Overview: The document is a comprehensive guide from Ohmite Manufacturing Company, detailing their range of resistive products, specifically focusing on the Component Selector 4000G. It includes specifications, product series, and historical context of the company.

Specifications: The document lists various resistor series, including MIL Spec Ohmite Series, with detailed part numbers and wattage ranges. It covers different types of resistors such as wirewound, thick film, and ceramic composition, highlighting their applications in high current, high voltage, and high energy environments.

Procedures and Standards: Ohmite products are designed to meet military specifications and are tested using government-approved equipment. The document outlines the company's commitment to RoHS compliance, indicating that both compliant and non-compliant products will be stocked to meet diverse customer needs.

Recommendations: The document advises using Ohm’s Law to calculate maximum working voltage for each resistance value. It also emphasizes the importance of selecting the right resistor for specific applications, considering factors like voltage, current, and energy requirements.

Company History and Mission: Ohmite has been a leader in resistive products for over 80 years, evolving with the electronics industry. The company aims to exceed customer expectations through quality service and innovative solutions, supported by a global network of distributors.

Terms and Conditions: The document includes standard payment terms, return policy, and warranty information, emphasizing that product specifications may change without notice.

Specifications
Operating Temperature: 5°C to 200°C
Resistance Range: 1KΩ to 100GΩ
Resistance Tolerance: ±1% standard; 5% for HVF1206 100MΩ-10GΩ; 10% for 10GΩ+
Temperature Coefficient: ±100ppm standard
Coating: Silicone
Solder Pad Material: Silver (PdAg)
Note: Use only silver-based solder compositions. Avoid corrosive solder fluxes.

Procedures and Recommendations
Ensure PCBs are cleaned to remove moisture layers containing halides. Use halide-free solder pastes like ROL0. Provide a slot or air gap under the resistor element to increase insulation resistance and reduce capacitive coupling.

Performance Data
Insulation Resistance: >10,000 MΩ at 500 Volt, 25°C, 75% relative humidity
Dielectric Strength: >1,000 Volt at 25°C, 75% relative humidity
Thermal Shock: ∆ R/R < 0.1% typical, 0.50% max.
Overload: ∆ R/R < 0.1% typical, 0.50% max.
Moisture Resistance: ∆ R/R < 0.1% typical, 0.50% max.
Load Life: ∆ R/R < 0.1% typical, 0.50% max.

Ordering Information
Series: HVF1206, HVF2512
Tolerance: F = 1%, G = 2%, J = 5%
Ohms: First 3 digits are significant; last digit specifies number of zeros.
Taping Code: T = tape & reel
RoHS Compliant

Derating and Tape & Reel Specifications
Derating: 100% at 70°C, derates linearly to zero at 125°C
Tape & Reel: Per EIA Std. RS-481

Voltage Coefficient of Resistance
1206 Series: 1K ..10MΩ <3.20 ppm/V, 10M ..100MΩ <15.00 ppm/V
2512 Series: 1K ..30MΩ <0.80 ppm/V, 30M ..300MΩ <4.00 ppm/V

Features
High-value chip resistors in thick film technology
Low temperature and voltage dependency
High working voltage up to 3000V
Suitable for high vacuum applications
Contact areas: Nickel-barrier/matte tin
Wraparound terminals

Applications
Switching Power Supplies, Cellular, Telecom and Wireless, Computer, RF

Overview: The document provides detailed technical specifications and ordering information for various series of current sense resistors manufactured by Ohmite. These include the LVK Series, FCSL Series, MCS Series, and Mini Macro Chip Series, each designed for specific applications in current sensing with varying power ratings, resistance ranges, and temperature coefficients.

LVK Series: This series features four-terminal high precision current sense resistors with a Kelvin configuration for accurate current measurement. The resistors are available in different sizes (LVK12, LVK20, LVK24, LVK25) with power ratings from 0.5W to 2.0W and resistance ranges from 0.001Ω to 0.05Ω. They are designed for automatic insertion and have a temperature coefficient of resistance (TCR) of 50ppm for most models, with LVK25 offering up to 300ppm based on resistance value.

FCSL Series: These metal foil current sense resistors offer low and stable TCRs and are available in power ratings up to 5 Watts. The series includes models FCSL64, FCSL76, FCSL90, and FCSL110, with resistance values ranging from 1mΩ to 100mΩ. They are designed for high heat resistance and low electromotive force applications.

MCS Series: This series uses metal alloy technology for ultra-low resistance values (0.005Ω to 0.05Ω) and is available in 1W and 2W power ratings. The resistors feature a low TCR and are suitable for industrial and power electronics applications.

Mini Macro Chip Series: These high voltage thick film SMD chips are available in smaller package sizes with high voltage ratings. They offer resistance ranges from 47Ω to 51MΩ and are designed for applications requiring high voltage isolation and low cost.

Performance Characteristics: The document outlines various test conditions and maximum resistance changes for each series, including temperature ranges, solderability, endurance, and resistance to soldering heat. Each series is designed to withstand specific environmental and operational conditions, ensuring reliability and performance in various applications.

Ordering Information: Detailed ordering codes are provided for each series, specifying case sizes, tolerance levels, resistance values, and packaging options. All products are RoHS compliant, ensuring they meet environmental and safety standards.

Overview: The document provides detailed specifications and features of Ohmite's MacroChip resistors, which are designed for high voltage and high resistance applications in surface mount technology. These resistors are suitable for use in medical instrumentation, power supplies, avionics, and light magnification systems.

Applications: The resistors are used in medical instrumentation, power supplies, avionics, and light magnification systems.

Performance Data: The document includes performance characteristics such as humidity resistance, dielectric withstanding voltage, insulation resistance, thermal shock, load life, and resistance to solvents, all tested according to MIL-STD-202 standards.

Ordering Information: The document provides a detailed guide on how to order MacroChip resistors, including series, terminal style, tolerance, coating, and ohms specifications.

Packaging Specifications: Details on tape and reel packaging dimensions are provided for different series of resistors.

Additional Information: The document also includes information on the 60S Series Surface Mount Metal Plate Current Sense resistors, highlighting their features, applications, and performance characteristics.

Package Outline Dimensions and Land Pattern:
The document provides detailed dimensions for various package types (BA, CA, CB, DA, DB, EA, BB) in both inches and millimeters. It includes specifications for parameters such as length, width, and height, along with nominal and reference values. Specific notes mention the availability of pedestal or recessed bases for certain packages and test point specifications.

Tape and Reel Dimensions:
Reel dimensions are compatible with major pick-and-place machines, adhering to EIA 481 A standards, except for the EA size which has a different component pitch. The document lists tape sizes, reel diameters, and quantities per reel for different package sizes.

Temperature Rise and Safe Operating Conditions:
The document includes a graph showing temperature rise data for different substrate materials (FR4 and Alumina) and trace widths. Safe operating temperature rises are specified as either 100°C substrate temperature rise or 180°C package hot spot temperature rise at 25°C ambient.

Performance Data:
Performance characteristics for various resistor types (Carbon/Ceramic Composition, Metal Film, Wirewound, Power Film, Wirewound Non-inductive) are provided, including tolerance levels for temperature cycling, load life, immersion, and overload conditions. All models are rated for no visible leaching and thermal shock resistance.

Standard Part Numbers and Ordering Information:
The document lists standard part numbers for surface mount power resistors, detailing component types, wattage, base type, package size, resistance values, and tolerance levels. Examples of part numbers and their configurations are provided.

Specifications for RW1/RW2 Series:
Features include low resistance, high precision tolerance, low T.C.R., and flameproof rating. Specifications cover power rating, resistance range, tolerance, dielectric withstanding voltage, and TCR. Dimensions for RW1S0CK and RW2S0DK are detailed, along with derating and surface temperature rise information.

Typical Schematic and Performance Characteristics:
The document includes a schematic for input detecting circuits and outlines performance characteristics such as resistance tolerance, T.C.R., overload, resistance to solder heat, rapid temperature change, and moisture resistance.

Overview: This document provides technical specifications and ordering information for various series of resistors manufactured by Ohmite Mfg. Co. It includes details on endurance, temperature operations, material specifications, performance characteristics, and ordering codes for different resistor series.

Overview: This document provides technical specifications and features of Ohmite's current-sense resistors, focusing on the 10 Series and 60 Series. These resistors are designed for low-resistance applications requiring high accuracy and temperature stability, utilizing a Kelvin configuration for improved performance.

Ordering Information: The document provides detailed part numbers and specifications for various resistor models, including their wattage, resistance, tolerance, and dimensions.

Applications: These resistors are suitable for computer, communications, and industrial applications where cost, quality, and reliability are key considerations.

Specifications
Ohmite's resistors are designed with various specifications to meet different application needs. The materials used include flameproof proprietary Centohm coating, ceramic core, and copper-nickel or nickel-chrome alloy elements. The end caps are made of stainless steel, and terminals are tinned copper weld. The resistors are RoHS compliant with a solder composition of 96% Sn, 3.5% Ag, and 0.5% Cu. The derating is linear from 100% at +25°C to 0% at +350°C. Electrical tolerance is ±5% standard, with options down to 0.1%. Power ratings are based on a 25°C free air rating, with overload capabilities of 5 to 10 times the rated wattage for 5 seconds. Temperature coefficients vary based on resistance values.

Features
The resistors offer high power dissipation up to 13W at 25°C, are designed for repetitive pulse loading, and have corrosion-resistant terminals for long life. They also provide superior vibration resistance and adhere to the IEC 115-1 reference standard.

G Series Specifications
The G Series capacitors have a temperature range of -55°C to 200°C, terminal strength greater than 25N, and a derating from 25°C to 350°C. The temperature coefficient of resistance (TCR) is ±100 ppm/°C, with tolerances of 1%, ±2%, ±5%, and ±10%. Performance data includes endurance at full rated power for 1000 hours, short-term overload, damp heat, steady state, and climatic sequence tests, all adhering to IEC standards.

Ordering Information
Ordering involves specifying the series, wattage, resistance value, tolerance, and compliance with RoHS standards. The G Series uses a component modifier 'W' for wirewound, with wattage options of 10 and 13 watts. Resistance values are denoted with 'R' for decimal and 'K' for 1,000. Tolerances are indicated by 'K' for 10%, 'J' for 5%, 'G' for 2%, and 'F' for 1%.

HS/HSN Series
The HS/HSN Series offers greater power capacity (100 and 250 watts) with standard and non-inductive winding options. They feature molded construction for environmental protection, complete welded construction, and are designed for chassis mounting to utilize heat-sink effects. The series is RoHS compliant.

Metalohm Series
The Metalohm Series features cold-rolled steel encased wirewound resistors with heatsinkable radial terminals. They are flameproof, have a higher power rating due to heat sink capacity, and are nonhygroscopic. The series offers various terminal styles and dielectric strengths, with options for noninductive versions and terminal sleeves to increase dielectric strength.

Specifications:
The document outlines specifications for various resistor series, including material composition, electrical properties, and physical dimensions. The core material is ceramic, with a vitreous enamel coating for most resistors, except those above certain resistance values which use silicone-ceramic coatings. Terminals are solder-coated radial, and the resistors are RoHS compliant.

Electrical Properties:
Resistors have a tolerance of ±5%, with power ratings based on a 25°C free air rating. Overload capacities are specified for different wattages, and the temperature coefficient is ±260 ppm/°C. The document provides formulas for calculating maximum current.

Procedures and Recommendations:
Resistors with values above 3.9K (3W) and 8.2K (5W) involve fine resistance wire and should not be used in critical applications without burn-in and/or thermal cycling. Derating is linear from 100% at +25°C to 0% at +350°C.

WFH Series Specifications:
The WFH series includes aluminum housed wirewound power resistors with power ratings from 90W to 330W. They feature solder, wire, and "Fast-On" terminations, with custom wire lengths available. The series is designed for superior thermal transfer and does not require heat sink compound due to a large mounting surface.

Thermal Resistance:
The document provides thermal resistance values for different measuring points in the WFH series, with equations for designing resistors at stationary load.

SH Series Specifications:
The SH series includes precision metal-clad shunts designed for high load capacity and accuracy. They are suitable for precise current measurements and feature a four-terminal technique for easy installation.

Brown Devil® 200 Series:
This series features small, durable power resistors with a vitreous enamel coating. They are designed for high-temperature performance and have a hollow-core construction for rigid mounting.

Ordering Information:
The document provides detailed ordering information for each series, including part numbers, ohm values, wattage, and tolerance options. It also highlights RoHS compliance and availability checks through the manufacturer's website.

Overview: This document provides technical specifications and details for Ohmite's range of resistors, including the 210, 250, and 270 series. These resistors are designed for high wattage applications and feature various coatings and configurations to suit different needs.

Applications: These resistors are suitable for adjusting circuits, obtaining odd resistance values, and setting equipment to meet various line voltages. They are ideal for rugged applications due to their durable construction and coating.

Ordering Information: The document provides detailed part numbers and configurations for ordering, including options for custom core and terminal selections.

Overview
The document provides detailed specifications and features of various series of ceramic housed radial and axial terminal power resistors manufactured by Ohmite. These resistors are designed for commercial applications where cost efficiency and space savings are critical.

Series and Specifications

• TWW Series: Ceramic housed wirewound radial resistors available in wattages of 3, 5, and 10 watts, with resistance ranging from 0.01 to 990 ohms. They have a dielectric withstanding voltage of 1,000VAC and can handle short time overloads of 10x rated power for 5 seconds.
• TWM Series: Ceramic housed metal oxide radial resistors with wattages of 3, 5, and 10 watts, offering resistance from 43 ohms to 50K ohms. They also have a dielectric withstanding voltage of 1,000VAC and can handle short time overloads of 5x rated power for 5 seconds.
• TUM/TUW Series: Ceramic housed axial terminal resistors available in wattages from 3 to 15 watts, with resistance values ranging from 0.01 to 150K ohms. These resistors are also designed to withstand a dielectric voltage of 1,000VAC.

Features

• Economical commercial grade suitable for general-purpose use.
• Available in wirewound and metal oxide constructions.
• Flameproof inorganic construction ensures safety.
• Wide resistance range to accommodate various applications.

Derating and Performance
The document includes derating curves for the resistors, indicating how the power rating decreases with increasing ambient temperature. The resistors are designed to operate within a temperature range of -55°C to 275°C.

Ordering Information
Resistors are identified by a part number that includes series, wattage, tolerance, and resistance value. The document provides examples of part numbers and their corresponding specifications.

High Energy Wirewound Resistors
Ohmite also offers high energy wirewound resistors in axial, surface mount, and heat sinkable packaging. These resistors are designed to maximize joule ratings and fusing currents, with specific part numbers provided for different power and resistance values.

Conclusion
Ohmite's range of resistors is designed to meet the needs of commercial applications requiring cost-effective and space-efficient solutions. The document provides comprehensive specifications and ordering information to assist in selecting the appropriate resistor for specific applications.

Overview: The document provides detailed technical specifications and ordering information for Ohmite's PFE and PFR Series Powr-Rib® Edgewound and Round Wire resistors. These resistors are designed for high power applications, handling between 700 to 1000 watts, with special orders up to 1600 watts.

Design and Construction: The resistors are constructed with a heavy resistance alloy mounted on ceramic insulators, supported by a metal mounting bracket. Metal parts are heavily plated to prevent oxidation and corrosion. Edgewound units feature clamp-type terminals for reliable connections.

Ordering Information: The document includes a part number chart for standard resistance values. Edgewound and Round Wire designs are available, with specific part numbers and specifications listed for each.

Additional Features: The document also mentions the availability of special engineering services for custom ohmic values, mountings, and terminal styles.

Applications: The resistors are suitable for dynamic braking, load banks, motor starting, and plugging, with high current round edgewound resistors available for transit use.

Overview: The document provides detailed specifications and features of Ohmite's Power Chip® resistors, including the TA, TAH, TBH, and TCH series. These resistors are designed for high power density applications and are suitable for various industrial uses.

TA Series:

• Specifications: Thick film on alumina substrate, high power density, low inductance, and wide resistance range. Power ratings range from 3W to 100W.
• Features: High-temp terminal construction, easy installation, and convection cooling.
• Applications: Power supplies, audio amplifiers, and power control applications.

TAH Series:

• Specifications: 20W power rating, low inductance, and high pulse tolerance. Resistance range from 0.05Ω to 10KΩ.
• Features: Electrically isolated from heat sink, quick-snap molded package.
• Applications: Frequency conversion, high-frequency balancing, and snubbers.

TBH Series:

• Specifications: 25W power rating, non-inductive performance, and low thermal resistance. Resistance range from 0.03Ω to 10KΩ.
• Features: Economically priced, electrically insulated from metal heat sink.
• Applications: Power supplies, industrial controls, and automotive steering.

TCH Series:

• Specifications: 35W power rating, very low inductance, and low thermal resistance. Resistance range from 0.1Ω to 10KΩ.
• Features: Single screw mounting, low thermal resistance to heat sink.
• Applications: Switching power supplies, snubbers, and voltage regulation.

General Specifications:

• Material: Alumina substrate, thick film resistor, glass coating, solder plated phosphor bronze terminals.
• Electrical: Tolerance options of ±1%, ±5%, and ±10%. Maximum operating voltage varies by series.
• Thermal: High thermal conductivity and temperature coefficient specifications.

Ordering Information: Part numbers are structured to indicate series, tolerance, package type, resistance value, and pin spacing. RoHS compliance is noted.

Specifications:
1. Dielectric Strength: 1800 VAC
2. Insulation Resistance: Minimum 10GΩ
3. Momentary Overload: 2x rated power for 5 seconds, voltage ≤1.5 times continuous operating voltage, ∆R ±(0.3% + 0.01Ω) max
4. Terminal Material: Copper
5. Terminal Plating: Lead-Free Solder (97% Tin, 3% Silver)
6. Maximum Torque: 0.9 Nm
7. Power Rating: 35 Watts at 25°C case temperature
8. Working Temperature Range: -55°C to +175°C
9. Solder Process: Maximum 260°C for 10 seconds

Test Data:
1. Load Life: MIL-R-39009, 2000 Hours @ Rated Power, ∆R = ±(1.0% + 0.01Ω)
2. Thermal Shock: MIL-R-STD-202, Method 107, Cond. F, ∆R = ±(0.3% + 0.01Ω) max
3. High Frequency Vibration: MIL-R-STD-202, Method 204, Cond. D, ∆R = ±(0.2% + 0.01Ω) max
4. Terminal Strength: MIL-R-STD-202, Method 211, Cond. A, ∆R = ±(0.2% + 0.01Ω) max (Pull Test) 2.4N
5. Moisture Resistance: MIL-R-STD-202, Method 106, ∆R = ±(0.5% + 0.01Ω) max

Standard Part Numbers:
Various part numbers are listed with different ohm values and tolerances. Example: 2R40 = 2.4 Ohms, 2K40 = 2400 Ohms.

Derating Curve:
The power rating decreases linearly from 100% at 25°C to 0% at 150°C.

Features:
1. Power Rating: 35 Watt at 25°C
2. Package: SMD - DPAK configuration
3. Heat Resistance: Rth <4.28°C/W
4. Environmental Protection: Molded case
5. Electrical Insulation: Resistor element insulated from metal sink tab

Ordering Information:
Includes part numbers, ohm values, and tolerance options. RoHS compliant versions are available.

Usage Recommendations:
Designed for use with proper heatsinking. Maximum base plate temperature must be monitored to establish power rating. A thermocouple should be attached to the side of the base plate for accurate temperature measurement.

Specifications
1. Material: Resistor made of thick film on alumina, lead is solder-coated phosphor bronze, and solder is 100% Sn. The case is high-temperature plastic.
2. Electrical: Resistance range from 2Ω to 10KΩ, maximum working voltage of 500V or limited by Ohm’s law, thermal resistance of 1.47°C/W, and temperature coefficient varies with resistance.
3. Insulation Resistance: 400MΩ.
4. Short Time Overload: 2x rated power, not exceeding 1500V.
5. Derating: Linear from 100% at 25°C to 0% at 150°C.

Procedures and Recommendations
1. Heatsinking: Proper heatsinking is essential. The maximum base plate temperature must be monitored and kept within specified limits. A thermocouple should be attached to the side of the base plate for accurate temperature measurement.
2. Mounting: The product is designed for direct mounting onto a heatsink, and the use of a thermal transfer compound with a heat conductivity better than 1W/mK is recommended for optimal performance.

Performance Data
1. Load Life: 1000 hours at rated power with a maximum resistance change (∆R) of ±1%.
2. Moisture Resistance: Complies with MIL-STD-202, method 106, with a maximum ∆R of ±0.5%.
3. Thermal Shock: Complies with MIL-STD-202, method 170, condition F, with a maximum ∆R of ±0.2%.

Standard Part Numbers
Various part numbers are available for different resistance values and configurations, including both P-type (three-terminal) and M-type (two-terminal) versions.

Additional Features
1. RoHS Compliance: The design is RoHS compliant.
2. Non-Inductive Design: Suitable for high-frequency and pulse-load applications.
3. Configurations: Available in different configurations for specific applications, such as current sensing and high power.

Overview: The document provides detailed specifications and features of various heatsink series offered by Ohmite, including the C Series, AH Series, E Series, F and R Series, and M Series. These heatsinks are designed for different electronic packaging needs, focusing on high performance, cost-effectiveness, and compact design.

C Series Heatsinks: This series is designed for TO-247, TO-220, and TO-264 packages. Key features include a camming clip system for easy assembly, maximum thermal transfer, and design flexibility. The heatsinks are made from Aluminum Alloy 6063-T5 and are available with either a degreased or black anodized finish. The series offers various part numbers with different dimensions and finishes.

AH Series Heatsinks: These extrusion heatsinks come in various profiles and finishes, with options for modifications like screw holes and bolt patterns. They are made from Aluminum Alloy 6063-T5 and are designed for natural convection with a black anodized finish. The series includes a wide range of dimensions and thermal resistance values.

E Series Heatsinks: Designed for TO-220 devices, these heatsinks offer vertical through-hole PCB mounting and are available in black anodized or degreased finishes. They are made from Aluminum 6063-T5 and feature solder feet made from tin-plated brass. The series provides different heights and thermal resistance values.

F and R Series Heatsinks: Suitable for TO-218, TO-220, and TO-247 devices, these heatsinks are designed for vertical mounting with solderable pins. They are made from 6063-T5 aluminum with a black anodized finish. The series offers various heights and thermal resistance values, with part numbers indicating the specific configurations.

M Series Heatsinks: This series features a patented design with a matrix clip system for TO-247 and TO-264 packages. It emphasizes ease of assembly, large surface area, and compact footprint, making it ideal for high power density applications.

Conclusion: Ohmite's range of heatsinks provides versatile solutions for thermal management in electronic devices, with options tailored to different package types and performance requirements. The document highlights the importance of selecting the appropriate heatsink based on specific application needs, considering factors like thermal resistance, material, and finish.

Specifications
1U or 2U electronic packaging with forced convection cooling includes components such as heat sinks made from Aluminum Alloy 6063-T5 or equivalent, available in degreased or black anodized finishes. Spring clips are made from music wire per ASTM A228 with bright nickel plating, and solder feet are made from cold-rolled steel per ASTM A-366 with pure tin over copper strike, ensuring RoHS compliance. For improved thermal resistance, the use of thermal joint compound or 0.005 Grafoil (TGon 800 by Laird) is recommended. Electrical isolation can be achieved using Sil-Pad 900S by Bergquist or equivalent.

Heat Dissipation
The document provides standard part numbers for the M Series, detailing the heat dissipation capabilities for two devices. The thermal resistance from case to ambient is illustrated in graphs, showing the relationship between heat dissipated and air velocity.

Features
The design minimizes assembly cost and labor by eliminating the need for mounting holes and fasteners. It maximizes thermal transfer with efficient cooling fins and consistent mounting force, ensuring maximum repeatability and reliability. The design also offers flexibility for dynamic device locations and power upgrading.

Ordering Information
Part numbers are provided for various configurations, including MV-102-55E and MA-102-55E, with details on thermal surface area, weight, and thermal resistance.

W Series Heatsinks
The W Series features a unique design with a patent-pending integral spring clip and extruded aluminum heat sink body, suitable for TO-220 and TO-247 packages. These heat sinks offer reduced assembly cost, maximum repeatability, and resistance to shock and vibration.

S Series LED Heatsinks
These are low-cost, easy-to-assemble heat sinks for "Star" LED packages, available in degreased or black anodized finishes. They can be used in natural or forced convection cooling applications.

TL Series Modular Heat Sinkable Thick Film Power Resistors
The TL Series offers heat sinkable options with thick film resistors, featuring low inductance, in-line mounting profiles, and various power and resistance ranges. Specifications include material details, electrical properties, and thermal resistance values.

Ordering Information
The document provides detailed ordering information for Ohmite's TAP600, TAP800, TAP1000, and TAP2000 series of heat sinkable planar resistors. These resistors are designed for various power applications, including power conditioning, transmission, and control.

TAP600 Series
The TAP600 series offers 600 watts of power and is suitable for liquid or air-cooled heat sink systems. Key features include dielectric strength up to 12KV, low inductance and capacitance, and high insulation resistance. The resistors are encapsulated with a resin-filled epoxy casing. Specifications include resistance values from 0.25Ω to 100KΩ, a power rating of 600W at 70°C, and an operating temperature range of -55°C to +150°C.

TAP800 Series
The TAP800 series dissipates 800 watts and is also designed for use with heat sink systems. It features high alumina content ceramic for optimal heat transfer and low inductance. Specifications include resistance values from 0.25Ω to 10KΩ, a power rating of 800W at 85°C, and an operating temperature range of -55°C to +150°C.

TAP1000 and TAP2000 Series
These series provide 1000W or 2000W of continuous power with proper heat sinking. They are suitable for power conditioning, distribution, conversion, and control. Features include high energy rating, low inductance, and high dielectric strength. Specifications include resistance values from 0.5Ω to 1000Ω and a power rating at 85°C.

TFS Series
The TFS series is designed for surge protection applications, offering non-inductive performance in a compact package. It is ideal for medical surge protection and other high-energy applications. Specifications include resistance values from 100Ω to 100KΩ and an operating temperature range of -55°C to +200°C.

Performance Data
Performance data for each series includes test methods and typical results for short time overload, humidity steady state, temperature cycling, shock, vibrations, and load life. The document emphasizes the importance of proper heat sinking techniques to ensure optimal performance and power rating.

Specifications:
The document outlines the specifications for Ohmite's Slim-Mox resistors, which are precision thick film planar resistors. These resistors are designed for high voltage applications with a resistance range from 100 Ohms to 5,000M Ohms, power ratings from 0.25W to 9.0W, and voltage ratings from 1.5KV to 25KV. They feature low temperature coefficients for high stability and are available with tolerances from 0.5% to 20%.

Features:
Slim-Mox resistors are characterized by high dielectric and low outgassing epoxy coating, low resistor noise, non-inductive properties, and RoHS compliance. They are available with radial terminals and are suitable for applications such as HV power supplies, medical instrumentation, current pulse limiters, and ionization chambers.

Standard Part Numbers:
The document provides a detailed table of standard part numbers for the TFS series, listing various resistance values, tolerances, and power ratings. It includes part numbers for different energy ratings ranging from 6 Joules to 55 Joules.

Applications:
Slim-Mox resistors are used in high voltage power supplies, medical instrumentation, and other applications requiring stable performance across a wide range of resistance values.

Temperature and Voltage Coefficients:
The document includes performance characteristics such as temperature and voltage coefficients of resistance, with specific values provided for different resistor series and temperature ranges.

Contact Information:
For custom configurations and further inquiries, Ohmite provides contact details including phone numbers and a website for product availability and specifications.

Overview: The document provides detailed specifications and applications for various high voltage and high resistance components, including resistors and rheostats, suitable for industrial applications. These components are designed for high voltage switching, industrial control, and current limiting.

Features: The components feature wide resistance ranges, high voltage ratings up to 50KV, and power ratings up to 12.5 watts. They are available with silicone or epoxy coatings.

Applications: These components are used in high voltage power supplies, power distribution, medical instrumentation, avionics, power transmitters, pollution control systems, and industrial control systems.

Specifications:

• Material: Core made of alumina or ceramic, with thick film resistors and RoHS compliant solder terminals.
• Electrical: Resistance ranges from 250Ω to 1 Teraohm, power ratings from 2.0W to 12.5W, and voltage ratings from 10KV to 50KV. Operating temperatures range from -55°C to +210°C.
• Temperature Coefficient: 25ppm/°C from 0° to 85°C, with options for higher temperature coefficients.

Product Series:

• Maxi-Mox Series: Offers precision thick film axial terminal resistors with high voltage and resistance capabilities.
• Power-Mox Series: Features precision power thick film high voltage/high resistance tubular dividers, suitable for high voltage industrial applications.
• SLIM-MOX and MINI-MOX Kits: Provide high resistance and stability for electrometer circuits and ultra-high vacuum applications.

Performance Data: The components are tested for humidity, dielectric withstanding voltage, insulation resistance, thermal shock, load life, resistance to solvents, terminal strength, shock, vibration, power conditioning, and solderability, following MIL-STD-202 standards.

Ordering Information: The document provides detailed ordering codes for specifying the desired product features, including series, terminal type, style, tolerance, coating, and resistance values.

Rheostats: The document also includes specifications for wirewound rheostats, detailing their power ratings, resistance ranges, and mechanical dimensions.

Overview: The document provides detailed specifications and features of Ohmite Power Tap Switches, which are high-power rotary switches designed for dependable and convenient operation. These switches are suitable for handling high currents and are constructed with ceramic arc-proof bodies and metal alloy contacts.

Additional Information: The document includes a table with part numbers, ratings, and dimensions for various models, emphasizing the mechanical and operational integrity of the switches. For product availability, users are directed to check the Ohmite website.

Introduction
This document provides detailed guidelines on selecting and applying resistors, focusing on the importance of accurately determining wattage to prevent overheating and ensure optimal performance.

Resistor Facts and Factors
Resistors are devices that introduce a specified resistance in an electrical circuit, measured in ohms. According to Ohm's Law, the current through a resistor is directly proportional to the voltage across it and inversely proportional to the resistance. The passage of current generates heat, which raises the resistor's temperature. Resistors are rated to dissipate a specific wattage without exceeding a standard "hot spot" temperature.

Selection Process
The selection of a resistor involves three steps:

1. Determine the resistance and the watts to be dissipated using Ohm's Law.
2. Determine the proper "Watt Size" based on watts, volts, permissible temperatures, mounting, and circuit conditions.
3. Choose the most suitable type of resistor, including terminals and mounting.

Power Rating and Physical Size
The "Free Air Watt Rating" is the wattage rating under standard conditions. It is crucial to consider factors like ambient temperature, enclosure, grouping, altitude, pulse operation, cooling air, and limited temperature rise when determining the power rating. The maximum permissible operating temperature is determined by the materials used in the resistor's construction.

Temperature Distribution
The temperature rise along a resistor varies, with the hot spot typically at the center-top. The "Free Air Watt Rating" is used regardless of the resistor's position.

Application Watt Rating
Several factors affect the application watt rating, including ambient temperature, enclosure, grouping, altitude, pulse operation, cooling air, and other considerations like high resistance, high voltage, and high frequency. Military and other specifications may also influence the choice of resistor.

Conclusion
Choosing the right resistor involves considering various factors to ensure it meets the application's requirements. Standard resistors should be considered first, and if unavailable, non-standard options can be explored.

Resistor Selection and Environmental Factors
Resistors and other electrical components have limitations on the maximum temperature they can reliably operate at. The service temperature is the sum of ambient temperature and the temperature rise due to heat dissipation. Various factors affect the temperature rise, including ambient temperature, enclosure, grouping, and altitude.

Ambient Temperature Derating
Power resistors can dissipate different percentages of full load depending on ambient temperatures. High ambient temperatures require derating.

Derating Due to Enclosure
Enclosure affects derating based on factors like size, shape, material, and ventilation. Fig. 5 illustrates temperature variations with enclosure size for a power resistor.

Derating Due to Grouping
Nearby heat-producing units affect temperature rise. Fig. 6 shows power ratings for resistor groups with various spacings.

Derating for Altitude
Fig. 7 shows power ratings at different altitudes under standard atmospheric conditions.

Pulse Operation
Pulse operation may allow higher power in pulses than continuous duty. NEMA duty cycles and resistor ratings are shown in Fig. 8. Curves in Figs. 10-13 illustrate on and off time combinations for various loads.

Cooling and Limited Temperature Rise
Forced air cooling allows operation at higher wattage. Fig. 14 shows a typical curve for forced air cooling. Operating at less than maximum temperature rise is possible by referring to Fig. 2.

Temperature Coefficient of Resistance (TCR)
Resistance alloys show minimal change with temperature, but TCR can cause changes of -4% to +8% at full load. TCR is expressed in ppm/°C. Special applications may require specifying maximum permissible TCR.

Short-Cut Chart Method
This method helps determine the required resistor size based on application conditions. Factors like ambient temperature, enclosure, grouping, altitude, pulse operation, cooling air, and limited temperature rise are considered.

1. Temperature Coefficient of Resistance (TCR):
The TCR of a power resistor can vary due to factors like heat treatment and construction materials. The TCR range for certain wires on vitreous enameled resistors can increase significantly from the original specification. Designers should consider the actual circuit needs and select resistors that operate at low temperature rises for maximum stability. Ohmite offers resistors with "Ohmicone" coating for better TCR control.

2. Resistance Alloys and Uses:
Various resistance alloys are used in winding resistors and rheostats, each suitable for different resistance ranges. The document provides a table of alloys with their compositions, resistance per circular-mil-foot (CMF), and temperature coefficients. Alloys like Nickel and "Hytemco" are used for ballast resistors due to their high TCR.

3. Ohm’s Law:
Ohm’s Law defines the relationships between power (P), voltage (V), current (I), and resistance (R). The document provides formulas for calculating these parameters, emphasizing the importance of understanding these relationships in circuit design.

4. Preferred Standard Resistance Values:
The document lists standard resistance values designated by the International Electrotechnical Commission (IEC), ensuring representation of every possible resistance value within its tolerance range.

5. Resistor Terminology:
Definitions of various terms related to resistors are provided, such as adjustable resistor, ambient temperature, armature resistor, and dielectric strength. These definitions help in understanding the specifications and applications of different resistor types.