Questions tagged [flux]
Refers to flux chemicals used in soldering. Use the magnetic-flux tag when referring to magnetic field changes.
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Why does speed of DC motor increase when flux is reduced?
I understand that from KVL
e = v -IaRa e=k(flux)speed
speed=(constant)*(V-IaRa)/flux
But physically what causes the speed to increase? What force causes the rotor to accelerate? In fact, ...
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Should I spray some flux on my board before putting it in the reflow oven?
I am using Tin-Lead solderpaste to make my prototype circuits. This is the exact solder paste:
ALPHA OM-5100 (https://alphaassembly.com/Products/Solder-Paste/OM-5100)
...
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Effects of no-clean flux or RMA flux residue on signals
I keep on hearing that no-clean solder paste or flux is bad for analog or digital signals because it makes analog signals "noisy" and promotes cross talk on digital signals.
Like this claim:...
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soldering a 12V plug cathode
I cant seem to properly solder a stranded wire to that cathode terminal. Checked the answer https://electronics.stackexchange.com/a/90605/35737 - fluxing it did not help and solder does not adhere to ...
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What type of electronics soldering is this soldering flux used for?
I usually use rosin flux for soldering or one with rosin core if the solder refuses to stick. I recently found this Goot BS-15 flux, but it says not applicable to PC boards. The label says hobby use ...
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Residual flux conductivity on PCBs causing problems?
The question here is how much flux remains on boards under normal manufacturing conditions, how conductive is it, and does the conductivity change with humidity and temperature.
I know that for ...
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What is the internal linkage flux of a wire with radius a(shaped like a cylinder)
How can we clarify that the relation between linkage flux an flux in a cylinder shaped wire is \$ d\lambda=\frac{x^2}{a^2}\ d\phi \$?can we illustrate this by electromagnetic formula?I think I would ...
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Mosfet failure in DC-DC switching converter: root cause analysis and countermeasures
I'm dealing with a pilot project which involves several units on the field (around 15 units) powered by a control card which needs to drive two resistive loads in DC in the range of 13-5 VDC. Each of ...
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Soldering question
Yesterday I soldered quite some things, but I'm still a beginner.
I noticed that sometimes it happened that sometimes I use to much solder. When trying to remove it, I heat the pin with solder so it ...
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Bismuth or Indium solder - how do they compare?
In my previous question I focused on lead-based solder alloys (see Best solder wire - Sn63Pb37 vs Sn60Pb40 vs ...?).
Some of you brought new exciting solder alloys to my attention. The two most ...
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Is acetone or isopropyl alcohol better for removing rosin flux?
For removing rosin flux from my board, should I use Acetone or Isopropyl Alcohol? I need an easily available solvent.
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Best Solder & flux for jewellery made with copper foil? [closed]
I want to make some glass jewellery with copper foil, but obviously can't use my usual lead solder that i use for my stained glass art, which is the best lead-free solder and what flux would it need. ...
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I need help for soldering. Is this good flux for use on PCB/Electronics?
this is a specific question to a product for soldering.
I am a newbie to soldering so be kind.
To be honest I was trying to learn soldering and watched videos and read some.
But in germany there ...
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Solder Paste vs Solder Flux
I bought a "Solder Paste". It is in quote because I'm not really sure if it's a Solder Paste itself.
I researched about what Solder Paste is and, by definition, is defined as a mixture of small ...
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Stainless steel soldering
Was wandering whether anyone could suggest how to solder stainless steel. I know hydrochloric acid flux is suggested to remove oxidation. Anyone could suggest a supplier in UK or who would be able to ...
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Hakko FX-888D Iron Issue
I just got a new Hakko 888D for Christmas. I have used it a bit since then, and I'm using the wet sponge, brass sponge, and some RadioShack tip cleaner to maintain the tip quality. The issue I am ...
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When do I choose to use a rosin based flux or rosin-free flux?
What are the general guidelines for determining when flux should or should not have rosin?
Thanks
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Will my wires have current stability issues?
first post here.
I'm currently making a set custom sleeved/crimped cables for my computer's modular power supply, and my crimper isn't very good, so for extra security, I've soldered all the crimps, ...
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Which flux type to use for SMD hobbyist (home-made) PCB?
"Short" question
Which flux type to use for SMD hobbyist (home-made) PCB?
How to know if a specific flux (e.g. F-SW-33) is no-clean or require cleaning.
How to know if a specific flux conduct ...
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Why does the electronics industry use the adjective "organic" when it adds no information?
This has been nagging me for a while. I'm an engineer, not a chemist, so I've probably misunderstood something.
The electronics industry uses the adjective "organic" a lot when describing materials. ...
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One flux for all electric soldering?
My understanding is that standard electrical soldering fluxes will not be effective on aluminum or stainless steels. Is that correct?
But are all rosin fluxes adequate for the other metals ...
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Wireless Power Coil - Is this shielding? Field shaping?
I'm taking apart a Qi wireless power transfer receiver. The coil is etched into the pcb. The entire coil area (approximately 3.75 x 4.5 cm) is covered by a rectangular piece of hard, brittle material.
...
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Induced voltages and flux within a transformer and their polarities
This is a multifaceted question, and is more to see if I understand what happens inside a transformer. I understand the general idea behind transformers: Alternating voltage that is applied to the ...
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Hand soldering QFP component
I recently came across this video on YouTube, in which the guy is soldering a .5 mm QFP component.
Hand soldering a .5 mm QFP Chip
As I haven't done a lot of soldering in my life (and never used ...
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What is the difference between flux and flux-linkage? how to calculate inductance of transmission lines?
in calculating inductance of a single current carrying conductor how flux linkage is calculated?why flux is multiplied by a factor (X^2)/(r^2) to get flux linkage.
see the following images:
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What are those black spots in these lead-free solder joints?
I have just changed to lead-free solder (I'm now using Chip Quik's "SMDSWLF.031, a Sn96.5/ Ag3.0/ Cu0.5 solder with 2.2% no-clean flux) but I'm not sure what I'm seeing when inspecting my boards.
The ...
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How long can you leave flux on a PCB?
How long can flux be left on a PCB?
I am working on one of my PCBs and I have put flux on it to solder. Can I leave it overnight. Is that ok? Or how long can flux be on the board?
update: 715 water ...
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Components to avoid using on an ultrasonic cleaner
What components populated on a PCB are not safe to clean in an ultrasonic cleaner?
It is not limited, but I specifically wonder below components if they are safe to use or some requires special ...
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Can liquid soldering flux be refrigerated?
I've been upgrading my soldering mojo lately and have collected an assortment of liquid fluxes.
The Kester 951 and Kester 186 datasheets state shelf lives (1 and 2 years respectively) when stored ...
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in order to understand bldc motors and their working principle, I read a lot on the web, and I see them like a tripolar steppers, am I right?
I was told my previous questions were not well received by the community, it was never my intent to post a repeated question or a bad formulated one, and english is my second language, not my maternal ...
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What does "no clean" solder actually mean?
I bought some solder that says it doesn't require cleaning. The description specifically says "Eliminates the need and expense of cleaning". But there's still a lot of some substance left on my board ...
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Chipquick SMD291 No-clean Paste Flux - Conductive?
I'm using this brand and type paste flux, and it works very well... except for one small problem. After assembling 5 prototypes, most had bizarre issues, which were resolved when the flux was removed ...
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Mitigate the effects of magnetic induction heating in a three phase AC system
To mitigate the effects of magnetic induction heating in a three phase AC system, it is common practice to group the conductors and to keep them in the same raceway. Also, three phase power is ...
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Does a 1 watt 660nm LED put out more radiant flux than a 1 watt 630nm LED?
Given two LED chips consuming same or very similar amounts of DC power,
One emitting light peaking at 630nm,
The other at 660nm,
In terms of output of (but light irrelevant to the sensitivity of ...
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How to clean "no clean" flux with a 3L ultrasonic cleaner
I am doing some small batches of PCBs, like 100 each time, using solder wire with no clean flux core.
I am using this solder wire. The datasheet recommends IPA and water at 60º.
Usually, I clean it ...
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How do I pick a flux cleaner that's safe for use without industrial ventilation?
I was looking at getting this flux cleaner: Fluxclene FLU200D but then I noticed that in the datasheet, it mentions an inhalation toxicity of 300 ppm. That sounds like it's easily exceeded by just ...
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Solder sticks to PCB (not just the pads!)
I'm having a severe problem with solder adhering to the FR4 PCB material. I made my boards (myself, my first time) using positive developer and etchant on a pre-sensitized board. I washed the etchant ...
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How does flux exist in a transformer?
What I understand about working principles of ideal transformer:
We apply an alternating voltage at the primary side. This creates a flux inside the transformer core (\$\Phi_p\$). Some voltage is ...
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Polarity of the induced voltage on inductor for an applied magnetic flux according to the Lenz's Law
I'm trying to visualize the Lenz's Law on a practical inductor.
The Lenz's Law says that
$$ \mathcal{E} = -\dfrac{\partial \Phi}{\partial t} . $$
Now, assume that there is a magnetic flux inside ...
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Where does the flux go when desoldering?
I have a piece of equipment with a right angle miniUSB port that went bad. After pulling the old port I have a big blob of solder shorting out the traces.
So obviously I must get rid of the blob ...
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Accidentally used plumbing flux on a PCB; How do I remove it to reuse the board?
Two weeks ago, I picked the wrong tub of flux from my toolbox and used it for making a 9VAC -> 5VDC adapter. I fluxed all the components and soldered it down before realising I was using PLUMBING flux!...
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How does flux work, chemically, and what are the products?
Ususally, electronics solder comes with a built-in flux core. Among the solders I have laying around, I have a silver/tin solder with an "F-SW-21" flux core (ISO 9454-1: 3.1.1, this is zinc chloride ...
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Removing rosin flux residue from PCB
I have a nice looking purple PCB from Laen's batch service, which I have assembled using rosin flux. I have cleaned the board as best I can with isopropyl alcohol, which gets rid of the tackiness of ...
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How to calculate flux density in a toroidal CT that has an electrical line pass through the center?
I have seen the Biot-Savart equation but I don't know how to apply it. Also does the conductor length need to be considered finite and equal to the core length or will the calculation be for infinite ...
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Magnetic path length and permeability relation
In a transformer, does increasing the magnetic path length reduce flux and permeability and increase thr reluctance of the core?
If yes, why does the equation of relative permeability of a gapped core ...
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How can I solder to stainless-steel semi-rigid coaxial cable?
I need to run coaxial cables into a cryostat, and because copper conducts too much heat, I decided to use semi-rigid stainless steel cables. As far as I can tell, both the shield and the inner ...
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Can I use Formula SP-30 self-cleaning acid paste flux?
I am a complete noob when it comes to soldering. I've only done a little bit in the past and it was years ago. Today, I bit the bullet after reading about how to solder and purchased some soldering ...
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F-SW22 vs F-SW33 flux. What to these figures mean?
I was thinking of purchasing a no-clean flux pen from my supplier, but there are two options, F-SW22 and F-SW33. What do these codes mean and what types of job is each suitable for?
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Why voltage lags by 90° from magnetic flux?
I was not sure if I should write it here or on Physics board, but I will give a try.
As I understood current (generally emf) can be generated in a system by varying magnetic flux.
For example, let's ...
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What Can Be The Cause Of Low Voltage After Resoldering?
I had to resolder mosquito zapper's black and red wires back after zapper fell on the floor and black wire detached and later red wire detached when i was trying to solder black wire back. After ...
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