TO247 Thick Film Power Resistor

The TO247 Thick Film Power Resistor from RST Electric represents the next step in power resistor packaging, offering significantly higher power handling than traditional TO220 devices while maintaining a familiar, easy-to-mount form factor. Designed for applications where 35W or 50W is insufficient but larger chassis-mount resistors are impractical, this Heatsink Mount Resistor delivers 100W at 25°C case temperature (3.5W without heatsink) in a compact TO247 package. The single-screw mounting interface simplifies mechanical integration, allowing engineers to attach the device directly to a heatsink or chassis using thermal interface materials for optimal heat transfer.

Optimized Architecture

The internal construction of this High-Power Thick Film Resistor is optimized for both electrical performance and thermal efficiency. A high-stability resistive layer is deposited on an alumina substrate, which is then wire-bonded to the lead frame and encapsulated in a rugged molded plastic package. This construction provides exceptional insulation properties, withstanding 1800VAC and maintaining insulation resistance greater than 10GΩ. The non-inductive nature of thick film technology ensures minimal parasitic inductance, making the PRT100 suitable for high-frequency switching circuits and fast transient applications.

Strict scene adaptation

The PRT100 series covers a broad resistance range from 0.2Ω to 1MΩ, with TCR options from ±50 ppm/°C (for precision values >10Ω) to ±300 ppm/°C (for low ohmic or high-resistance ranges). Standard tolerances include ±1%, ±5%, and ±10%, accommodating both high-accuracy instrumentation and general-purpose power applications. With an extended operating temperature range of -65°C to +175°C, this TO247 Resistor is well-suited for harsh environments where reliability is paramount. As a trusted To247 Thick Film Power Resistor manufacturer in China, RST Electric combines over 10 years of thick film engineering expertise with precision manufacturing to deliver components that provide reliable, stable performance in the most demanding power electronic circuits.

Technical Specification

Standard Specification

Electrical Performance

● Lead wire materials: Tinned Copper

● Max torque: 0.9Nm

● Rated power at 25°C of PRT100 is 3.5W without heat sink plate.

● Power limit depends on surface temperature of package.

● Heat dissipating cream must be applied correctly

What are the advantages of our To247 Thick Film Power Resistor compared to those of our competitors?

1.High Power Density – 100W at 25°C case temperature, enabling compact high-power designs without the need for bulky chassis-mount resistors.

2.TO247 Industry-Standard Package – Familiar footprint with single-screw mounting simplifies mechanical integration and thermal management.

3.Extended Temperature Range – Operates from -65°C to +175°C, suitable for harsh industrial, automotive, and aerospace environments.

4.High Voltage Capability – 700V maximum working voltage and 1800VAC dielectric strength ensure safe operation in high-voltage circuits.

5.Wide Resistance Range – From 0.2Ω to 1MΩ in a single series, covering applications from high-current sensing to high-impedance voltage division.

6.Non-Inductive Construction – Thick film technology minimizes parasitic inductance, making it ideal for high-frequency switching and snubber applications.

7.Precision Tolerances – Available in ±1%, ±5%, and ±10% to meet both high-accuracy and general-purpose requirements.

8.Low TCR Options – As low as ±50 ppm/°C for precision values >10Ω, ensuring stable performance across temperature variations.

9.Excellent Insulation – Withstands 1800VAC with insulation resistance >10GΩ, ensuring safety in high-voltage circuits.

10.Rugged Construction – Molded plastic case protects the resistive element from mechanical stress, moisture, and contaminants.

Product Applications

Drawing and Dimensions:

Mode of transportation

To ensure that our resistors are not damaged during the entire transportation process, we have developed a detailed packaging and transportation plan, taking into account both protection and adaptability, to safeguard the product quality comprehensively.

When shipping in bulk, all To247 Thick Film Power Resistors are packaged using anti-static tubes or special trays, precisely fitting the packaging dimensions. This not only effectively prevents the pins from bending or deforming, but also protects the mounting pads from being bumped or worn, avoiding any impact on subsequent installation and electrical performance.

For pin protection, we use foam end caps or plastic molded pads for fixation, ensuring that the pins remain straight at all times. There is no need for subsequent correction by the buyer, which improves the assembly efficiency.

Packaging Service

In addition, we offer customized roll tape packaging services on demand, which are suitable for automated assembly lines and help purchasers enhance production efficiency. Each batch of goods comes with a detailed packing list and inspection certificate attached, facilitating purchasers' verification and acceptance, and ensuring that each To247 Thick Film Power Resistor meets the specification requirements. The shipping methods are flexible and can adapt to different purchase quantities. Small batch orders are sent via international courier services such as DHL, FedEx, and UPS, with fast delivery; medium batch orders are transported by air, balancing delivery time and cost; large batch orders are shipped by sea, significantly reducing transportation costs. It is worth noting that all resistors undergo 100% electrical testing before packaging, with particular focus on verifying the resistance value, tolerance, and sampling TCR verification to ensure that the delivered products meet the standards.

Five Reasons to Choose RST Electric

Well-experienced

With ten years of in-depth development and accumulation, RST Electric has become a preferred partner for global buyers. Its core strength focuses on the exclusive capabilities for high-power scenarios, which distinguishes it from ordinary manufacturers and fully meets the strict purchasing requirements. As a legally certified manufacturer in China, we have been dedicated to the research and production of To247 Thick Film Power Resistors for over 10 years. We are a professional manufacturer in the field of thick film technology, achieving full-process self-control from thick film deposition, laser fine-tuning, component assembly to product inspection. There are no outsourcing links, ensuring the consistency of product quality from the very beginning and eliminating performance deviations caused by process control oversights.

Factory direct supply

The factory direct supply model is one of our core competencies. All resistors are directly shipped from the factory without any middleman markup. The prices are transparent and traceable, allowing buyers to purchase high-quality and high-power resistors at more favorable costs. At the same time, we have an ISO 9001-certified production base equipped with an exclusive To247 Thick Film Power Resistor production line. Each product undergoes 100% electrical testing. We can provide sampling tests in accordance with MIL-PRF-55342 and AEC-Q200 standards based on the purchasing requirements. Our professional engineering team has extensive experience in high-power electronics and thermal management, and can provide targeted technical support to solve various problems in the product integration process for buyers.

Global Cooperation

We have extensive experience in global cooperation and have become a reliable supplier for global power supply manufacturers, automotive electronics enterprises, and industrial control producers. Our products are exported to 40+ countries including Germany, the United States, and Japan. We are well-versed in the standards and requirements of different industries and regions, and can precisely meet the usage requirements of various high-power scenarios.

Support customization

In terms of customized services, we can offer a full range of customization, including 100W and custom power, 0.2Ω to 1MΩ and special resistance values, ±0.5% to ±10% tolerance, multiple TCR options, as well as personalized services such as pin formation and special screening, perfectly meeting the exclusive needs of different buyers.

After-sales service

We offer comprehensive delivery and after-sales guarantees. Standard-sized products can be delivered within 10 to 15 days, while customized products have a delivery period of 15 to 25 days, which can be flexibly adapted to the production plans of the purchasers. Along with the products, we provide complete documents such as test reports, material certifications, RoHS/REACH declarations, etc., to meet the requirements of compliance audits. All products enjoy a 12-month warranty. During the warranty period, we offer remote fault diagnosis, spare parts delivery services, and professional technical teams provide full support for product integration throughout the process, ensuring that the purchasers have no worries throughout the process and truly achieving win-win cooperation.