When using, it shall be made sure that the overload conditions at unusual moments lie within the fusing territory. Consult with us in advance when overloaded higher than the rated voltage under an ordinary situation since such an overload may store up damages on resistors.
Use at the maximum open- circuit voltage or lower as an arc phenomenon may arise when high voltage is applied again after fusing by an over current. Consult with us for the maximum open- circuit voltage because it varies with type and resistance.
Download complete PDF file - Resistor Precautions in Usage.
When being used in AC circuits, some wirewound structures give inductance ingredients or parasitic capacity, so they may cause unusual phenomena such as oscillations etc. Quorum deviations of other components should be carefully taken into account for use.
Application and Placement: Wire wound resistors use different gauges of wire as resistance elements. Sometimes the gauge is extremely thin (finer than a strand of human hair) and very susceptible to breakage in environments containing salts, ash, dust and corrosives. Avoid utilization in such environments.
Do not install in dusty areas because the accumulation will cause shorts and poor conductance.
Care should be taken to the fact that slipping out of position during mounting may increase to cause solder bridges. As chip networks receive mechanical stress easier than chip resistors, take care so that no strong mechanical stress is given during and after the mounting. An incorrect solder volume increases stress on resistors and may result in cracks or performance defects. Be careful to avoid too much or too little soldered volume.
Precautions in Use
The types and the specifications in this catalog are typical ones.
Before use, please make sure of specifications and precautions in use with the contents of specifications for supply or ask our sales offices for the specifications.
When components are used for special applications requiring high reliability (life maintenance equipment, atomic energy, airplanes, artificial satellites, etc.), contact us beforehand. Also make sure to evaluate and verify the components in a state that they are mounted on actual equipment.
Soldering shall be performed within the specified temperature, time and number of times for each component. If the components are heated to high temperature for a long time, the colors and characteristics may change, and disconnection may occur.
After soldering, keep the component from stress until it is cooled down. After soldering, be sure not to give any mechanical stress on the terminal section by warping of the printed board, etc.
If the components are used in circuits where pulse wave current (single pulse, repeated pulse) or surge current flows, consult us beforehand. Also note that it is necessary to check with actual circuits considering dispersion of the tolerance values of the other components.
The components should be kept away from high temperature, high humidity, direct sunlight, heat, corrosive gas (brimstone, chlorine, acid, alkali, etc.). Please inquire us about the storage term of products.
Be careful not to leave ionic substances contained in solder flux after washing the flux. Especially when non-washing- soldering, water washing or water- soluble detergent is used, it is essential to confirm reliability of the components before use.
For basic particulars for cautions, refer to EIAJ Technical Report RCR-1001 "Safety application guide for electronic parts".
Warping of printed boards, which is caused by heat, gives stress directly to components when boards are cooled down.