Summary:What are the precautions for the installation of aluminum electrolytic capacitor...
What are the precautions for the installation of aluminum electrolytic capacitors
(1) Do not use the capacitors that have been energized and assembled to the equipment. Except for capacitors that are dismantled to check electrical performance during periodic maintenance, they cannot be reused.
(2) Even after the capacitor is discharged, a voltage (re-flash voltage) may still be generated between the terminals. At this time, please discharge through a 1kΩ resistor.
(3) The leakage current of capacitors stored for more than half a year may increase. In this case, perform voltage processing through a 1kΩ resistor.
(4) Install the capacitor after confirming the rating (capacitance and voltage).
(5) Install the capacitor after confirming the polarity of the capacitor.
(6) Do not drop the capacitor to the ground, and do not use the dropped capacitor.
(7) Do not deform the capacitor body during installation.
(8) Make sure that the capacitor terminal spacing and the printed circuit board hole spacing are consistent before mounting.
(9) When mounting the self-supporting capacitor on the substrate, it should be pushed in to the extent that it is in close contact with the substrate (non-floating state).
(10) Use the automatic insertion machine to kink and fix the strength of the capacitor leads not too much.
(11) Please pay attention to the impact force caused by the adsorber, product inspector and centering operation of the automatic insertion machine and assembly machine.
(12) Soldering with a soldering iron
① Welding conditions (temperature, time) must not exceed the range specified in the delivery approval.
②When the lead terminals need to be processed due to the inconsistency between the terminal spacing and the printed circuit board hole spacing, the capacitor body must not be subjected to pressure during processing before soldering.
③When trimming with a soldering iron, if you need to remove the soldered capacitor first, please melt the solder before removing it, so as not to put pressure on the terminals of the capacitor.
④Do not let the tip of the soldering iron touch the body of the capacitor.
(13) Flow welding
①When soldering, do not immerse the capacitor body in the solder. Insert the printed circuit board and solder only the opposite side of the capacitor side to the back.
② Soldering conditions (preheating, soldering temperature, terminal dipping time) must not exceed the range specified in the delivery approval.
③ Except for the terminal part, do not adhere to the flux.
④When welding, be careful not to overturn other parts and touch the capacitor.
(14) Reflow soldering
①Welding conditions (preheating, welding temperature, time) shall not exceed the range specified in the delivery approval.
②When using an infrared heater, since the infrared absorption rate varies depending on the color and material of the capacitor, it is necessary to pay attention to the degree of heating.
③ Please set the number of times of reflow of the capacitor to 1 time. However, if it is necessary to set 2 reflows, please consult us.
(15) Among the halogen-free fluxes, some of them do not contain ionic halogen compounds, but contain a large amount of non-ionic halides. When such compounds enter the capacitor, they will chemically react with the electrolyte, which may cause a chemical reaction with the electrolyte. Same ill effects after cleaning results. Please use flux that does not contain non-ionic halogen compounds.
(16) When the capacitor is left in an environment of 150°C for more than 2 minutes due to the preheating of surface mount components and the hardening of the resin used to fix the capacitor, or the high temperature gas or hot wire directly contacts the capacitor, the outer box may be damaged. Shrinkage, expansion, rupture occurs.
(17) After the capacitor is soldered to the printed circuit board, the capacitor body must not be tilted, laid down or twisted.
(18) After soldering the capacitor to the printed circuit board, do not use the capacitor as a handle to move the printed circuit board.
(19) After soldering the capacitor to the printed circuit board, do not allow other objects to collide with the capacitor. Also, when placing printed circuit boards on top of each other, do not touch the capacitors with printed circuit boards or other components.
(20) Cleaning Cleaning method Objects: All varieties, all specifications Ethanol-based cleaning agents
Isopropyl alcohol Aqueous cleaner Advanced ethanol
Cleaning conditions: Use soaking, ultrasonic and other methods. After cleaning, the total cleaning time should not exceed 5 minutes (the temperature of the cleaning solution is below 60 ℃). After cleaning, please dry the capacitor and the installed printed circuit board with hot air for more than 10 minutes at the same time. The temperature of the hot air should be controlled below the upper limit of the classification temperature. In addition, if the drying is insufficient after washing, it may cause poor appearance such as secondary shrinkage of the jacket and swelling of the soleplate. Attention is required. Please do a good job in the pollution management of cleaning agents (conductivity, pH value, specific gravity, water content, etc.). After cleaning, do not store it in the environment of cleaning solution or in an airtight container. Depending on the cleaning method, sometimes the product label disappears or the label is blurred.
(21) Fixing agent, coating agent
①Do not use fixatives or coating agents containing halogen-based solvents, etc.
②Before using the fixing agent and coating agent, please clean the space between the substrate and the sealing part of the capacitor, and do not leave flux residue and dirt.
③Before using the fixing agent and coating agent, please dry the cleaning agent, etc.
④ When using a fixing agent or a coating agent, do not block the entire surface of the capacitor sealing part. There are many types of fixatives and coating agents, so please contact us for details.
(22) With regard to fumigation, as a pest control measure at the time of export, fumigation with halogen compounds is sometimes required. When aluminum electrolytic capacitors and machines equipped with aluminum electrolytic capacitors are directly fumigated or fumigated wood is used for brackets, the fumigant contains halogen, which may cause a corrosion reaction inside the capacitor.