Industrial Training

Industrial Training Blog

How to calculate OEE for multiple machines

Overall Equipment Effectiveness (OEE) continues to gain acceptance as an effective method to measure production floor performance. Capturing and recording accurate production floor information is critical for producing reliable OEE Reports.

OEE-Benchmark-Survey

A number of production floors are utilizing manual methods of data collection for producing OEE report. This approach leaves room for both inconsistencies and inaccuracies. With manual data collection, there is usually a second step of manually compiling the data. This is most commonly accomplished by entering in the information into spreadsheets. This manual compilation step also leaves room for both inconsistencies and inaccuracies.

Another disadvantage to manually collecting data for your OEE reports, like with many maintenance and production improvement plans, is sustainability. The more task intensive an improvement plan is, the more likely priorities will change and the OEE initiative will fade away. With an automated data collection system, sustainability is no longer an issue. Once in place the automated OEE reporting stays in place and you need only act on the results.

There are cost effective automated data collection alternatives to manual data collection that significantly improve the accuracy of OEE reports. Automated capturing and recording of “Availability Information” will be covered in this article. Future articles will address the automated data collection of Performance Rate and Quality Rate.

OEE

OEE = Availability X Performance Rate X Quality Rate

Availability – Percent of scheduled production (to measure reliability) or calendar hours 24/7/365 (to measure equipment utilization) or equipment or line status (to measure ability to produce), that equipment or a production line is available for production.

Note: Measures the percent of time that the equipment can be used (usually total hours of 24-7-365), divided by the equipment uptime (actual production).

Performance Rate – Percent of parts produced per time frame, of maximum rate OEM rated production speed at. If OEM specification is not available, use best known production rate or a standard production rate can be established.

Note: Performance efficiency is the percentage of available time that the equipment is producing product at its theoretical speed for individual products. It measures speed losses. (i.e. inefficient batching, machine jams)

Quality Rate – Percent of good sellable parts out of total parts produced per time frame.

Note: Determining the percent of the total output that is good. (i.e. all products including production, engineering, rework and scrap.)

Example: 50% Availability (0.5) X 70% Performance Rate (0.7) X 20% Quality Reject Rate (results in 80%(0.8) acceptable) =30%OEE (Please see DowntimeCentral.com/OEE_TEEP.htm for a free online calculator to practice with.)

Defining What Is Availability

One of the first steps in initiating OEE reporting is defining the parameters for the elements of OEE for the individual piece of equipment, production line or the entire factory. That is clearly defining, documenting and communicating why a piece of a piece of equipment or a production area is unavailable for producing product.

There are three basic approaches to defining availability. The approaches are the percent of scheduled production, calendar hours, and equipment or line status. The schedule production approach defines availability by the production schedule for a piece of equipment, a cell or an entire production line. The calendar hours defines availability as the total time available to produce product which is usually 7-24-365. The equipment or line status approach defines availability in terms that production line or piece of equipment is in a state to produce product. All three approaches are valid approaches. The percent of scheduled production and calendar hours provide a broad view of availability while the line status approach is a much more defined view.

Some examples to consider as causes for unavailability is power to piece of equipment or does the production station have personnel in place. The above two causes may not be enough to define the reason for unavailability. You may need to add data inputs recording if there was materials in place or the status of the infrastructure support (such as air pressure for air driven tools and equipment) as monitoring points to determine if a piece of equipment, a cell or an production line is available to produce a product. Availability must be defined for each area or piece of equipment that will have OEE reports. In some of the instances there will be more than one element that needs to be monitored to determine if that piece of equipment or area is considered available.

Automated Data Collection

Setting a goal of capturing availability status information with no manual data collection or manual compilation for OEE calculations is the first step in improving both the accuracy of OEE reports as wells as reducing the cost to produce the reports. Start with defining what affects availability for various areas of a production facility. Identify the specific data collection points that will affect availability for a given area or unit of equipment. In many cases there are data collection points already in place. For those monitoring points, you need only to retrieve the existing data. In other instances, a data collection monitoring device will need to be installed.

For installing new data collection points, there are available a variety of inexpensive sensors that once installed, can capture the measurement of numerous parameters. These sensors can detect flow rate, weight, quantity, motion activity, phases of electrical power as wells as many other items. The sensors usually come with normally open or normally closed switch contacts. These switch contacts will serve as the data collection points for automated data collection.

Using sensors with switch contact outputs for most monitoring situations are probably the easiest approach for capturing availability data. To monitor equipment starting with power switches and other functions of equipment, it is often the case of adding an extra set of inexpensive contacts to an existing switch on the equipment.

There are other means to capture activity status information including embedded equipment control software and equipment monitoring software that can capture the parameters for availability. What must be factored into the monitoring approach is that each monitoring point must include a time and date stamp.

The data collected from the monitoring points must be transmitted to a database for data retention and reporting. The database that captures and records the status information can be a commonly available P/C database packages such as Microsoft Access®. It is critical that all data points recorded must include time, date and location stamps to support the development of OEE reports. Database report writers can be used to extract the information to produce OEE reports.

In addition to custom in house database systems, there are available integrated data collection systems with application software packages with complete OEE Reports. These systems and reporting can be tailored to each individual facility’s requirements.

The Wireless Connection

The implementation of the wireless LAN or other wireless technologies to capture and transmit availability data greatly enhances the timeliness, utilization and flexibility of the data collection system. Hard wired systems over time, limit the functionality of a data collection system. In the past wireless technologies did not provide the high level of reliability that is required for factories, leaving the hard wired systems as the only alternative. That is no longer true especially with the introduction of the wireless LAN 802.11g standard and advanced 900 MHz technology. Wireless data collection and transmission systems provides for easy reconfigurations of changing production floor layouts or changing production flow activity. A number of off-the-shelf production floor wireless data collection systems are available for use on the production floor.

Cost Justification

The implementation of an automated data collection system with an integrated database provides immediate financial returns. The labor cost associated with manual data collection on production lines by production personnel and the manual compilation of the data to calculate OEE are eliminated with an automated system. The accuracy and integrity of the source data is significant improved. With more accurate OEE reports you will make better financially feasible decisions that will result in even greater savings. The timeliness of the OEE reports themselves are also significantly improved with automated data collections. In most cases, the OEE Reports are available for review the same date as the final element of information is captured.

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April 16, 2018 Posted by | Lean, maintenance, manufacturing | , , , , , | Leave a comment

OAT: Operator Autonomous maintenance Training

Did your company or organization get it’s OATs today?

At least weekly your company’s machine operators should be getting Operator Autonomous maintenance Training (OATs). More specifically, Autonomous Maintenance (AM) Step:0.

AM Step:0 is the preparatory step for the more commonly known 7 steps of Autonomous Maintenance, and Step 0 is crucial to a greater success of your AM program and operator buy-in to that program. AM Step 0 goes a long way to help machine operators understand the need and importance of Autonomous Maintenance Step 1: cleaning.

am-step0

Term: “Autonomous Maintenance Step 0

Definition: “Educating machine operators on the basic knowledge of machine components and functions.”

Autonomous Maintenance (AM) is the process of educating machine operators on the basic knowledge of machine components and functions. AM is the first step of Total Productive Maintenance (TPM) methodology, which is part of LEAN manufacturing program. (Total Quality Management (TQM) didn’t fit well for maintenance, so TPM was developed.)

While some companies have learned and implemented a Step 0 to their AM program, they left out an important ingredient to success. Typically the few who added a Step 0, have the following 4 areas covered in AM Step 0 …

  • PPE: Understanding how important personal protective equipment (PPE) is to the safety of the operators
  • SOE: Identifying the sources of energy (SOE)
  • LOTO: Understanding LOTO (Lock Out/Tag Out) procedures.
  • EO: Basic equipment operation.

What 99% of companies leave out their Autonomous Maintenance Step 0? basic knowledge of machine component functions and maintenance best practices.

It gives the operator a resolve to carry out the handling of preventive maintenance duties with an increased responsibility and authority. (The OATs to do the job better.) Unlike the resigned role they assumed before, AM enables them to take an initiative in handling lighter maintenance procedures among them lubrication, cleaning, bolt tightening, monitoring and inspection. Equipment operators are in constant contact with the machines, therefore have a better understanding of those machines. Machine component and maintenance best practice understanding not only enables them to perform minor maintenance task competently, but also to gives them an idea of how things work and what the maintenance departments adjectives are. With proper machine level autonomous maintenance training and proper supervision, they are inspired and encouraged to better help maintenance and the company reach  their objectives. (Also companies will see an increase in value of the Kiezens being recommended by them.)

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March 18, 2018 Posted by | Education, Lean, maintenance, manufacturing, safety | Leave a comment

How to troubleshoot with a PLC

How to troubleshoot with a PLC is the most common practice.

PLC Technician

Troubleshooting PLC itself is a much less common practice. As PLCs are so reliable. PLC (Programmable Logic Controllers) where designed specifically to be more reliable thank a computer, and more simple so a maintenance technician could work with them, including use them to troubleshoot the machine and automation control process.

The PAC (Process Automation Controller) on the other hand is much more complicated as it is a customized industrial computer, designed with computer IT and programmers in mind, not the maintenance technician or electrician. Likewise, the PAC is a lot less useful for troubleshooting machines and automation control systems. Actually, in that respect, the PAC is the opposite due to its complicity. It is more common end-users (process and manufacturing maintenance personnel)  will be troubleshooting the PAC itself more than using it as troubleshooting tool for the machine. Read on to learn why…

Given that PLC vendor’s intent was to make the PLC easy for the maintenance electrician to use, beyond just using ladder logic as programming language, the added many great software tools to aid the maintenance electrician in troubleshooting machines. You wont find most of these PLC troubleshooting software tools and design features in a PAC. Below are just a few examples. At the end of this article will be a link to read about more. To learn about all of the PLC troubleshooting tools and techniques, and to master PLC troubleshooting, there is currently only one way, attend a hands-on PLC Troubleshooting Training Seminar in St. Louis.

How to troubleshoot with a PLC | Basics

In the real world, 99% of the time, the problem with a machine or process is not the PLC, it is an Input or Output. In other words, it is one of the hundreds of sensors, switches, solenoids, etc. gone bad, out of adjustment or not be made. If the people who wrote the PLC program used PLC programming best practices, the PLC program will be well documented ladder logic. (A symbolic programming language as easy to troubleshoot as looking at a ladder and seeing what rung is broke on the ladder. )

Given the above, based on symptoms reported, you search PLC program for the input or output not working, then trace back through the ladder logic to find out what contact is not being made and that is the sensor or switch causing the problem that you need to look at out in the real world. most of the time that is how you troubleshoot with a PLC, simple as that and takes about 4 minutes to find root cause. (If you have been properly trained by BIN95.)

But … in real life it is not always simple, just most of the time with a PLC. There can be intermittent problems, analog problems, poor management of automation equipment in your facility, etc.

FYI:  Management of PLCs in your facility is also taught in BIN95 PLC Training seminars.

Those little more complex PLC troubleshooting instances that occasionally come up is where PLC troubleshooting software tools that vendors provide, come in. Read How to troubleshoot PLC Allen Bradley to learn more. Below are a few excerpts…

For more cumbersome troubleshooting like intermittent problems, RSLogix 500 has great tools like the Histogram, Custom Data Monitors, trend charts, writing your own diagnostics rungs using Latch bit, etc.

Rslogix 500 Custom Data Monitor    RSLogix 5000 Trend Charts

One example of real world troubleshooting we teach, which is not in books or software, is using RSLogix 500 program “Compare Tool” (Compare Tool may be in your version of RSLogix 5000, or as a separate software for PACs. Or you might not have the tool if you are using PACs, instead of PLCs to control your machinery.) Those not spending years maintaining a PLC/PAC controlled facility may not be aware of the common scenario of one employee on one shift changing the program, and the rest don’t know it. If the troubleshooter suspects that, they can use the program compare and once again within about 15 minutes, find the problem.

PLC Troubleshooting tool

System Data Tables and other data tables found in a PLC (like RSLogix 500) are great troubleshooting tools too, but are not in PACs (like RSLogix 5000). This is another major factor contributing to the use of PACs resulting in increased troubleshooting and downtime. In BIN95’s instructor based PLC training, we also teach best practices in writing PLC programs, so attendees can identify if they are being used before purchasing new machines or systems controlled by PLCs. (Like RSLogix 5000 programmer compensating for missing data table files in their tag naming conventions, for example.) Having a program that was written using PLC programming best practices, with the end user in mind (customer who has to maintain equipment for the next 10-20 years), greatly reduces troubleshooting time. … continued at https://bin95.com/rslogix-5000-troubleshooting.htm

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July 24, 2017 Posted by | Education, Electrical, maintenance, manufacturing, PLC, PLCProfessor, Skill Shortage | Leave a comment

Bug free PLC programming example – 21 CFR Part 11

Source: PLC programming examples under GMP GAMP 5

PLC programming example

GMP (Good Manufacturing Practice), GAMP 5 (Guide for Validation of Automated Systems), 21 CFR Part 11. IEC 25010

Best practices in the PLC programming realm, uses Static Analysis (verification testing). It is probably one of the least covered in PLC training, and therefore least practiced. (With those receiving BIN95 PLC training being an exception to that rule as they have always covered it in the instructor based classes since 1995.) Yet it should be one of the most important parts of the automation control design phases.

See 5 reasons why static analysis of PLC programming is very important.

The most important being Safety, Maintainability and Cost Savings over the life cycle of the equipment that PLC code controls. Many machine designers and system integrator claim they do not have the budget to do static analysis to GAMP 5 level of quality. The cost of not doing so, is passed on to you (the end-user of the equipment) for the life of the equipment.

That cost to end-user, when measured in using TDC (True Downtime Cost)®, can and often is … astronomical over the life of the equipment.

“True Downtime Cost®” is a registered trademark of Business Industrial Network (https://BIN95.com)

March 23, 2017 Posted by | Education, Electrical, engineering, maintenance, manufacturing | , , , , , , , , | Leave a comment

OPC for SCADA and DCS training

What does OPC stand for? OPC = OLE for Process Control

What does OLE stand for? OLE=Object Linking and Embedding

opc-training

OPC communication protocol is the most current to standardize data transfer between all industrial devices. Which make OPC training essential to those working with IIoT.

(IIoT=Industrial Internet of Things)

For OPC SCADA and DCS, this OPC training and software gives you real world experience on free OPC server.

Source: OPC for SCADA and DCS training

February 7, 2017 Posted by | Education, engineering, manufacturing, PLC | , , , , , | Leave a comment

Online MCC Electrical Training

This online motor control center training certificate course for beginners.

Source: Online MCC Electrical Training It is also great for a refresher. Below is a little video tour and demo of the MCC electrical Course…

December 16, 2016 Posted by | Education, Electrical, engineering, maintenance, manufacturing, safety | , , , , , , , , , | Leave a comment

Mechanical Engineering Educational Newsletters

Volume 1, 1st Edition:

A 6 page Mechanical Engineering news letter touching on …

mechanical-engineering-pdf-1e1

  • Protecting bearings from dust.
  • Open trickle chutes for damp bulk product.
  • Changing the service duty of a pump.
  • Flange bolting-up practices.
  • Maintenance costs capital moneys.

Each topic covers basics of mechanical engineering from a real world application perspective by a leading ME in the industry, Download Mechanical Engineering PDF now.

October 20, 2016 Posted by | engineering, maintenance, manufacturing, Mechanical, Skill Shortage | , , | 1 Comment

Siemens PLC Simulator and Plant Simulation Software

This Siemens PLC Simulator and Plant Simulation Software bundle make for a great Siemens training tool.

Source: Siemens PLC Simulator and Plant Simulation Software

Siemens PLC Simulator and Plant Simulation Software bundle, hands-on training tool in a more safe and productive environment. Build your own plant, write your own PLC programs, run the simulation of all.

August 25, 2016 Posted by | Education, Electrical, engineering, maintenance, manufacturing, PLC | , , | Leave a comment

SCADA Basics course using Siemens automation WinCC as tutorial

scada tutorial - simatic,wincc siemens automation.

SCADA Basics Course is also 1/2 the PLC and SCADA Certificate course. The brand used in SCADA tutorial Siemens automation WinCC. Also covers in depth, industrial network security. 4.2 CEUs

Most who view the source page below click on the link to view SCADA Basics Course sample PDF, once they get there.

Source: SCADA Basics course using Siemens automation WinCC as tutorial

Be sure to share with others, they might appreciate it.

June 5, 2016 Posted by | Education, Electrical, engineering, maintenance, manufacturing, PLC | , , | Leave a comment

Industrial Automation Technician Training

With this Industrial Automation Technician Training Bundle of technical certificate courses, you save 32%! The Industrial Automation Specialist Training bundle includes the 7 following certificate course software topics. PLC training, PAC, HMI, VFD, motor controls trainer, troubleshooting trainer and the DeviceNet tutor.

Source: Industrial Automation Technician Training

Automation Technician Training

7 Certificate courses (CD or Download format available)

February 18, 2016 Posted by | Education, Electrical, engineering, maintenance, manufacturing, PLC, safety, Skill Shortage | , , , | Leave a comment

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