To complete the fuel oil installation a control system is used to make all the various pieces of equipment work together. Control systems can take the form of just simple motor starters with “Hand-Off-Auto” switches to complex systems making use of several control panels each with PLC’s and Touch Screen Operator Interfaces. These control panels will communicate with each other making use of data links with the addition of some hardwired interlock signals. In some systems a “Master Panel” is employed to monitor the whole system and provide a point of contact to a Building Automation System (BAS).
Control systems in the basic form come with either relay logic or PLC logic. For those applications where the control requirements are very simple a relay logic system is used. But the vast majority of the systems make use of a PLC which is pre-programmed at the factory. These PLC systems allow for great flexibility and expandability. They also allow for communication between this PLC and other devices. They provide LED indication of the status of inputs and outputs to make diagnosing of problems easier. With a computer and the necessary software it is easy to make changes to the program in the field.