ASK-43H Transformer Non-Electrical Protection Device

Description

The ASK-43H is a transformer non-electrical protection device designed for oil-immersed transformers. It integrates gas, oil temperature, winding temperature and pressure protection functions to detect internal transformer abnormalities that may not be identified by conventional electrical protection alone.

Usually installed in the same panel with transformer differential protection and transformer backup protection devices.

Key Protection Functions

• Buchholz / gas protection
• Light gas alarm
• Heavy gas trip
• Oil temperature protection
• Winding temperature protection
• Pressure relief / surge protection
• Alarm and trip outputs
• Optional communication interfaces

What Is Transformer Non-Electrical Protection?

Transformer non-electrical protection detects abnormal physical conditions inside or around a transformer rather than relying only on electrical quantities such as current and voltage. Typical functions include gas accumulation, oil temperature, winding temperature and pressure protection.

These functions complement electrical protection such as transformer differential, overcurrent and earth fault protection.

Product Functions of Transformer Non-Electrical Protection Device

Electrical vs Non-Electrical Transformer Protection

Buchholz Gas Protection

Light Gas Protection — 71G-L

Detects gas accumulation associated with developing internal transformer abnormalities and provides an alarm signal.

Heavy Gas Protection — 71G-H

Detects severe internal faults associated with rapid oil movement and provides a trip signal.

Transformer Temperature Protection

Oil Temperature Protection — 26‑O

Winding Temperature Protection — 26‑W

Oil temperature protection monitors transformer oil temperature, while winding temperature protection provides additional protection against excessive winding heating.

Transformer Pressure Protection

The ASK-43H supports pressure relief / surge protection to detect abnormal pressure conditions associated with transformer internal faults and provide an appropriate protection signal.

Protection Function Table

Applications

The ASB-4401H backup protection relay is suitable for a wide range of transformer applications across utility, industrial, and renewable energy sectors.

• Oil-Immersed Power Transformers: Backup protection for phase and earth faults, supporting Buchholz and temperature inputs for comprehensive protection.

• Distribution Transformers: Ideal for 10kV, 20kV, 33kV, 66kV, and 110kV distribution networks — including Buchholz and temperature monitoring integration.

• Substation Transformers: Provides overcurrent, earth fault, and voltage backup protection for substation transformers with SCADA integration capabilities.

• Industrial Transformers: Reliable backup protection for transformers supplying factories, mines, and large industrial facilities.

• Renewable Energy Transformers: Suitable for solar, wind, and hydro applications where transformer protection must coordinate with inverter or generator protection.

• Transformer Protection Panels: Can be integrated into new or retrofit transformer protection panels as a backup protection module alongside primary differential relays.

Key applications include: 33 kV, 66 kV, and 110 kV transformers in utility networks, plus industrial and renewable energy installations requiring coordinated phase/earth fault backup and Buchholz/temperature monitoring.

How Does ASK-43H Work with Electrical Transformer Protection?

The ASK-43H complements electrical transformer protection by monitoring gas, temperature and pressure conditions. It can be installed in the same protection system as transformer differential and backup protection devices.

General Technical Data

Environmental Conditions

• Operating conditions: –20°C to +70°C, relative humidity 5% to 95% (no condensation or freezing inside the unit)
• Storage: –30°C to +80°C. When no excitation is applied at the extreme temperature limits, the device shall not undergo irreversible changes, and it shall function normally once the temperature returns to normal. Packaged devices shall be stored at an atmospheric pressure of 80–110 kPa (equivalent to an altitude of 2 km or less) and a relative humidity of no more than 85%.
• Transportation: -25°C to +70°C, relative humidity not exceeding 85%;

Status Indicator Descriptions

Outline and Installation Dimensions

FAQ