Tag Archives: CSV data logger

Productivity 1000 Series PLC PID Ramp Soak Instruction

PID Ramp Soak Instruction
The purpose of a ramp soak instruction is to make gradual, controlled changes in temperature (Ramp), followed by a temperature hold (Soak) period.
We will be using our Proportional-Integral-Derivative PID Instruction that we looked at last time to apply the ramp/soak instruction.

Using the immersion heater in a cup of water to keep the temperature at a constant value, we will be adjusting the profile of the temperature as we increase the set point (Ramp) and hold that set point for a predetermined time. (Soak)

We will be modifying our existing program from our PID loop instruction. Let’s get started. Continue Reading!

Productivity 1000 Series PLC PID Instruction

PID Loop (PID) Instruction (Auto Tuning)
A Proportional-Integral-Derivative algorithm is a generic Control Loop feedback formula widely used in industrial control systems. A PID algorithm attempts to correct the Error between a measured process variable and the desired setpoint by calculating and then outputting a corrective action that can adjust the process accordingly and rapidly, to keep the Error to a minimum.

The following links will explain the PID instruction.
https://www.csimn.com/CSI_pages/PIDforDummies.html
http://www.ni.com/white-paper/3782/en/
https://en.wikipedia.org/wiki/PID_controller
We will be using an immersion heater in a cup of water to keep the temperature at a constant value. Using the Productivity Suite software we will perform an autotune on our PID instruction.

Our immersion heater will be controlled through a relay using time proportional control from our PID output. Let’s get started. Continue Reading!

Productivity 1000 Series PLC Modbus TCP Ethernet Communication

The productivity series of PLCs comes with 4 built-in communication ports for easy connectivity to your PC or various industrial networks. Ethernet protocols like Modbus TCP can be utilized with the RJ45 port on this PLC. Modbus TCP is an open (published) protocol that uses the Server (Master) / Client (Slave) architecture. It’s a very common protocol used in industrial automation controls.

We will be using the RJ45 (Ethernet) port to communicate to a Click PLC. Modbus TCP will be the protocol used on this Ethernet communication media. The Productivity 1000 PLC will be the server and the Click PLC will be the client. We will be creating a network between the two PLC units. A heartbeat will be used so if communications is lost, the server (slave) will know. The throughput time will be timed by using a small program in the Click PLC. You will soon see how the Productivity Series of PLC’s is the best way to handle communication to other devices. Let’s get started. Continue Reading!

Productivity 1000 Series PLC Data Logger

The productivity series of PLCs has a built in data logger. This easy data logger will log up to 64 tag values on a USB (Micro SD) storage device connected to the CPU. The logs will be stored in CSV (Comma Separated Values) file format. Logging can be triggered by the rising edge transition of a Boolean tag (event) or configured to occur at regular intervals (scheduled).

A USB storage device should be normally connected if logging data. The CPU maintains an internal 73KB buffer for temporarily logging data while no USB storage device is present. Data in the buffer will not be retained through a power cycle. Let’s get started. Continue Reading!