Predictive Load Management (PLM) is able to eliminate full cycle firing drawbacks.

Two key strategies are included in the PLM function: Load Balancing (or Load Sharing) and Load Shedding. Overall the load balancing strategy is the most important part of PLM to combine multiple SCR’s that are full cycle firing together with a stable overall power demand.

Load balancing is a strategy of equally distributing power of different loads to obtain an overall power consumption as stable and balanced as possible thus eliminating peaks of power. Each heating zone controlled by an SCR controller, is defined by an output power, cycle time and a maximum power (max capacity), which can be pictured as a rectangle. Rather than letting these rectangles pile up randomly, the PLM equipped controller uniformly distributes them thereby ensuring that at any given moment the overall power is as stable and balanced as possible. It is important to understand that the PLM function does not change the output power but rather balances and shifts the power evenly thereby eliminating any disturbance. The result is optimum load management through intelligent load balancing and load sharing, a strategy that will eliminate peaks and flicker and even the out overall power usage.

By using the PLM function, manufacturers are now able to use zero cross firing for their system without any drawbacks. Eliminating Phase Angle firing significantly improves the power factor which in turn results in substantial savings.

Additionally, using energy more efficiently (i.e. substantially decreasing the reactive power (KVAR) results in less power generated by the utility company. In fact, we should consider that consuming reactive power is in the end simply a waste of energy. While a bad power factor forces the utility company to generate this extra reactive power, it will be of absolutely no use to the end user. Besides saving costs, implementing a best practice of efficient energy consumption also results in considerably less CO2 emissions released in the atmosphere.

This is an excerpt from an article by René Meuleman

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