is equipped with a solid state memory and supports long term storage of measured and calculated parameters.
A history of all measured data may be stored with 1-second resolution for a one month, while if you choose the most important parameters to be stored every hour, you have enough space for 10 years.
Read and write operations are optimized to ensure long memory life.
EMBEDDED PROGRAMMING TOOL
Thanks to the built in rule engine, NTPM energy meters can actively support energy saving actions.NTPM meter/ recorders are equipped with a flexible yet simple rule engine for efficient automation of energy management tasks.
With the Rule Engine, NTPM can be programmed to perform automatic actions in the incidence of certain conditions, like overload, voltage drop, frequency change, termperature rise, harmonics threshold crossover, or even some specified date and/or time.
All the operations may be defined to be executed with some time delay using the embedded soft-timers
Rules are defined as simple IF-THEN statements, where measured and calculated parameters are combined to create a set of conditions.
The programmed sequence may be used to close or open an output contact, or to set or reset a soft alarm, which in turn may be used in the next action.
It is possible for example to create a rule that sets an alarm whenever the current energy demand goes above a certain level in the given time period, thus avoiding to cross the preset maximum demand level (and eventual penalties).