As more innovations in existing industries happen, so do these necessitate capable power systems that are capable of protecting the power network and other equipment. For this reason, industrial businesses should plan regular protection relay upgrades.
A good power system works with virtually no interruption to all the loads attached to it. This is the prime reason why most power producers and utilities are considering an upgrade from old electromechanical systems to new-generation solutions available in the market today.
In general, power runs through a high-voltage transmission line. These lines are placed outside and exposed to damaging elements like the weather and accidents. Sometimes, bare power lines can meet insulator damage or falling objects, resulting in both electrical and mechanical fault.
To allay these problems, old relays such as electromechanical, numeric relays, and old solid-state relays need to be considered for a modern relay upgrade. This is to isolate the cause of the problem so that it does not affect the whole system and shut down equipment interconnected to it.
Benefits of Protection Relay Upgrades
Upgraded protection relay systems mean less direct and interconnecting wires, which consequently improves the reliability of the system. Multifunction logic and dynamic settings are greatly improved and secure using new generation protection software. This advances the overall functionality and better control.
Improvements such as thermal measurement capabilities, remote I/O modules and remote analog or digital inputs expand the protection and monitoring capabilities of a power system, increasing its life and ensuring personnel safety.
Costs are also significantly reduced because a watchdog need not be on-site to learn about a fault. It can be done remotely and internally, which also protects users from hazards caused by relay failures. The communication capabilities are powered up through a relay upgrade since monitoring is instantaneous and constant.
Having an upgraded protection relay scheme also improves mean time between failures or MTBF. Problem is resolved at the soonest possible time and extends maintenance intervals effectively. Moreover, most all relay upgrades meet IEC 61850 and NERC requirements, guaranteeing their safety, reliability and effectivity.
Basic Steps to Relay Upgrading
Every protection relay upgrade should follow these base steps to determine which type of upgrade is necessary, given that most power systems do not need a change in the protection scheme.
Determine The Current Protection Relay
Reading and identifying the protection relay scheme in place (or lack thereof) is the first step to any upgrade. Single-function devices such as electromechanical relays should be replaced with multifunctional devices to expand control and monitoring capabilities.
Each device is rendered a number that one needs to take note of when upgrading any relay. This is a very important step in determining the relay series after upgrades have been done.
Validate Control Voltage
The relay may not work entirely or smoke up when the control voltage is incorrectly calculated. Most power supplies have a 240 VAC, 120VAC, 125VDC or 48VDC voltage level. Most new relays can handle these voltages but there are unique cases that require a specific number to work.
This is an indispensable step to ensure that the protection relay upgrade is smooth and efficient. Errors in voltage matching can destroy the entire system, causing potential losses to the business.
Determine the CT ratio and Secondary Output Rating
To ensure that the new relay has a proper configuration, current transformer (CT) and its secondary output rating are pieces of data that need to be determined. Incorrect CT ratio may lead to reduced accuracy and therefore compromise the whole system and relay functionality.
CT secondary output current usually is limited between one or five amperes. For example, if the CT ratio is around 600:5, the secondary output rating of the current transformer is five amperes.
Developing the Relay Part Number
Since a relay is a series of devices, determining the relay part number is another essential step to formulating an efficient protection relay scheme that does not hinder or compromise the existing protection.
The first part is to identify the type of protection needed. Here are some of them:Feeder protection: used for buses or cables feeding a load
• Line protection: for underground or overhead power lines
• Transformer protection: specifically used for transformers
• Motor protection: protects conductors that feed the motor and the motor itself
• Differential protection: protects transformers and lines
• Generator protection: used specifically for transformers
It’s important to know that some panels contain more than one protection relay. The device manufacturer can help in determining the device number, but for the most part, it takes a smart engineer to determine what type of relay upgrade works best for the whole system.
Like most upgrades, determining the need for a change and employing such changes should be done professionally in order to protect the system from reduced functionality. Updating protection relay schemes is necessary to keep up with the times, but must be fulfilled carefully and with efficiency in mind.
If you need a dependable service provider that can implement protection relay upgrades, we can help you. To learn more about our services, contact us today.