Revere Electric

Safety Lifecycle: Stage 5 Maintain & Improve

2019-08-27T18:26:19+00:00

The Functional Safety Lifecycle and YOU!

Stage 5: Maintaining and Improving Your Safety System

By Tyler Knutson, Automation Specialist, Safety

In Stages 1 -4: You learned the importance of having a proven method of providing documentation showing a machine is safe to operate, mitigation techniques required, developing the functional safety requirements for your newly assessed machine, using the tools needed to properly design & verify your safety system, and ensuring your safety system was installed properly and to your specifications.

For Stage 5, we will focus on ensuring that your system is periodically tested for compliance and re-evaluated if changes are made to your machine.

How do I Maintain my Safety System?

Periodic testing* should be done to verify proper system functionality
Machine modifications that affect safety require validation of the safety function may require additional assessments:
- Program changes
- Safety system use
- Hardware or software changes
- Machinery changes
- System modifications
- Speed changes

*Periodic Testing Requirements: The standards say that periodic testing should be done to verify proper system functionality. (There is no defined period or timeline that is suggested)

"Should the safety-related software be subsequently modified, it shall be revalidated on an appropriate scale." (ISO 13849-2, 9.5)

Providing safety for your facility doesn’t just stop at the hardware installation and verification. It′s important to make sure that your facility is kept up to code and your employees are following the guidelines laid out in the designated process. Changing the system without following the safety lifecycle could result in additional damages to your organization, should someone get hurt.

In the end, your organization should have a copy of the following pieces of documentation:

- The relevant standards which you’ve designed to (per Stage 1: Risk Assessment)

- The functional Safety Requirements & Functional Safety Description of the SRP/CS (per Stage 2)

- Fault Exclusions & Assumptions

- Bill of Material (Stage 3)

- Typical Wiring Diagram (Stage 3)

- SISTEMA Performance Verification (Stage 3)

- The Verification and Validation Plan (Stage 4)

For more information into providing the appropriate products to meet your risk assessment and functional safety specifications, please review the following:

Rockwell Automation Machinery Safebook 5

Rockwell Automation Pre-Engineered Safety Functions

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Integrated Safety

2019-03-20T18:20:21+00:00

Rockwell Automation Integrated Safety with Motion Control

Over the past decade safety has become a high priority on the plant floor, and this is great to hear. Why? It means that employers want you to go home at night healthy and safe. These days it seems like you can't move without tripping a safety circuit on a machine and this has been changing the way we think about safety. With the advent of safety over Ethernet, we can monitor the safety system, make decisions, and notify people of problems faster than ever before. There is even an effort to include Collaborative Safety (where a person and a machine meet) as a focus moving forward to increase up-time.

When it comes to safety and Motion Control products, Rockwell’s Safety Servo Drive products are designed to help minimize downtime and reduce energy and production waste, while helping improve machine operating efficiencies. The Kinetix® 300, 350, 5500 and 5700 all feature built-in safety functionality. With Safe Torque-Off, a drive output is disabled to remove motor torque without removing power from the entire machine. The Kinetix® 5500 and 5700 also allow for the configuration of safety over Ethernet when a safety controller is present. This helps reduce panel wiring and increases the diagnostics into your safety application.

The Kinetix® 5700 advanced safety tools use integrated drive safety functions, or instructions, to help your system meet specific performance criteria. When integrated into control and motion systems, pre-certified safety functions can help companies save on project costs and improve overall system reliability. The list below shows some of the advanced safety features on the Kinetix® 5700.

Safe Stop 1 (SS1) - Initiates and monitors the motor deceleration rate within set limits to stop the motor and initiates the STO function when the motor speed is below a specified limit.
Safe Stop 2 (SS2) - Initiates and monitors the motor deceleration rate within set limits to stop the motor and initiates the Safe Operating Stop function when the motor speed is below a specified limit.
Safe Operating Speed (SOS) - Prevents the motor from deviating more than a defined amount from the stopped position. The drive provides energy to the motor to enable it to resist external forces.
Safely Limited Speed (SLS) - Prevents the motor from exceeding the specified speed limit.
Safely Limited Position (SLP) - Prevents the motor shaft from exceeding the specified position limit(s).
Safe Direction (SDI) - Prevents the motor shaft from moving in the unintended direction.
Safe Brake Control (SBC) - Provides a safe output signals to control an external brake. The SBC function is coordinated with the STO function.

Please keep in mind that a Safety Risk Assessment of the machine should be performed on any machine where people interact.

The most complicated part of safety is understanding all the rules and regulations that may apply to you and your machine. Luckily there are publication that summarize these standards (Rockwell Automations Machinery SafeBook 5) and services to help you along with this process. Just ask your Revere Electric Account manager or our Safety Specialists for more information on any safety related products or services.

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Stage Three: Proper Design & Verification Techniques

2018-10-17T16:14:58+00:00

The Functional Safety Lifecycle and YOU!

Stage 3: Proper Design and Verification Techniques

Machine safety has become more recognized than ever before. Employers and equipment manufacturers are tasked with providing equipment that is free from recognized hazards yet remain efficient, productive, & competitively priced. Revere Electric Supply, in partnership with Rockwell Automation, can provide you the tools needed to improve compliance, simplify development, reduce design time, and reduce costs.

In Stages 1 & 2, you learned the importance of having a proven method of providing documentation showing a machine is safe to operate, mitigation techniques required, and developing the functional safety requirements for your newly assessed machine. For Stage 3, we will focus on providing the tools needed to properly design and verify your safety system.

During the Design & Verification process, the user will use the functional specifications to help select components that meet the criteria & performance level laid out during the risk assessment.

What Considerations Should go into Developing Functional Specifications?

What mitigation technique should I use?
What circuit structure should I use? (Cat 1, Cat 2, Cat 3, Cat 4)
What safety products should I use?
Where are all my safety products located?
What kind of diagnostics do I need?

In at the end of reviewing the considerations, you have established the products and guidelines needed to design your system. The products should meet your required performance level, be wired to the circuit structure designed, and meet the safety function designed in Stage 2.

Applying the Appropriate Design

Make sure the products being used meet the criteria laid out in the risk assessment and functional specifications.
Do the products selected include all the necessary safety and reliability data?

For a complete list of Input, Logic, & Output Devices, please visit: https://ab.rockwellautomation.com/Safety. Note that Revere Electric is here to help you move forward with product selection to meet the requirements set by your risk assessment.

Verifying the Design

The most common method to verify your design is known from a 3^rdParty Software Program called SISTEMA Performance Level Calculator.With SISTEMA, you can input your devices and verify that the application will meet your required design.The report generated by SISTEMA can also be provided to your customer to help as well. Note that our safety partners can help you move forward with the validation process to meet the requirements set by your risk assessment and design process.

Rockwell Automation has assembled numerous Machinery Safety Functions that are applicable to current Input, Logic, & Output devices. Along with those devices, you can example of product selection that highlight the expectations of the safety system in a common environment. If you are working on current project, please use these as reference to help you move from your Risk Assessment (Stage 1) to Design and Verification (Stage 3).

For more information into providing the appropriate products to meet your risk assessment and functional safety specifications, please review the following:

Rockwell Automation Machinery Safebook 5

Rockwell Automation Pre-Engineered Safety Functions

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What is an Absence of Voltage Tester?

2018-08-24T15:01:10+00:00

AVT : Absence-of-voltage Testers

Absence-of-voltage testers (AVTs) are permanently-mounted testers used to determine if a circuit part is de-energized before opening doors or covers to access electrical equipment.

UL 1436

Absence-of-voltage testers are a new product listing category that was recently added to UL 1436, Standard for Outlet Circuit Testers and Similar Indicating Devices. absence-of-voltage testers are designed to run internal diagnostics to perform the live-dead-live type of verification with a secondary test source and actively indicate the absence of voltage for fixed installations.

The benefit of absence-of-voltage testers will be significant to the qualified worker performing these tasks. Today, the sequence of activities includes turning off power, performing Lockout / Tagout procedures, selecting proper PPE for the hazard - assuming the presence of power and testing with a hand-held test device. Now, with the permanently mounted absence-of-voltage tester, the worker will have the ability to (automatically) conduct the steps without being exposed to a hazard and needing PPE. The worker can now verify absence of voltage while eliminating multiple steps in the standard sequence.

Would you like to learn more about absence-of-voltage testers or see a demo? Contact your account manager or fill out our solutions information request form.

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Impacts of NFPA 70E 2018 on Arc Flash Studies

2018-05-14T16:11:31+00:00

Are you ready to comply with the National Fire Protection Association’s (NFPA) 2018 edition of NFPA Standard 70E for electrical safety in the workplace? This standard provides requirements to help employers reduce risks to employees from arc flash and other hazards when working on or near energized equipment.

The 2018 edition of NFPA 70E makes several important changes related to arc flash safety. Significantly, it promotes the importance of the hierarchy of risk control methods (including placing the hierarchy on the front cover of the 2018 edition). It also considers the likelihood of occurrence of arc flash hazards when assessing risks.

In NFPA 70E 2018, the hierarchy of risk control methods has been moved from an informational note into the main text of the standard, which emphasizes its importance. In this hierarchy, elimination of the hazard is the first priority, and each subsequent method is considered less effective than the one above it.

Notably, personal protective equipment (PPE) is listed as the last priority in the hierarchy. Thus, arc flash safety should not be solely a matter of determining the right level of PPE for a given task. For each process, PPE only comes into use after other more effective means of risk control have been considered.

As you consider your next arc flash analysis, ask yourself:

Has your electrical equipment been properly maintained and tested according to the manufacturer recommendations?
Have you reviewed the areas in your facilities to determine how you can eliminate or reduce the arc flash hazards, even if you have appropriate PPE?

To learn more about the impacts of NFPA 70E 2018 or to discuss arc flash studies, contact us.

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Stage 2: Determine the Functional Safety System Requirements

2018-04-25T14:24:49+00:00

The Functional Safety Lifecycle and YOU!

Stage 2: Determine the Functional Safety System Requirements

In Stage 1: Understanding Hazard & Risk Assessments, you learned the importance of having a proven method of providing documentation showing a machine is safe to operate, or mitigation techniques are required. For Stage 2, we will focus on developing the functional safety requirements for your newly assessed machine.

A functional specification uses the data collected from the Risk Assessment to determine the appropriate mitigation techniques used in protecting the personnel in and around the machine.

What Considerations Should go into Developing Functional Specifications?

What are the different modes of operation?
What are the tasks and hazards associated with each mode of operation?
What can we do to protect employees from these hazards without impacting their ability to do their job?
What is the overall system structure?
How will the system operate in each mode of operation?

At the end of reviewing the considerations, a Safety Function is developed. This can be one simple function or it can extend to numerous devices, depending on the number of tasks / hazards found during the risk assessment.

A Safety Function Consists of Three Components, They are as Follows:

Input Device – Considered to be the “Start” of the safety function. The Input device will send the signal to the logic device that its safe state has been altered, thus an action triggered by the logic device should take place (Light Curtains, Safety Mats, Guard Door Switches, Trapped Key, Non-Contact Switches).
Logic Device – Considered the “brains” of the safety function. The logic device will read the status of the input device and output device and determine if the system needs to be put into a safe state. The number of input devices will generally dictate which logic device is appropriate (MSR & GSR Safety Relay, CR30 Configurable Safety Relay, Compact GuardLogix, Control GuardLogix).
Output Device – These are the “action items” of the safety function. They are the devices that can remove power from the actuator, or prevent rotational energy from being delivered to achieve a safety stop (Safety Control Relays or Contactors, drives and Servos).
Functional Safety Description – A detailed description of how the input, logic, and output devices are designed to work for the specified Safety Function.

For a complete list of Input, Logic, & Output Devices, please visit: https://ab.rockwellautomation.com/Safety.

At the end of the day, Rockwell Automation has assembled numerous Machinery Safety Functions that are applicable to current Input, Logic, & Output devices. Along with those devices, you can see samples of the functional safety descriptions that highlight the expectations of the safety system in a common environment. If you are working on current project, please use these as reference to help you move from your Risk Assessment (Stage 1) to Design and Verification (Stage 3).

Rockwell Automation Machinery Safebook 5

Rockwell Automation Pre-Engineered Safety Functions

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The Functional Safety Lifecycle and You!

2018-04-24T19:29:13+00:00

Stage 1: Understanding Hazards and Risk Assessments

A hazard analysis / identification looks at an entry point and provides protection to guard against a general hazard (pinch point, hand crush, cutting tool, etc.).
A task-based risk assessment will see the hazard, but look at multiple ways that it is being used. For example, an operator who uses the machine daily will work with the machine differently than a maintenance person, cleaning crew personnel, supervisors, or even visitors.

Why Do a Risk Assessment?

A Risk Assessment is a proven method of providing documentation that a machine is safe to operate.
NFPA 79: – an Occupational Safety and Health Administration (OSHA) national consensus standard – states that the safety circuit design shall be based on a Risk Assessment.
ANSI RIA R15.06: standard requires the manufacturer to have a documented risk assessment.
ANSI B11.0 4.11: Where modifications are made to the machine/system (for example, intended use, tasks, hardware, and software), a risk assessment / risk reduction process shallbe repeated for those parts of the machine/system being modified or affected.
As existing standards are updated and new standards emerge, there will continue to be more emphasis placed on conducting Risk Assessments.

End User Benefits

Provides proof of due diligence
Consistent risk reduction across multiple plants
Identifies risk reduction techniques for new & upgraded equipment
Produces a more complete machine safeguarding solution

OEM Benefits

Meets end-user equipment purchase requirement
Provides OEMs with evidence of due diligence, potentially reducing litigation after the equipment ships
Helps define safety solutions that improve productivity
Provides competitive differentiation

To avoid workplace injury, OSHA requires adequate guarding or complete energy isolation from the hazard. However, for machine maintenance, this is found to be impractical as production time can be lost and may still cause injury (pneumatics, hydraulics, etc.). Therefore, OSHA developed the Minor Servicing Exception for these circumstances.

If minor servicing activities are routine, repetitive, and integral to the operation of the system, a facility or machine builder may use “alternative measures” to guard the machine from hazards. Cleaning jams, tool changes, loading parts, etc. may fall under the Minor Servicing Exception.

Risk Assessments are the first step in determining which process should be used for safe machine operation. For a task around a specific hazard, the Risk Assessment will determine if the machine should be locked out & tagged out, hard guarded, or if acceptable alternative measures can be taken.

Risk Assessment is a process designed to:

1.        Identify hazards associated with human interaction to processes or machines

2.        Estimate the risk level associated with the hazards

3.        Evaluate the risk level to determine if the risk level is acceptable

4.       If the Risk is too high, apply a Risk Reduction Technique

For more information into the standards and guidelines around a risk assessment, as well as details into Rockwell Automation Safety Assessments, please review the following:

Rockwell Automation Machinery Safebook 5

Rockwell Automation Safety Assessments

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How Can You Improve Productivity "On the Line?"

2018-02-22T22:45:26+00:00

How Can You Improve Productivity "On the Line"

In manufacturing, if you see a conveyor, there is a high probability that you will also see cable pull switches.

Cable pulls perform an important function in the emergency stopping of a line. A line may need to be stopped for any number of reasons; some of those reasons include, but are not limited to:

Personal Safety
Machine Safety
Product Damage
Package Controls

While cable pulls are often mandatory, they can potentially cause problems that could have a negative impact on productivity. Some of those problems include:

Increased Installation Time
Nuisance Trips
Tension Adjustments
Longer Cable Runs
Locating Trip Locations

Wouldn't it be nice to have a more efficient cable pull switch?

Well, now we do! Rockwell Automation's Guardmaster LifeLine 5 eliminates all the problems mentioned above with one switch!

Rockwell Automation's LifeLine5 Gives you:

Solid state operation - first in the industry
Enhanced safety and productivity with microprocessor-based
Performance at the highest safety ratings, even in series connection
TÜV Approved
PLe Cat 4 according to EN ISO 13849-1
SIL CL3 per IEC 62061 and IEC 61508
EN ISO 13850 and IEC 60947-5-5
100 m (328 ft) maximum cable span
Electronic rope monitoring system - monitors the cable span
Compensation for thermal expansion
Built in margin indication to help reduce downtime
Wide operating temperature range (-20°C to 75°C (-4° F to 167° F)
270-degree visible LED indicators which offer diagnostics for switch and tensioning setup
Rugged stainless steel (IP69K) or die cast aluminum (IP66) housing with an optional e-stop
Available with a 5 -or 8-pin Micro M12 connector
OSSD outputs (2 OSSDs for safety, 1 Auxiliary, 1 Tension/margin (8- pin model only)

Don’t take it from us, check out the video below to see the benefits of the Lifeline ™ 5 or better yet, contact Revere’s Industrial Controls Product Manager for a Hands-On demo!

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Arc Flash Update

2017-10-06T15:26:19+00:00

NFPA70 (National Electric Code) 2017 has a key revision in regards to Arc Flash compliance:

To continue raising awareness of incident energy hazards, service entrance equipment rated 1200 A or more must now be clearly labeled for fuse and circuit breaker selections. Reduction requirements continue to reduce incident energy at service entrance panels.

Updates include:

110.16(B) – Service entrance equipment rated 1200 A and higher must now include a label that shows the nominal system voltage, available short-circuit current, clearing time of the service overcurrent protective device based on that available short-circuit current, and the date the label was applied. The exception permits a 70E-type label to take the place of this information.
240.67 – For fuses rated 1200 A and above, this new requirement which doesn't go into effect until January 1, 2020, and mirrors the requirements of 240.67 mandating arc energy reduction methods to be employed when the arcing current clearing time is greater than 0.07 seconds.
240.87 – Use of a device's instantaneous trip unit was added as one of the methods to reduce arc energy when the arcing current is in the instantaneous region of the circuit breaker by design. This does not mean we can field modify the settings of the breaker to meet this language.

Do you need assistance getting into compliance? Let Revere Safety team get you on track. Contact a domain expert today.

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Grace Engineered Products -We've Got You Covered

2016-06-23T00:00:00+00:00

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Keep people safe and assets secure with Grace's NEW fully customizable HMI cover kit, the GracePort®+

The GracePort®+ is a UL Recognized large protected housing that secures Human Machine Interfaces (HMIs) and other valuable electrical components. The cover kit has the added benefit of including our custom line of GracePort® components to be installed within the housing.

A robust polycarbonate cover and corrosion resistant 316 stainless steel hinge pins help protect from environmental contaminants such as UV, dirt, dust, oil and water, making the GracePort®+ well suited for outdoor applications. The padlockable housing adds an additional layer of protection by only allowing authorized personnel access to the components within the cover kit.

Customization of the GracePort®+ provides the ability to select specific configurations to meet precise needs with Grace's line of PESDs and GracePort® components. Customers will also be able to request special text and company logos to be printed on the faceplate. The faceplates can be customized to provide housing for many leading manufacturers' HMIs.

Interested in learning more, contact your Revere Account Manager or email us at safety@revereelectric.com.

GracePort.pdf

5 components your Lockout / Tagout program can’t live without

2016-04-11T00:00:00+00:00

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When considering compliance with the lock out‐tag out regulation, many will assume locking out the hazardous energy sources is all it takes. In reality, there is much more than just creating a safe work environment during servicing.

While that is the overall goal, there are 5 components of a proper energy control program that will help ensure the safety of your employees.

Corporate Policy

A corporate policy is meant to define the scope and rules of the lockout‐tagout program. It explains when lockout is necessary, who is authorized to perform work, how to safely lockout equipment, and how to address special circumstances. Every aspect of the program and what everyone’s responsibility is when it comes to lockout / tagout should be outlined in the company’s policy.

Employee Training

In order to ensure work is safely performed, employees who will be involved in servicing must be trained to understand and recognize the dangers associated with lockout‐tagout. They must know how to properly isolated energy sources and apply the correct lockout devices. Proper shutdown and restore techniques should be taught as well as how & when to use lockout‐tagout procedures.

The training should also cover special circumstances such as group lockout so employees understand the corporate policy. Affected employees (those not performing lockout / tagout) will also need awareness training on the purpose and use of lockout‐tagout.

Documented Lockout-Tagout Procedures

Machine specific lockout‐tagout procedures should be developed for each machine at the facility. These procedures need to list the energy sources to be isolated during the lockout, residual energy sources that must be released, and any additional warnings or hazards. Disconnect types, locations, and magnitudes need to be a part of the procedures. Steps to shut down and lockout the equipment should be included as well as steps to restore the system to normal operations. Finally, methods to verify the equipment is in a neutral state are necessary to protect worker safety during lockout.

Proper Hardware and Devices

In order to lockout the equipment, specific locks, tags, and devices are needed. They must withstand the environment and not be easily removed without excessive force.

All energy sources that accept a padlock must use one; valves and disconnects that don’t accept a padlock will need specific hardware such as a cable or breaker lockout devices to keep the disconnect in the off position. These devices will need to be properly applied and locked out.

Locks and devices must identify the individual performing work, along with additional information about the purpose and duration of the lockout. If needed, a durable informational tag can also be applied to the isolation point, identifying the authorized employee(s).

Annual Inspection

At least once per year, the energy control program must be inspected to identify any errors that may exist. Procedures need to be reviewed to verify they accurately reflect the equipment and needs of the workers.

Authorized employees also must be observed performing lockout‐tagout to ensure they follow the procedure and create a safe work environment when performing maintenance. .

Summary

All companies need these five components in order to run a successful lockout / tagout program. It will clarify the expectations and make maintenance activities run smoother. Most importantly, following these steps will guarantee a safe work environment for both the authorized employees and those affected by lockout / tagout.

How can we help you make sure you are following the fiev somponents to a successful lockout-tagout program?

ESC Lockout-Tagout Services - A Rockwell Automation Company

ESC Lockout Tagout Checklist

OSHA's $afety Pays Program

2014-10-17T00:00:00+00:00

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OSHA's "$afety Pays" program can help employers assess the impact of occupational injuries and illnesses on their profitability. This program uses a company's profit margin, the average costs of an injury or illness, and an indirect cost multiplier to project the amount of sales a company would need to cover those costs. The program is intended as a tool to raise awareness of how occupational injuries and illnesses can impact a company's profitability, not to provide a detailed analysis of a particular company's occupational injury and illness costs.

The"$afety Pays" programwill:

Allow users to pick an injury type from a drop-down list or to enter their workers' compensation costs
Prompt users for information to do the analysis, including their profit margin and number of injuries
Generate a report of the costs and the sales needed to cover those costs

Start the Safety Pays Program

For additional information on how "$afety Pays" works, see Background of the Cost Estimates

Note: The Cost Estimator requires JavaScript to be enabled in your internet browser. An alternate text version is also available.

If you have safety or health problems in your workplace, please contact your local OSHA Area Office or the OSHA On-site OSHA On-site Consultation Program in your state.

Legal Considerations for Machine Safety

2014-04-28T00:00:00+00:00

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Is your plant safe? Hopefully this is a question that is being contemplated and addressed on a continual basis. The Occupational Safety and Health Administration governs the area of machine safety and it has been proven that “Compliance with OSHA standards can not only help prevent needless workplace tragedies from accidents, but it can also help minimize the number of injury-related employee absences, keep workers' compensation and other insurance costs to a minimum, and promote higher productivity from employees who can feel secure that the company is looking out for their safety.”

Those companies not in compliance with OSHA can suffer large fines simply for non-compliance, but if there is a work related injury or death that occurs due to a known non-compliance, the litigation costs can be devastating to an organization. Did you know that approximately one-half of all amputations occur in the manufacturing sector? Amputation is one of the most severe and crippling types of injuries in the occupational workplace, often resulting in permanent disability. A review of Bureau of Labor Statistics (BLS) annual survey data, National Institutes of Occupational Safety and Health (NIOSH) data, and OSHA Integrated Management Information System (IMIS) data indicates that amputation injuries are widespread throughout many industries and involve a wide range of activities and equipment, but again, one-half of all amputations occur in the manufacturing sector.

Knowing that machine safety is a very important topic, we are honored to have a renowned lawyer, Donald H. Carlson, present at our Solutions Symposium at the Tommy Thompson Center on Wednesday, May 14. Mr. Carlson will be speaking on the importance of safety compliance and will explain how companies like yours can reduce the risks of litigation.

Don has lectured extensively on issues such as products liability, toxic torts, trial practice, insurance coverage and commercial litigation for the Wisconsin Bar Association, the Milwaukee Bar Association, the Wisconsin Association of Corporate Counsel, the Marquette University Law School, and the Professional Education Seminar Group. Additionally, he regularly participates in the Institute of Trial Practice sponsored by the American Board of Trial Advocates and the State Bar of Wisconsin.

*statistics taken fromwww.osha.gov.