Control System Retrofits and Upgradation

Control System Retrofits and Upgradation

Retrofitting refers to the addition of new technology or features to older systems. CoreSystems has the ability to upgrade and retrofit modern technology and equipment to your existing system.

Why is Retrofitting and Upgradation of Control System Necessary?

Retrofitting provides you with the ease of use and reliability of fresh new equipment at little of the expense. Many times, it is very cost effective for the customer to retrofit a machine with new controls rather than buy a new machine. Spare parts are readily available and less expensive than outdated components.

Modern HMI (Human Machine Interface) technology can store machine parameters, saving thousands of dollars in setup and changeover time and can display alarm conditions, making troubleshooting and service easier. Every industrial control panels are completely wired and checked before delivery, thus decreasing start-up time. All retrofit solutions include updated electrical schematics.

Benefits of Retrofitting and Upgrading

• Your upgraded and retrofitted system will have more capabilities than it did before.
• Production will overtake your previous benchmarks.
• The equipment will be more reliable than it ever was.
• You can revive on labor expense as the automation can handle more duties than when the system was first built.
• Save energy
• Reduce downtime due to scheduled maintenance
• Report operating data and productivity information in real-time
• Increase reliability
• Troubleshoot problems quickly with detailed diagnostic information

What is Done During Retrofitting and Upgradation of Control System?

To perform engineering commissioning and work included in an upgrade in a short time, all gears are not upgraded in block; in its place, a phased upgrading is performed. In regards to the phased upgrading, the upgrades of all the equipment are split up and performed in several set inspection periods; consequently, the required capital investment per inspection is reduced. Although doing the upgrade it can suppress the total amount of investment, optimization is achieved according to the ingenuity of the upgrading sequence.

The following three points are evaluated in three separate steps

(1) Level of importance of equipment

The upgrade is planned to start from equipment that is either extremely difficult or impossible to operate the plant in the case that parts in that equipment age and malfunction.

(2) Rebuilt dimensions of gears other than that upgraded

To upgrade existing equipment, temporarily upgrading equipment that is to be upgraded in the next. There are many paths that could be opted for by the end user while deciding on an upgrade. Most of the DCS OEMs have already designed their upgrade paths accordingly. One of the easiest way is to substitute every current DCSs at the same time—along with all human-machine interfaces (HMIs), input/output (I/O) modules, control hardware etc. This path might seem easier to deploy, but it has some factors like longer downtime, reduced efficiency of operational staff as they have to switch to newer systems in one go, and so on inspection period or later is wasteful; therefore, an upgrade sequence that gives rise to a little temporary work as possible is set up.

(3) Completing upgrading work and sufficient testing within the predetermined inspection test period

An upgrading sequence that permits finishing of upgrading work and satisfactory testing in the predetermined inspection test period was exhibited. Because unlike simple upgradation, the phased plan requires proof testing of elements that are newly accepted in widening of the automation scope. There are episodes in which old and new networks survive together. Hence, prevailing pieces of gear and the gateways for conveying their communications should be established as a short-term equipment until the whole upgrading is finished.

How is Retrofitting and Upgradation of Control System Done?

The most commonly used approach is upgrading in steps or phases.

Phase 1: Supervisory layer component upgrade

Supervisory layer components involving HMIs and communication network elements between control systems and HMIs are upgraded in phase 1. This lets the end user to become acquainted with the operations of new system. Having the old HMIs run in parallel with the new HMIs is beneficial because it gives the operators a chance to become familiar with the new system.

Phase 2: Control system upgrade

Phase 2 involves upgrading DCS control hardware. This is a critical phase and has to be planned in more detail as compared to phase 1. It may include downtime depending on upgrade limitations and DCS configuration.

Phase 3: I/O modules upgrade [Optional]

Phase 3 involves upgrading I/O modules and relevant hardware in a DCS. It may also involve downtime based on I/O module configuration and upgrade limitations.

Whatever the reason for replacing a control system, there are 3 major steps that we take to ensure the success of the change out.

Phase 1: Determine how the existing system functions.

Before we can begin retrofitting a controller, we must first fully understand how the existing system works. This requires a certain amount of documentation and knowledge, including:

• drawings such as P&IDs, mechanical, process or electrical
• an understanding of any hardwired safety circuits
• identifying the existing I/O on the controller and the function of each device connected to the I/O
• capturing HMI screens and determining what each active element (such as a pushbutton) does
• a list of all setpoints and alarms that have been programmed into the existing system
• an understanding of all data that may be sent to the SCADA system
• a clear and concise Functional Specification that explains the details of how the system functions and the expected product throughput of the system. If written properly, this document can also be integrated into an Operator’s Manual.
• a Control Narrative that verbally describes the sequence of operation of the machine or system
• list of applicable personnel, environmental and machine safety standards that apply

In most cases, all of this information is not readily accessible. That is not the fault of the owner, as he may never have received that information in the first place.

In any event, if any of the items listed above are not available, we will perform an audit of the existing system so that we have the required information.

This serves a dual purpose. If the owner, does not have that information, he is usually very happy to get it. Also, it gives us the information we need to proceed to the next phase.

Sometimes, this first phase is completed in a couple of days. Other times, it may take a few weeks or even months. We have been involved in projects where there was very little documentation, resulting in us interviewing the machine operators to find out how the system worked.

Phase 2: Create new drawings, write the control program and generate the necessary HMI and SCADA screens

Of course, if we are installing a new controller new drawing will be required.

We will sit down with the owner and go over the new drawings, the new program, the screens, alarms, SCADA data collection and safety concerns. We want to capture any issues that may present a problem in the final phase.

During this phase, our primary goal is to make sure that the system operates as defined in the Functional Specification. However, we certainly understand that the owner might want to make enhancements to increase productivity, decrease downtime or otherwise improve performance. We are more than willing to accommodate any changes to the original operation.

Phase 3: Retrofitting and Start-Up

We work with the owner to determine who will actually remove the old controller and install the new one. Perhaps the owner wants his personnel to perform the work, or maybe he would prefer that the work be done by contractors.

As physical situations vary, sometimes a new controller can be installed in an existing enclosure. Other times, a new enclosure is required. In either case, we will provide drawings and define a step-by-step procedure for installing the new controller.

With the owner, we will determine how much downtime is available to replace the existing controller with a new one. We understand that production demands must be met and we will accommodate those demands. This may require making provisions to operate the equipment manually during the controller changeout. In large systems, it probably would be best to divide the systems into sub-systems, so that the entire system is upgraded a section at a time.

We will define the acceptance criteria for the project. Typically, this is as simple as going through the Functional Specification and confirming that the system operates as stated. However, there may be other variables, and we want to make sure the client’s needs are met.

After we have a clear plan for the start-up, we will monitor and assist in the physical retrofit, load the new program and test the system to the defined acceptance criteria.