BWR-04 / BWR-06 Transformer Winding Temperature Controller Type 1 with 4-20mA Output

Product Overview

The BWR-04 / BWR-06 Transformer Winding Temperature Controller Type 1 is a dedicated temperature control instrument for oil-immersed transformer winding temperature monitoring, local indication and protection control. The product is designed based on the additional temperature rise principle. It detects the transformer top oil temperature and combines it with the additional temperature rise generated by load current, so as to simulate and indicate the transformer winding hot-spot temperature.

This series can output various control and transmission signals for background monitoring systems, secondary instruments, PLC, DCS or SCADA systems. It features clear indication, convenient installation, simple wiring, stable operation and easy maintenance. It is widely used in power transformers, oil-immersed transformers, substations, distribution rooms, industrial power distribution systems and electrical switchgear equipment.

Working Principle

The temperature bulb of the winding temperature controller is installed in the top oil pocket of the transformer tank to detect the top oil temperature. When the transformer is under no-load condition, the indicated temperature mainly reflects the transformer oil temperature.

When the transformer operates under load, the load current taken from the current transformer flows through the internal heating element of the temperature controller after proper adjustment. The heating element generates an additional temperature rise. Therefore, the indicated temperature is determined by both the top oil temperature and the additional temperature rise caused by load current, which helps simulate the winding temperature of the transformer.

Main Functions

1. Winding Temperature Monitoring
   Used to monitor the operating temperature of oil-immersed transformer windings and assist in evaluating transformer load condition and operating safety.
2. Local Temperature Indication
   Provides clear on-site temperature display for inspection, recording and maintenance.
3. 4-20mA Remote Output
   Supports standard 4-20mA analog signal output for connection with PLC, DCS, SCADA and background monitoring systems.
4. Temperature Alarm Control
   Outputs alarm signals when the temperature reaches the preset alarm value, helping operators respond in time.
5. Cooling Fan Control
   Controls the start and stop of transformer cooling fans according to temperature changes, improving heat dissipation efficiency.
6. Trip Protection
   Can be connected with trip protection devices when the winding temperature exceeds the safe limit, reducing the risk of overheating and transformer failure.
7. Remote Monitoring
   Can be integrated with automation monitoring systems for remote data acquisition, transmission and centralized management.

Technical Specifications

Measuring Range: 0℃ to 150℃, customizable according to user requirements
Accuracy Class: 2.0
Ambient Temperature: -40℃ to +55℃
Relative Humidity: <95%
Switch Performance: Each switch can be freely set within the full measuring range
Switch Action Error: ±2℃
Switch Differential: 6±2℃
Switch Rated Capacity: AC220V / 5A
Insulation Test: 2000V to ground, 50Hz, 60 seconds
Temperature Bulb Size: Φ14 × 150mm
Mounting Thread: M27 × 2
Cable Outlet Size: M20 × 1.5, standard Φ15 hose connector, optional Φ20 hose connector
Capillary Length: 6m, maximum customizable length 18m
Protection Grade: IP55
Overall Dimension: 304mm × 192mm × 153mm
Mounting Dimension: 100mm × 80mm or 210mm × 144mm

Performance Features

1. High-frequency welding process ensures reliable sealing and prevents leakage.
2. Mechanical fatigue-resistant structure for long-term stable operation.
3. Multiple output signal options with stable signal transmission.
4. Built-in temperature transmitter with photoelectric isolation, isolation voltage up to 2000V.
5. Lightning protection circuit design, suitable for areas with frequent lightning.
6. Mechatronic integrated design with compact structure and easy maintenance.
7. Special dual bellows structure reduces the influence of ambient temperature changes on indication accuracy.
8. The error between the instrument body and the background monitoring system is less than ±2℃.
9. The instrument can be maintained without power shutdown.

Model Description

BWR stands for Transformer Winding Temperature Controller.

04: Four adjustable switches
05: Five adjustable switches
06: Six adjustable switches

Function Code:

B: DC24V power supply, 4-20mA output
J: AC220V power supply, 4-20mA output
JJ: AC220V power supply, dual 4-20mA output
Y: Resistance signal output
A: Pt100 signal output
AJ: Pt100 signal and 4-20mA signal output
AA: Dual Pt100 signal output

Protection Condition:

TH: Humid tropical protection
TA: Dry tropical protection
T: Dry and humid tropical protection

Applications

The BWR-04 / BWR-06 Transformer Winding Temperature Controller Type 1 is suitable for:

Power transformers
Oil-immersed transformers
Substations
Distribution rooms
Power distribution systems
Industrial electrical equipment
Electrical switchgear equipment
Transformer cooling control systems
Transformer temperature protection systems
Remote temperature monitoring systems

Applicable Industries

Power industry
Transmission and distribution industry
Substation construction
Industrial automation
Energy infrastructure
Electrical equipment manufacturing
Power operation and maintenance systems

Product Application

The BWR-04 / BWR-06 Transformer Winding Temperature Controller Type 1 is mainly used for temperature monitoring, indication, alarm, cooling control and safety protection of oil-immersed transformer windings. With local indication and 4-20mA remote signal output, it helps users monitor transformer operating conditions, improve operation safety and enhance maintenance efficiency.