Introduction to the SLC-500 Histogram We use the SLC-500 Histogram to track infrequent bits (such as Intermittent problems) and bits that change quickly in the processor. A common use for the histogram is to find intermittent problems. In this post, I will guide you through the procedure for setting up Read More »
Introduction to SLC to ControlLogix Messaging SLC to ControlLogix Messaging might be easier than you think. For example, the SLC 5/05 will take 5 integers from the N10 data file, and send those 10 integers to the Allen Bradley ControlLogix processor. The ControlLogix does not have the same addressing structure Read More »
Introduction to Scale With Parameters (SCP) We use the Scale With Parameters (SCP) instruction to convert raw data into Engineering Units. Examples of engineering units are Percent, RPM, Pounds of pressure, gallons per minute, etc. The data we get from an analog input module, such as the 1746-NI8, is called Read More »
Introduction to the SLC 500 Retentive Timer The SLC 500 Retentive timer (RTO) keeps total track of time. Initially, when the rung goes true, the accumulated value begins to increase. When the rung goes false, the accumulated value stops increasing. The next time the timer goes true, the accumulated value Read More »
Introduction to the SLC 500 Off Delay Timer The SLC 500 Off Delay Timer (TOF) Delays the DN (Done) bit from shutting off. Many people will find this as the most confusing type of timer. Once you understand it’s operation, and relate it to a real process, however, its easy Read More »
Introduction to the SLC 500 On Delay Timer The SLC 500 On Delay Timer (TON instruction) can delay an event from taking place. When the run of logic goes true, the EN (Enable) bit goes true. The timer will then start timing (the TT bit goes true). After the accumulated Read More »
Introduction to SLC 500 Data Tables SLC 500 Data Tables store values. You can think of data tables as “Data Registers” or “Variables”. In a default project, 9 standard data tables are created automatically. Each of these data tables can generally store up to 255 elements. We will discuss the Read More »
Introduction to the SLC 500 Processor The SLC 500 Processor is the main component of your SLC 500 system. The processor contains data files (which store data) and program files (which manipulate data). There are five modular processors in the SLC 500 Family (5/01 to 5/05). In this post, we Read More »
Introduction to the SLC 500 Power Supply The SLC 500 Power supply supplies power to the local chassis. The power supply typically does not power inputs or outputs. This is a switching power supply, so it will provide quite a bit of current for the size compared to the Read More »
Introduction to the SLC-500 Digitial Output Module The SLC-500 Digital output module turns digital field devices on or off. Examples of these field devices include lights, solenoids, and relay coils. Think of outputs as “Control” In this example, we have a 1746-OB16 module. This module acts as 16 switches. When Read More »
