What are the installation methods for electrolytic capacitors?

The installation method of electrolytic capacitors needs to be flexibly selected according to the space, heat dissipation requirements, and stability requirements of the circuit board, mainly divided into three categories: vertical, horizontal, and special scenario installation. The following are specific installation methods and operating points:
1、 Basic installation method

Vertical installation

Operation steps:
Insert the capacitor pins vertically into the holes on the circuit board, ensuring that the body is parallel to the board surface;
When the pin spacing does not match the board hole spacing, the pins can be slightly separated for adjustment (to avoid root bending);
Insert to the bottom to enhance stability and reduce the impact of distributed capacitance on high-frequency circuits.
Applicable scenarios: General circuits with ample space, such as power filtering modules.
matters needing attention:
The polarity must be correct (the horizontal bar/ribbon end of the shell is negative);
Large capacity capacitors (diameter ≥ 14mm) are prohibited from being fixed with pin load-bearing.

Horizontal installation

Operation steps:
Bend the pins in the same direction (≥ 3mm from the root) and insert them horizontally into the board hole;
After welding, apply silicone gel to the bottom for fixation to prevent vibration and detachment.
Applicable scenarios: Highly restricted compact devices (such as car audio systems, portable devices).
Risk statement
Excessive bending can easily lead to internal lead breakage;
Silicone may age and fail in high-temperature environments, and high-temperature resistant models should be selected.
2、 Special installation scenarios

Adjustable installation (rotating seat structure)

Design principle: By coordinating the rotating seat with the fixed half ring, the capacitor can switch between horizontal and vertical states.
Operation points:
After inserting the pin into the positioning slot, lock and fix the half ring;
The rotating seat should be flush with the lower surface of the base to ensure stability.
Advantage: Adapt to multi-directional spatial constraints (such as modular design of industrial equipment).

Installation of onboard capacitors

Core requirements:
Install close to the battery to shorten the current path;
Avoid high temperature areas (engine compartment), humid areas, and vibration sources.
Fixed method:
Secure the bracket screws with shock-absorbing washers;
Supercapacitors require additional consideration of heat dissipation space.
3、 Key processes and risk management
Common errors and consequences of standardized operation procedures
Visual inspection of the "-" mark/color band on the shell for polarity confirmation (black/gold is negative); Multimeter verification (when the reverse resistance value is high, the red meter pen end is negative) reverse connection → significant increase in leakage current, bulging explosion (tantalum capacitor has the highest risk)
Welding process - manual welding: temperature ≤ 350 ℃/time ≤ 3 seconds, soldering iron should avoid the capacitor body;
-Wave soldering: The capacitor is not immersed in tin solution, and the solder only covers the terminal, causing the electrolyte to dry up due to overheating; Mechanical stress strain on internal leads
Post installation processing - remove excess pins to prevent short circuits;
-Do not twist/tilt the welded capacitor;
-Avoid contact with external forces during storage to prevent damage to the seal due to stacking pressure → leakage failure
Selection and installation suggestions
Space priority: For compact scenes, choose horizontal and silicone fixed, vertical for better heat dissipation;
Vehicle/industrial scenarios: Priority should be given to high-temperature resistant models (above 105 ℃), and supercapacitors need to be reinforced with mechanical fixation;
Repair operation: Fully melt the solder during disassembly to avoid forcefully pulling the pins.
Attachment: Quick Check Table for Installation Process
Graph TB A [polarity confirmation] -->B [choose installation method] B -->C {vertical? }C -->| Yes | D [Insert vertically to the bottom] C -->| No | E [Pin bending+horizontal insertion] D&E -->F [Welding temperature ≤ 350 ℃/3s] F -->G [Pin cutting+Glue fixation] G -->H [Functional testing]
Proper installation can significantly extend the lifespan of electrolytic capacitors, especially in preventing polarity errors and mechanical stress damage. The fixed state should be checked regularly in high temperature and high humidity environments.