Soldering is the process of joining two or more components by melting and filling a metal (solder) into the joint. A soldering station is a multipurpose power device designed to solder electronic components such as PCBs. The station houses several soldering tools connected to the main unit, such as the controls (temperature and voltage controls) and means of indication. It may also be equipped with an electric transformer. Modern solder stations also include solder iron holders, stands, soldering tip cleaners, etc.
Solder iron is the most critical component in a soldering station, fusing the metal and joining two or more electronic components. The soldering iron has a metallic tip at one end and a thermal/electrically insulated handle attached. Electric current is passed onto the soldering iron, and due to electrical resistance, the metallic tip is heated, which in turn melts the metal and fuses the components. Solder Pencil and Solder Gun are the two solder irons widely used in the industry. Soldering pencil is used for low-duty applications such as household appliances and is compact in design. Soldering guns draw amperes of current and are used for enterprises and other heavy-duty applications.
Soldering stations are commonly used across industries, workshops, electronics repairing, and electronic laboratories. Depending on the functional characteristics and application, soldering stations are classified into five types:
Depending on the application requirement, solder stations are integrated with temperature and voltage control systems to heat the fuse metal optimally. Constant-voltage soldering stations are temperature-limited but do not incorporate a temperature sensor. They depend on the increasing thermal resistance of the heating element to limit tip temperature. Due to the constant voltage power supply, line voltage fluctuations and ambient temperatures significantly affect the temperature of the soldering tip and affect the fusing job and so require highly skilled operators to perform the task. However, constant voltage stations are commonly used as they are the least expensive amongst all soldering irons.
Variable-temperature soldering irons incorporate a temperature-control device in the soldering handle. A control knob on the power source controls the voltage passed through the soldering iron, varying the tip temperature. When the soldering tip achieves the prescribed temperature, the current to the heater is turned off. The tip cools to the lower temperature setpoint of the controller, and the current to the heater is turned back on. Tip temperature calibration is possible with variable-temperature soldering irons. This type of iron can be adjusted so that its temperature is balanced with the thermal requirements of the joint.
When selecting a soldering iron, potential damage to the PCB and its components must be considered. Damage can result from excessive joint temperatures or electrical overstress. Thermal damage can result from an iron that is not temperature controlled or is operated at too high a temperature. In contrast, electrical overstress results from the flow of electrical energy (leakage or electrostatic) when the iron is placed in contact with the component, which damages or weakens an electrical part. Therefore, in addition to the application (contact or non-contact type soldering), three factors are critical for the selection of a soldering station:
Soldering Testers are designed to test and examine hand-held soldering irons used in the assembly of electronic components. These testers are often used as a quality tool to assist manufacturers in complying with Soldering Standards IPC/EIA J-STD-001C. Solder testers validate the performance of solder stations by measuring the Temperature, AC voltage, AC and DC voltage, and Resistance to Ground values. Modern testers can detect voltage spikes on the soldering iron tip, which hampers the soldering process.
Appendix A of the IPC-J-STD-001 details the calibration standards of soldering stations/irons. The critical parameter to be tested on a solder station is the temperature response of solder housing for the current supply at various loads. According to the guidelines, these loads should not impact the physical temperature more than +10 degrees C, and the validation procedure is mentioned below:
In addition to the points mentioned above, tip-to-ground potential and tip-to-ground resistance should be within the OEM-defined operating limits. The following points describe why is calibration essential for Solder stations and testers:
Cumulative errors often result in operational uncertainties, affecting the accuracy of the soldering process. Calibration avoids these errors, ensures the soldering station and testing kit accuracy for sustained and repeated use, and enhances service life. Following a regular and timely calibration schedule ensures accuracy of measurement and improves process accuracy.
e2b calibration offers industry-leading ISO-certified solder station and tester calibration services. Our labs are ISO/IEC 17025 accredited and operated by a team of qualified calibration experts to test and calibrate your soldering kits. Our verifiable services are unmatched in the industry. We are registered with ANAB. We are also ANSI/NCSL Z540-1-1994 certified. We have the NIST Traceable Wide scope of ISO/IEC 17025 accreditation. Contact e2b calibration for all your equipment calibration needs.