Programmable Logic Controllers (PLCs) and How They Have Revolutionised Sewage Pumping

Sewage management authorities have to deal with a high amount of waste these days. The growing populations in urban and suburban areas continuously call for effective sewage management policies and techniques. Electronically controlled pump stations illustrate the progress that has been made over the years to ensure effective management of wastewater. These systems rely on devices called Programmable Logic Controllers (PLCs) to monitor sewage pumping stations. They help you identify faulty pumps, overflows and pipe faults among other things. Here is a comprehensive look at PLCs to help you gain more insight:

Overview of a Programmable Logic Controller (PLC)

A Programmable Logic Controller refers to a rugged, industry-based computer that has been fine-tuned to keep an eye on manufacturing procedures. Good examples of such processes include car assembly lines, food and beverage canning among others. Sewage pumping stations can use a similar control system because they are connected to a large network of domestic sewer lines, making it hard to monitor each one of them manually. Notably, these computers are made to withstand the tough conditions they are exposed to along sewage lines. They are able to stand long periods of immersion in chemically polluted water, corrosion, abrasion and high pressure in the sewage systems. 

Use of Loops and Scan Times 

PLCs rely on numerous sensors to monitor sewage pump stations. The sensors work with scan time, which is a number of loops executed repeatedly any time the system is running. When a loop starts, all the inputs of the technicians are copied to an image table or memory. The PLC then runs all the commands issued from the first all through to the last loop, depending on the number of the commands issued. In some cases, the loops are also referred to as rungs.  Scan times occur when the processors of the LPCs take some time to process all the output and input information. Powerful processors may require a few milliseconds to do it while the less powerful may need a few seconds. 

Interface with Human Resources

Even though PLCs are self-sufficient and reliable, there is still need for a human interface. You need people to configure the devices, report and respond to alarms and control the systems every day. PLCs are diagnostic devices, but the solution to your pump stations will come from the team that you assign to respond to the output from the PLCs. For instance, the devices may detect an overflow, but they may not be able to stop it in places where there no valves in the system.