0-100°C or 0-120°C measuring ranges
Select the range that matches the transformer top-oil limits and existing control scheme.
Oil Temperature Indicators manufacturer and supplier
BWY-802/803 Oil Temperature Controller
A transformer top-oil temperature controller with local indication, Pt100 remote signal and adjustable control contacts.
What the BWY-802 / BWY-803 Does
See how this model supports temperature indication, control contacts and remote monitoring.
Pt100 resistance output for remote indication
Send a resistance temperature signal to a compatible remote display or signal converter.
Outdoor IP55 construction with adjustable contacts
Supports outdoor installation and local switching for cooling or alarm circuits.
BWY-802 / BWY-803 Technical Specifications
Use these values to compare models. Request the latest datasheet and drawing for the exact suffix you plan to order.
| Output signal | Pt100 resistance signal |
|---|---|
| Measuring ranges | 0-100°C or 0-120°C |
| Accuracy | Class 1.5; stated maximum error ±1.8°C for 0-120°C |
| Switching error | ±2°C |
| Switch rating | AC 220 V / 3 A; DC 220 V / 1.5 A |
| Operating ambient | -40°C to +55°C; humidity up to 95% |
| Protection grade | IP55 |
| Temperature bulb | Φ14 mm; insertion depth at least 150 mm |
| Mounting thread | M27 × 2 mm |
| Standard capillary | 5 m |
| Optional remote conversion | 0-5 V, 4-20 mA or RS485 through a compatible display |
BWY-802 / BWY-803 Product Overview
The BWY-802 and BWY-803 controllers measure transformer top-oil temperature and provide a Pt100 resistance signal for remote indication. The mechanical pointer and adjustable contacts support local operating checks and cooling control.
A compatible digital display can convert or retransmit the Pt100 signal as a voltage, current or RS485 interface. The final remote architecture should define who supplies excitation, how cable resistance is handled, and where signal conversion occurs.
How the BWY-802 / BWY-803 Measures Temperature
The bulb, capillary and mechanical sensing element form a sealed temperature system. Oil temperature changes move the pointer and the adjustable microswitch mechanism.
The composite sensing arrangement also provides a Pt100 output. This allows the control room to display the temperature without relying on visual inspection of the local dial.
Selecting the Correct BWY-802 / BWY-803
Choose the 0-100°C or 0-120°C range, confirm contact rating and use, Pt100 wiring, capillary length, mounting dimensions and any remote conversion requirement.
For a BWY replacement, send photographs of the nameplate and terminals together with the existing installation drawing.
BWY-802 / BWY-803 Installation and Commissioning
Insert the bulb into the designated top-oil pocket with the required insertion depth. Do not shorten, kink or sharply bend the capillary.
Verify Pt100 loop resistance and receiving-instrument configuration. Test every switch point using the approved commissioning method.
Where the BWY-802 / BWY-803 Is Used
Distribution transformer oil temperature control
Substation remote oil temperature indication
Cooling system switching
BWY-802 and BWY-803 replacement
Related BWY-802 / BWY-803 Selection Resources
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Check available management-system, conformity and qualification materials for procurement review.
Certification and qualification documentsSales and engineering support
Request BWY-802 / BWY-803 Datasheet and Pricing
Tell us the transformer type, required temperature range, contact functions, output signal, capillary length, quantity and destination. We will help you identify a suitable model and send the available technical documents.