Reference

Glossary

Short, plain-English definitions. Each term links to the guides that cover it properly.

A

Acid-core solder: Solder with a corrosive acid flux in its core, made for metalwork rather than electronics. Canfield, a solder maker, says it is not recommended for electrical or electronic soldering because its residue is corrosive. Read more: How to choose solder for electronics
Activated carbon filter · also carbon filter: A filter that captures gases and odors rather than particles. EPA says activated carbon can be effective provided a large amount of material is used, and that gas-removing portable air cleaners have no widely used performance ratings. Read more: Solder smoke absorber vs fume extractor
Airflow rating (hot air): How much air a hot-air station blows. Makers state it differently: YIHUA gives up to 120 liters per minute for its 959D, while QUICK's 861DW uses a 1-120 step scale, so the two numbers cannot be compared. Read more: Hot-air rework station buying guide
ANSI/ESD S20.20 · also S20.20: The ESD Association's standard for running an ESD control program, which ESDA calls the cornerstone of effective ESD control. It requires all conductors, including people, to be bonded to a known ground, and it was updated in 2021. Read more: How to set up an ESD-safe bench

B

Barlow lens: An auxiliary lens fitted under a stereo microscope's objective to change magnification and working distance. AmScope says its 0.5X Barlow halves magnification and doubles both working distance and field of view. Read more: Microscope magnification explained
Bench power supply · also bench PSU, lab power supply: An adjustable DC supply with a voltage setting and a current limit, used to power a board under control while you diagnose it. Useful extras include over-voltage and over-current protection; Rigol's DP700 models, for example, switch the output off when either trips. Read more: How to use a bench power supply
Bevel tip · also angled tip: A round tip cut off at an angle, leaving an oval flat face. The face carries a small pool of solder and gives good contact on pads and pins; JBC lists bevel shapes among its C210 cartridges. Read more: Soldering tip shapes

C

C115 · also NT115, nano cartridge: JBC's smallest cartridge range, for the NT115 nano iron and the AN115 and NP115 nano tweezers, meant for very small components under a microscope. JBC's CDN station lists 25 W peak with it, and C115 replaces JBC's C105 range; see C115 tips. Read more: C115 vs C210
C210 · also T210, C210 cartridge: JBC's precision cartridge range for the T210, B.100 and B.500 handles. JBC rates the T210 at 40 W peak for accurate work with medium power, such as small SMD parts under magnification; see C210 tips. Read more: C210 vs C245, C115 vs C210
C245 · also T245, C245 cartridge: JBC's general-purpose cartridge range for its T245 handle, which JBC rates at 150 W peak and describes as suited to SMD work and high-power jobs such as ground planes. Third-party "C245" tips and handles share the format, but JBC's figures do not apply to them; see C245 tips. Read more: C210 vs C245, T12 vs C245 soldering tips
Cartridge tip · also cartridge, heater-in-tip: A replaceable tip with the heater and temperature sensor built in. Hakko describes its T12 tips this way and credits the design with greatly improved thermal recovery; JBC also sells its C245, C210 and C115 tips as cartridges. Read more: T12 vs C245 soldering tips, T12 vs T15 tips
CAT rating · also measurement category, CAT II, CAT III: The measurement category a meter is built for. Fluke summarizes CAT I as protected electronic equipment, CAT II as plug-in loads such as appliances and portable tools, CAT III as fixed distribution equipment, and CAT IV as the utility connection; a higher CAT means more available energy and higher transients. Read more: Multimeter CAT ratings explained
CE marking · also CE: The manufacturer's declaration that a product meets EU legal requirements. The European Commission says CE does not mean the product was approved as safe by the EU or any other authority, and it does not show where the product was made. Read more: UL, ETL, CE and FCC marks explained
Chisel tip · also screwdriver tip, flat tip: A tip ground to a flat, screwdriver-like blade. Its flat face touches more of the joint than a point, so it moves heat in faster; Adafruit says it works well for through-hole parts. A medium chisel makes a good first tip. Read more: Soldering tip shapes
Cold joint · also cold solder joint: A joint where the solder did not melt completely, leaving a weak or unreliable connection. Adafruit says it can usually be fixed by reheating the joint until the solder flows. Read more: How to choose solder for electronics, Why solder won't stick to the tip
Common point ground: The single connection where an ESD workstation's mat and wrist strap are tied to ground. ESDA says the preferred connection is to the equipment grounding conductor, the third wire of the outlet; follow the mat maker's instructions rather than improvising a connection. Read more: How to set up an ESD-safe bench
Conical tip · also pointed tip, needle tip: A tip that tapers to a round point. It reaches between crowded parts but touches the joint over a very small area, so it is slow to heat anything larger; Adafruit says a fine point suits very small surface-mount parts. Read more: Soldering tip shapes
Continuity test: A multimeter mode that beeps when the probes find a low-resistance path, used to trace connections and find broken tracks or shorts without watching the display. Test only with the circuit unpowered.
Current limit · also constant-current mode, CC mode: The maximum current a bench supply will deliver. Tektronix explains that if a load tries to draw more, the supply clamps the output at that limit and switches to constant-current mode, which is why a low limit helps protect a board with a short. Read more: How to use a bench power supply

D

Desoldering gun · also desoldering tool: A powered tool with a heated nozzle and a built-in vacuum pump that melts a through-hole joint and sucks the solder away in one step. Hakko's FR-301 is an example, with interchangeable N61 nozzles and sensor-controlled temperature. Read more: How to use solder wick
Desoldering pump · also solder sucker, solder vacuum: A spring-loaded hand pump that sucks up molten solder when you release its plunger next to a heated joint. SparkFun calls a solder vacuum a great tool for clearing solder left in through-holes. Read more: How to use solder wick
Digital microscope · also HDMI microscope, screen microscope: A camera with a magnifying lens that shows the image on a screen. Its X figure depends on screen size (Andonstar quotes up to 300X for its AD409 on a 27-inch monitor), and some EEVblog forum users find display lag and the flat image harder to solder under. Read more: Digital vs stereo microscope for soldering, Hayve 7-inch digital microscope: research notes
Diode mode: A multimeter mode that passes a small current through a part and shows the voltage across it, used to check diodes and transistor junctions and to compare a suspect board against a known-good one.

E

ESD (electrostatic discharge) · also static discharge: The rapid, spontaneous transfer of static charge between objects, as when a spark jumps from your finger. ESDA says it can destroy parts outright or leave hidden damage, and that many components are susceptible to discharges below 100 V. Read more: How to set up an ESD-safe bench
ESD mat · also static-dissipative mat, ESD worksurface: A static-dissipative work surface connected to ground so charge drains away slowly. ESDA puts ESD worksurfaces at 1 million to 1 billion ohms to ground; a heat-resistant silicone repair mat is not automatically an ESD mat. Read more: How to set up an ESD-safe bench
ESD-safe: A claim that a tool will not build up or pass on static that can damage parts. Look for a stated standard or published figures rather than a logo: JBC says its T210 handle meets ANSI/ESD S20.20, and Hakko sells a grounded three-prong version of its FR-301 desoldering tool to prevent electrostatic damage. Read more: How to set up an ESD-safe bench
ETL Listed Mark · also ETL: Intertek's certification mark. Intertek says it shows a product was independently tested and certified to applicable safety standards by Intertek, an NRTL, and you can check a listing in Intertek's Directory of Listed Products instead of trusting a logo in photos. Read more: UL, ETL, CE and FCC marks explained
Eutectic: An alloy that melts and freezes at a single temperature instead of passing through a slushy range. 63/37 tin-lead is eutectic: Kester lists it at a single 183°C, while 60/40 melts over 183-190°C. Read more: 63/37 vs 60/40 vs SAC305 solder

F

FCC equipment authorization · also FCC ID, FCC mark: US approval for devices that emit radio-frequency energy, obtained through certification or a supplier's declaration of conformity, so they work without causing harmful interference. The program covers interference and RF exposure; it is not an electrical-safety certification. Read more: UL, ETL, CE and FCC marks explained
Field of view · also FOV: How wide an area you see at once through a microscope at a given setting; more magnification means a smaller field. AmScope lists up to 65 mm for its SM-6TZ and says a 0.5X Barlow lens doubles the field of view. Read more: Microscope magnification explained
Flux: A chemical that removes oxides from metal surfaces as you solder, so molten solder can wet them. Most electronics solder wire has flux in its core, and extra flux makes rework, desoldering and solder wick work much better. Read more: Rosin vs no-clean vs water-soluble flux
Flux-cored solder · also cored wire, rosin-core solder: Solder wire with flux inside its core, so flux is released as the wire melts. Flux content is part of the product spec: Kester's 275 no-clean wire, for example, comes with 1.1 to 3.3 percent flux cores in diameters from 0.25 to 2.5 mm. Read more: How to choose solder for electronics
Fume extractor · also fume absorber, smoke absorber: A fan unit that pulls soldering smoke away from your face and through a filter or out of the room. HSE says on-tip extraction blocks up quickly and bench-mounted boxes are of limited use unless fitted with a HEPA filter, and EPA notes that filtration does not replace ventilation. Read more: Solder smoke absorber vs fume extractor, Soldering bench add-ons

G

Ground plane: A large area of copper on a circuit board, usually tied to ground, that pulls heat away from any joint connected to it. JBC names ground-plane soldering as a high-power job for its C245 system, and SparkFun suggests a larger tip, more heat and extra flux. Read more: Why ground planes are hard to solder

H

Handle (handpiece): The part of a soldering iron you hold, which the tip or cartridge plugs into. JBC names handles with a T and the matching cartridges with a C: the T245 handle takes C245 cartridges and the T210 takes C210. Check which one a listing is selling. Read more: C210 vs C245, Soldering tip system finder
Heat-up time: How long an iron takes to reach working temperature from cold. Makers pick their own test points (Weller quotes about 28 seconds from 50 to 350°C for its WE1010NA), so compare figures only when the start and end temperatures match. Read more: Pinecil vs TS101
HEPA filter · also HEPA: A high-efficiency particulate air filter. Hakko rates the HEPA filter in its FA-430 extractor at 99.97% at 0.3 micrometers on its low and medium settings; particle filters do not remove gases, which need a gas filter such as activated carbon (EPA). Read more: Solder smoke absorber vs fume extractor
Hot-air rework · also hot-air station, rework station: Using a hot-air station's nozzle to melt every joint of a surface-mount part at once so it can be removed or fitted. Check the voltage version before you buy: some stations are sold only for 220 V, such as the YIHUA 959D on its maker's page. Read more: Hot-air rework station buying guide

I

IPC-7711/7721 · also IPC-7711/21: IPC's standard covering rework, modification and repair of electronic assemblies. IPC lists revision IPC-7711/21D among its 2024 releases.
IPC-A-610: IPC's acceptability standard for electronic assemblies, used to judge whether finished solder joints and parts are acceptable. IPC released revision IPC-A-610J on April 8, 2024.
Isopropyl alcohol (IPA): A solvent widely used to clean flux residue off boards. SparkFun suggests it for removing no-clean residue if you want a clean finish. It is flammable, so keep it away from a hot iron. Read more: How to clean flux residue

J

J-STD-001: The IPC standard that sets requirements for soldered electrical and electronic assemblies. IPC released revision J-STD-001J on April 8, 2024.
J-STD-004 (flux classification) · also IPC flux codes: The IPC standard that classifies soldering fluxes with a short code: composition (RO rosin, RE resin, OR organic, IN inorganic), activity (L, M or H) and halide content (0 for none, 1 for present). IPC lists revision J-STD-004D among its 2024 releases. Read more: Rosin vs no-clean vs water-soluble flux

K

Knife tip · also blade tip: A tip shaped like a flat blade with a long edge, handy for dragging along a row of pins or heating a long joint. JBC lists knife shapes among its C210 cartridges. Read more: Soldering tip shapes

L

Lead-free solder · also Pb-free: Solder without lead, usually tin with small amounts of silver and copper. Kester lists SAC305 at 217-220°C and tin-copper Sn99.3Cu0.7 at 227°C, and Adafruit notes that lead-free solder may need more heat and more flux than leaded. Read more: 63/37 vs 60/40 vs SAC305 solder, How to choose solder for electronics
Leaded solder · also tin-lead solder, 63/37, 60/40, Sn63Pb37: Solder made mostly of tin and lead. Kester lists 63/37 (Sn63Pb37) as melting at 183°C (361°F) and 60/40 over 183-190°C, and iFixit notes it wets well. HSE counts soldering with lead alloys as higher-risk lead work: wash your hands and face before eating or drinking. Read more: 63/37 vs 60/40 vs SAC305 solder, How to choose solder for electronics
Lifted pad: A copper pad that has come away from the circuit board, usually from too much heat, time or force during rework. Adafruit describes it as a pad detached from the board; it is far easier to avoid than to repair. Read more: How to use solder wick
Lithium-ion battery · also Li-ion, lithium polymer (LiPo): The rechargeable battery in phones, laptops, handhelds and drones. iFixit warns that a charged lithium-ion battery may catch fire if damaged, and EPA says used ones belong at battery recycling or household hazardous waste collection, never in household trash or recycling bins.

M

Microsoldering · also micro-soldering: Soldering very small parts and fine-pitch pads, usually under a microscope, as in phone board repair. JBC describes its CDN station and C115 cartridges as made for high-precision micro-soldering; see the phone microsoldering bench. Read more: C115 vs C210, Microscope magnification explained
Multimeter (DMM) · also DMM, digital multimeter: A handheld meter that measures voltage, current and resistance, usually with continuity and diode tests too. For anything connected to mains, check its CAT rating and look for an independent certification mark, which Fluke says test tools should have. Read more: Multimeter CAT ratings explained

N

No-clean flux: Flux designed to leave a small, benign residue that can stay on the board. SparkFun says cleaning is not required (isopropyl alcohol removes it if you want), and Kester describes its 275 no-clean wire as leaving an extremely clear residue. Read more: Rosin vs no-clean vs water-soluble flux, How to clean flux residue
NRTL (Nationally Recognized Testing Laboratory) · also NRTL: A private lab that OSHA recognizes to certify products against safety standards; OSHA's list includes UL, Intertek, CSA Group and TUV labs. OSHA says recognition is not an endorsement of the products, and it does not require makers to have what they sell certified. Read more: UL, ETL, CE and FCC marks explained

O

Oscilloscope bandwidth · also scope bandwidth: The frequency at which a scope shows a sine wave at 70.7% of its true size (-3 dB). Tektronix's rule of thumb is a bandwidth at least five times the highest frequency component you need to measure; Keysight suggests at least three times for analog signals and five times the clock rate for digital ones. Read more: Do you need an oscilloscope?
OVP and OCP · also over-voltage protection, over-current protection: Over-voltage and over-current protection: user-set trip points that switch a bench supply's output off if voltage or current goes past them, as on Rigol's DP700 series. Unlike a current limit, which holds the current steady, a trip turns the output off. Read more: How to use a bench power supply
Oxidation: The dull film that forms when hot metal reacts with air. Oxide on a tip or pad stops solder from wetting; Adafruit says a badly oxidized tip can usually be reconditioned with tip-tinning paste, and warns that files or abrasives damage the plating. Read more: Why solder won't stick to the tip

P

Pasty range · also plastic range: The temperature span over which a non-eutectic solder is part solid, part liquid. Kester lists 60/40 tin-lead as melting from 183 to 190°C, a 7-degree span; moving a joint before it has fully set can spoil it. Read more: 63/37 vs 60/40 vs SAC305 solder
Peak power: The most power a soldering tool can draw in short bursts, which is not the same as a station's nominal rating. JBC rates its T245 handle at 150 W peak, while its CDB station lists 175 W nominal and 130 W tool peak, so compare like with like. Read more: C210 vs C245, C115 vs C210
Preheater · also PCB preheater, bottom heater: A heater that warms a circuit board from below so the iron or hot air has less heat to supply at the joint. Hakko markets its FR-830 hot-air preheater as best suited to multi-layer boards. Read more: Do you need a PCB preheater?

R

Reflow: Heating solder or solder paste until it melts and flows into joints, then letting it cool. The word also covers re-melting an existing joint to repair it, with an iron, a hot-air station or a hot plate. Read more: Hot-air rework station buying guide
ROL0: A J-STD-004 flux code: RO for rosin, L for low activity and 0 for no detectable halides. Kester's 185 liquid flux, sold as mildly activated rosin, is classified ROL0, and so is its 275 no-clean cored wire. Read more: Rosin vs no-clean vs water-soluble flux
Rosin flux · also RMA (rosin mildly activated), colophony: Flux based on rosin from pine trees, the traditional choice for electronics. Kester says rosin residues are non-conductive and non-corrosive and normally need no removal unless the assembly runs above 200°F; HSE warns that rosin flux fume is a top cause of occupational asthma. Read more: Rosin vs no-clean vs water-soluble flux, How to clean flux residue

S

SAC305 · also Sn96.5Ag3.0Cu0.5: A common lead-free solder alloy of 96.5% tin, 3% silver and 0.5% copper. Kester lists its melting range as 217-220°C (422-428°F) and notes that the Solder Products Value Council standardized on this composition. Read more: 63/37 vs 60/40 vs SAC305 solder
Sample rate: How many measurements per second an oscilloscope takes, in samples per second. Keysight suggests a maximum sample rate of at least four to five times the scope's bandwidth. Read more: Do you need an oscilloscope?
Sleep mode · also standby, auto setback, hibernation: A feature that lowers the tip temperature when the iron rests idle, and may switch the heater off after longer idle time, to slow tip wear. Weller's WE1010NA has standby and auto setback, and JBC claims its sleep and hibernation modes extend tip life up to five times. Read more: T12 vs C245 soldering tips
SMD (surface-mount device) · also SMT, surface-mount: A component soldered directly onto pads on the board surface rather than through holes. Small SMD parts call for fine tips and magnification: Adafruit says a fine point suits very small surface-mount parts, and JBC positions its C210 system for small SMDs under magnification. Read more: C210 vs C245, Hot-air rework station buying guide
Solder bridge · also bridging: An unwanted blob of solder joining two pins or pads that should be separate. Adafruit says a bridge can usually be drawn off by dragging a hot tip between the joints; solder wick and flux also clear it. Read more: How to use solder wick
Solder fume · also flux fume, solder smoke: The smoke given off as flux heats during soldering. HSE says rosin-based solder flux fume is a top cause of occupational asthma and advises extraction at the source and keeping your head out of the plume. Read more: Solder smoke absorber vs fume extractor
Solder paste: Tiny solder particles suspended in flux, applied to pads with a stencil or syringe and then melted with hot air, a hot plate or a reflow oven. It is the usual way to assemble surface-mount boards and parts with pads underneath. Read more: Hot-air rework station buying guide, Rosin vs no-clean vs water-soluble flux
Solder wick · also desoldering braid, braid: Braided thin copper wire that soaks up molten solder when you press it onto a joint with a hot tip. SparkFun describes it this way, and iFixit notes that the braid usually comes coated with dry flux; adding fresh flux helps. Read more: How to use solder wick
Stereo microscope · also stereo zoom microscope: An optical microscope that gives each eye its own view, so you see depth while placing the iron. AmScope's SM-6TZ, for example, zooms from 3.5X to 90X with its included Barlow lenses and has a trinocular port for a camera. Read more: Digital vs stereo microscope for soldering

T

T12 and T15 tips · also T12, T15, T12-format: Hakko's cartridge tips for its FM-2027 and FM-2028 irons, sold as T12 in Japan, Asia, Oceania and other countries and as T15 in North America and Europe. Other brands make T12-format tips and stations that are not Hakko parts; see T12 tips. Read more: T12 vs T15 tips, T12 vs C245 soldering tips
T18 tips · also T18: Hakko's tips for the FX-8801 iron used on the FX-888D and FX-888DX stations, listed in about 29 shapes. The FX-888DX's optional FX-8805 iron uses T19 tips and its FX-8806 iron uses T32 tips instead; see Hakko T18 tips. Read more: Soldering tip system finder
Thermal mass: How much heat a part or copper area soaks up before it reaches soldering temperature. Big connectors, thick wires and ground planes have a lot; SparkFun's advice for ground planes and large through-holes is a larger tip, a higher temperature, extra flux and a little more time on the joint. Read more: Why ground planes are hard to solder, C210 vs C245
Thermal recovery · also heat recovery: How quickly a soldering tip gets back to its set temperature after a joint pulls heat out of it. Hakko credits its heater-in-tip T12 cartridges with greatly improved thermal recovery, which lets you work at a lower set temperature. Read more: T12 vs C245 soldering tips, T12 vs T15 tips
Through-hole · also THT, through-hole technology: Parts whose leads pass through plated holes in the board and are soldered on the far side, such as keyboard switches, header pins and most older components. Adafruit says a flat chisel tip works well for them. Read more: Soldering tip shapes, How to use solder wick
Tinning · also tin the tip: Coating a soldering tip, wire end or component lead with a thin layer of fresh solder before you make a joint. Adafruit says to keep the tip tinned with a thin, shiny layer, and SparkFun tells beginners to tin the tip before each connection. Read more: Why solder won't stick to the tip, Soldering tip shapes
Tip tinner · also tip-tinning paste, tip refresher: A paste you touch a hot tip into to clean off oxide and re-tin it. Adafruit recommends it for reviving a badly oxidized tip instead of files or abrasives, which ruin the plating. Read more: Why solder won't stick to the tip
Tip-to-ground resistance · also tip-to-ground voltage, tip leakage: The resistance, and any stray voltage, between a soldering tip and the station's ground. Low values protect static-sensitive parts; Hakko and JBC publish under 2 ohms and under 2 mV for their stations, while many marketplace listings do not state a figure. Read more: How to set up an ESD-safe bench, AliExpress soldering station buyer's checklist
True RMS · also true-RMS meter: A meter that calculates the true effective (RMS) value of an AC voltage or current, so it reads correctly on distorted waveforms as well as clean sine waves. Fluke says an average-responding meter can read up to 40% low or 10% high on distorted waves. Read more: Multimeter CAT ratings explained
TS100-style tip · also TS100 tip, TS-format: The tip format of Miniware's TS100 portable iron, also taken by the TS101 and by Pine64's Pinecil. Oscar Liang notes that TS101 tips fit the TS100 but not the TS80 or TS80P; see TS100-style tips. Read more: Pinecil vs TS101

U

USB-C PD (Power Delivery) · also USB PD, PD charger: A USB-C charging standard in which the charger and the device agree on a voltage and current. USB-C soldering irons use it to draw higher voltages: Pine64 lists 12-20 V PD input for the Pinecil V2 and recommends at least a 65 W PD charger when using its short tips. Read more: Pinecil vs TS101

V

Voltage variant · also 110 V version, 120 V version, 220 V version: The mains version of a tool. Many stations come in separate 120 V and 230 V builds under one model name, as Weller does with its WE1010 kit, and the US Department of Energy puts US outlets at 110-120 V, 60 Hz, so choose the 110-120 V variant. Read more: AliExpress soldering station buyer's checklist, Soldering stations for a 120 V home bench

W

Water-soluble flux · also organic acid (OA) flux: Flux whose residue is meant to be washed off with water after soldering. SparkFun says to remove any water-soluble flux residue left on the board, so it suits people who are ready to clean every board. Read more: Rosin vs no-clean vs water-soluble flux, How to clean flux residue
Wetting: When molten solder flows out and bonds to a clean metal surface instead of balling up on it. Flux helps by clearing oxides. iFixit notes that 63/37 leaded solder wets well, while lead-free tin-silver-copper alloys wet less readily and are harder to work with. Read more: Why solder won't stick to the tip, 63/37 vs 60/40 vs SAC305 solder
Working distance: The gap between a microscope's lens and the work in focus: the room you have for the iron and tweezers. AmScope advertises an 8-inch (200 mm) working distance for its SM-6TZ stereo microscope, which varies with the Barlow lens fitted; it says a 0.5X Barlow doubles working distance while halving magnification. Read more: Microscope magnification explained, Digital vs stereo microscope for soldering, Hayve 7-inch digital microscope: research notes
Wrist strap · also ESD wrist strap, grounding strap: A conductive band worn on the wrist and connected to ground through a resistor, most commonly 1 megohm, to keep you at ground potential while you handle parts. ESDA warns that wrist straps must not be used if you could be exposed to circuits of 250 volts or more. Read more: How to set up an ESD-safe bench