Marshaling kiosks

Marshaling kiosks, also known as marshaling boxes or marshaling cabinets, are an integral part of power transformers and play a crucial role in their operation and protection. Marshaling kiosks provide convenient connection points for control, protection, and instrumentation systems which are used in substations. This includes DC and AC power, instrument transformers, and switchgear equipment.

1.Marshaling kiosk in a power transformer

A marshaling kiosk in a power transformer is a type of electrical equipment used to distribute power from a transformer to various other electrical devices or systems. It typically includes a series of electrical panels and terminals, which connect and control the flow of power to different parts of the system.

🔧 Purpose of the Marshaling Kiosk

• Provides a neat and organized interface between the transformer and control room/SCADA systems.
• Acts as a junction box for:
  • Control circuits
  • Protection relays
  • Monitoring instruments
  • Signaling devices

Here’s an overview of their functions and components:

2.The function of Marshalling Kiosks in Power Transformer:

1. Control and Monitoring: Marshalling kiosks are used to accommodate control and monitoring devices that enable the operator to manage the power transformer’s operation. This includes items like switches, indicators(OTI and WTI), and meters.
2. Protection and Safety: Power transformers need to be protected from various faults and abnormal conditions. The marshaling kiosk houses protective relays, fuses, and other protective devices to detect and respond to faults, ensuring the transformer is isolated from the system when necessary.
3. Cabling and Termination: The kiosk provides a centralized location for incoming and outgoing power and control cables. It allows for organized cable termination points, making maintenance and troubleshooting more straightforward.
4. Environment and Security: Marshalling kiosks are typically designed to protect sensitive equipment from harsh environmental conditions, such as extreme temperatures, moisture, and dust. They may also have security features to prevent unauthorized access.

3.Components of Marshalling Kiosks:

The specific components housed in a marshaling kiosk can vary depending on the transformer’s size, application, and complexity. However, some common components found in a typical marshaling kiosk include:

1. Control and Monitoring Devices: This includes control switches, push buttons, selector switches, voltage and current indicators, and meters.
2. Protective Relays: Numerical or electromechanical relays are used to detect faults and abnormal conditions in the transformer and its associated systems.
3. Fuses and Circuit Breakers: These are used to protect the transformer and other components from overcurrent conditions.
4. Terminal Blocks: Terminal blocks are used for the organized termination of power and control cables.
5. Wiring and Cabling: The internal wiring connects various devices within the marshaling kiosk and facilitates connections to the transformer and other systems.
6. Cooling and Ventilation: Depending on the design and size, some marshaling kiosks may include ventilation and cooling systems to maintain the temperature within an acceptable range.
7. Instrument Transformers: Current transformers (CTs) and voltage transformers (VTs) may be installed within the marshaling kiosk to provide reduced signals for the protective relays and monitoring devices.
8. Communication Equipment: In modern installations, communication devices such as Ethernet switches or remote terminal units (RTUs) may be integrated to enable remote monitoring and control of the transformer.

🏗️ 4. Installation and Location

• Typically installed close to the transformer, on a pedestal or concrete foundation.
• Weatherproof (IP55 or higher) enclosures for outdoor environments.
• Made from galvanized steel or stainless steel, with anti-condensation heaters.

🧰 5. Advantages of Using a Marshaling Kiosk

• Simplifies commissioning and maintenance
• Provides a clean and organized wiring layout
• Enables safe isolation of control signals during testing
• Improves fault diagnosis through accessible terminals and indicators
• Protects critical connections from environmental hazards

📘 Standards and Guidelines

• IEC 62271 – High-voltage switchgear and controlgear standards
• IEEE C57 – Power transformer protection and accessories
• IS 1180 / IS 2026 – Indian standards for distribution and power transformers

It’s worth noting that the design of marshaling kiosks must adhere to relevant industry standards and local regulations to ensure the safety and reliability of transformer installations. Additionally, they may vary significantly depending on the specific requirements of the overall substation design.