hybridfree/eevblog-posts huggingface dataset:
induction loop sensor - Page 1
Forum section: electronics / projects

author: johntg
author_rank: Newbie
timestamp: February 02, 2019, 02:48:37 am
content: Im pretty new to circuit design so any help is appreciated.I bought this induction sensor off of ebay hoping that it would have a relay built in to close a circuit to control my gate. However once received i discovered i received the solid state model that doesnt have a relay with a NO and Common connection rather an Emitter and collector connection. Ive done a bit of testing and im seeing a .2VDC change when the induction loop is triggered by metal. Im looking for help in designing a circuit that can use the emitter and collector connections and switch a Normally open relay.thank you !!http://www.renoae.com/product/root/0/82

author: Doctorandus_P
author_rank: Super Contributor
timestamp: February 02, 2019, 10:02:06 am
content: Quote from:http://www.renoae.com/RelatedFiles/Model%20L-1200%20Data%20Sheet%20%2008-05-03.pdfThe output acts as a switch. You need to apply an external voltage to it, just as with a regular switch or solid state relay.

author: soldar
author_rank: Super Contributor
timestamp: February 02, 2019, 10:51:55 am
content: Wow, that seems like overkill for detecting vehicles on your driveway.I could not find the pin-out for the connector. In any case, if it has an open collector output you can just use that directly or use it to switch a relay. A relay might not be a bad idea even if not strictly needed because it provides isolation and protection.
induction motor efficiency at reduced load - Page 1
Forum section: electronics / projects

author: NiHaoMike
author_rank: Super Contributor
timestamp: October 02, 2013, 03:59:23 am
content: If you take a 120V induction motor and load it with, say, 60% of its rated torque (assuming rated torque is its peak efficiency point), what voltage should it then be supplied with in order to get peak efficiency under that load condition? How much better efficiency can be expected as opposed to leaving it at 120V?
Induction motor in star config connected to phase, phase, neutral?  - Page 1
Forum section: electronics / projects

author: miceuz
author_rank: Frequent Contributor
timestamp: September 06, 2017, 01:18:19 pm
content: I am participating in reviving an old Soviet era industrial lift in our hackerspace. There is a schematic diagram on the wall displaying all the workings of the system. I was examining it and found out that the motor is never connected to three phases, only to phase, phase, neutral.This is an induction motor with two sets of stator windings for two speeds both connected in Y configuration.How does this even work? Was it a normal practice anytime to connect one leg of Y to neutral?

author: woodchips
author_rank: Frequent Contributor
timestamp: September 06, 2017, 05:35:10 pm
content: Odd, but if the B phase is connected to earth then doesn't make any difference. In aircraft the B phase was connected to the aircraft frame, saving a piece of wire.This won't work too well if you use an RCD!

author: SeanB
author_rank: Super Contributor
timestamp: September 06, 2017, 06:59:29 pm
content: Probably they did this to save using a 3 pole contactor, instead using 2 pole ones. Not the best from the point of load balancing, power delivery from the motor or anything like that, but it will work, and as they have speed controls ( 2 speed motor with a high speed and low speed windings operating on the same rotor, just using different pole spacings) it will at least start and stop smoothly, though your incoming power will be horridly asymmetric as 2 phases will have a heavy load while the third is just idling along.To check if it is a drawing error see if the motor is connected to pins 11,12 and 13 of the controller terminal strip, as they drew in the connections for 11 and 12, while the third phase is not connected through the controller, but instead runs to the external neutral bus. Those connections will be labelled, and it will be easy to see the motor wires on there.Post the whole drawing, interested to see more, plus a bit of the control circuitry as well.

author: miceuz
author_rank: Frequent Contributor
timestamp: September 08, 2017, 08:21:49 am
content: Thanks for replies. Contactor is a three phase contactor and Neutral is switched through it. More of the schematics for anyone interested. It's simple switch logic.

author: hlavac
author_rank: Frequent Contributor
timestamp: September 17, 2017, 09:36:46 pm
content: The switches marked KB (KV) and KH (KN) are mutually exclusive with each other and set the order of the two phases to change the direction of rotation.It is like a single phase motor with starter winding except they use real phase for startup instead of cap generated phase shifted fake

author: miceuz
author_rank: Frequent Contributor
timestamp: September 19, 2017, 06:02:44 pm
content: After further analysis, debugging and change of several key components we have discovered that motor is connected to three phases after all. Not sure if this is an error in schematics or if they did it like this originally.
Induction stove pan sensor, how does it work - Page 1
Forum section: electronics / projects

author: n3mmr
author_rank: Regular Contributor
timestamp: June 04, 2020, 10:08:14 am
content: My induction stove won't start heating a pan with a bottom ø < 11-12 cm (4½-5").Is that something you can adjust by some parameter in some MCU chip or some strap code or something?I CAN live with this. By introducing a trigger pan close by for a second or two, the stove will start heating and, hysteresis!, will keep heating the small pan after the trigger pan is removed.But I'd rather not have to keep a trigger pan on standby.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 04, 2020, 03:36:36 pm
content: I doubt it's going to be very hackable. The control is likely either ASIC, mask ROM, or at least protected (including the label ground off?), and replacing it will likely require knowledge of resonant power control and protection algorithms, in DSP, with hard real-time requirements.But as for how it works, sure -- it's pulsing infrequently, and when it detects a change in the frequency and/or damping of the ringdown, it starts up. It stops when it detects too little load (which might manifest as, too high voltage on the resonant node). These are different conditions so it makes sense for there to be generous hysteresis between them.Is the pot in question, an induction-compatible (usually steel-bottomed) pan, or no?Tim

author: n3mmr
author_rank: Regular Contributor
timestamp: June 04, 2020, 07:11:50 pm
content: All the pans mentioned/used in the test are intended for induction stoves.

author: NiHaoMike
author_rank: Super Contributor
timestamp: June 05, 2020, 02:09:44 am
content: Try offsetting the pan towards the front or sides, that might cause it to couple better and keep the inductance high enough.
Inductive / Capacitive Dummy load - Page 1
Forum section: electronics / projects

author: luky315
author_rank: Regular Contributor
timestamp: September 17, 2012, 07:34:39 am
content: Has anyone a good Idea how to build a Dummy load with 0..0.1F and one with 0..0.01H? I found only resistive Dummy loads but a variable inductive / capacitive load is really useful for stability tests. The load current should be >2A. Any Ideas?

author: Rudolfo
author_rank: Contributor
timestamp: September 17, 2012, 08:05:42 am
content: Ultracaps maybe a solution. There are some with 1.5F but 5V only.Enjoy your design work!

author: luky315
author_rank: Regular Contributor
timestamp: September 17, 2012, 08:49:33 am
content: I need an adjustable load.

author: Rerouter
author_rank: Super Contributor
timestamp: September 17, 2012, 08:55:53 am
content: here you gohttp://tinyurl.com/9qfhh4dthat is for variable capacitance, you will have to size the pot and cap accordingly for your range,and to get variable inductance, you only need to flip the connections of the pot and cap so that the pot is to ground and the cap is to the voltage railhope that helps

author: luky315
author_rank: Regular Contributor
timestamp: September 17, 2012, 02:30:21 pm
content: Thx, i will try it out!

author: ejeffrey
author_rank: Super Contributor
timestamp: September 17, 2012, 02:41:36 pm
content: What frequency and voltage? Do you care about the DC behavior? Does it have to be a true (energy storing) reactance or can you use feedback like a gyrator circuit?Anyway, the simplest solution would be a variac. Just use the output alone (protect the input plug so nobody get shocked) as a variable inductor. For a variable capacitor, connect a large fixed capacitor and use it as an impedance transformer. You will have to look closely at the current and voltage ratings to make sure you don't overload something.
inductive proximity sensor is highly sensitive to temperature - Page 1
Forum section: electronics / projects

author: tuvtuv
author_rank: Contributor
timestamp: October 15, 2016, 09:24:57 pm
content: so the story is that i have a PRINTRBOT 3d printer, and it has this inductive proximity sensor for calibrating the height of the printer head.the printer is enclosed in a cartboard box, and the ambient temperature inside is raised by the aluminum hot bed of the printer. sometimes i print at ~45C ambient, and sometimes at ~80C ambient temperature.The problem that i am encountering is that the proximity sensor is detecting different heights for different ambient temperatures(1.1 mm difference!), and i think that the sensor's circuitry is the main faulty here.does anyone have experience with this sensors and can share some of their knowledge?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: October 16, 2016, 02:47:17 am
content: Aluminum has a large tempco as well.Is that an industrial sensor, the kind with a simple threshold and logic output (usually 24V or switch closure)?Tim

author: tuvtuv
author_rank: Contributor
timestamp: October 18, 2016, 12:44:42 am
content: not sure, i have this:https://printrbot.com/shop/auto-leveling-probe-2/they hide the manufacturer so i dont know the ratings.though the measurement drift only comes to play when temperature of the sensor is high, which comes after half an hour of the plate already being in 110C... so im betting on the sensor being the weak link

author: Dago
author_rank: Frequent Contributor
timestamp: October 18, 2016, 04:06:35 am
content: These types of sensors are not for applications which require accurate and stable measurements like a 3D printer Z-calibration. They are more for "oh there is something there within a few millimeters" -use. I doubt you can make it accurate with any modification that isn't practically rebuilding the sensor (and even then I'm skeptical you can get it to work accurately to within <0.1 mm with a wide temperature range using the inductive sensing principle).

author: voltsandjolts
author_rank: Unknown
timestamp: October 18, 2016, 06:51:24 pm
content: Looks like the sensor might be a LJ12A3-4-Z/BY ...cheap chinese part.https://www.google.com/search?q=LJ12A3-4-Z/BYWhile inductive sensors can be very accurate, a device in this price class won't be.The temperature effect on the electronics and (probably to a greater extent) the change in resistance of the copper sensor coil will likely be the problem. The internal circuit will be measuring coil inductance but probably does a poor job for compensating coil resistance change with temperature. Using a better designed industrial quality product would likely help but perhaps not cure it:http://www.pepperl-fuchs.com/global/en/classid_143.htmAlthough they do cost much more.

author: tuvtuv
author_rank: Contributor
timestamp: October 19, 2016, 02:13:29 am
content: thank you very much for the recommendation!!
Inductive Proximity Sensors - Page 1
Forum section: electronics / projects

author: tomshirvo
author_rank: Regular Contributor
timestamp: July 16, 2014, 05:35:47 am
content: Hi All,I have got a problem with Inductive Proximity Sensors. I build a motor control box that uses Inductive Proximity Sensors and I have been having trouble with the Arduino picking up the Sensor being on or off.The Mosfet I am using is a BSS138.I have attached the specs and the setup of how they are connected.I have 4 of these boards with two sensors attached too them. Only 2 of 4 boards work with the sensors.On the setup picture I have marked M1 and M2;Sensor off; M1: 8.8v , M2: 5vSensor on; M1: 0.625v , M2: 0.68vThis is just one of the boards that doesn't work but the other boards are all different in this measurement.One board that works the M2 when sensor is off is 24v which is what I thought it should be for all of them.I just can't understand why the 24v pullup isn't bringing it to 24v. All I can see is that the Mosfet is stuffed.I have been stuffing around with it for days and I don't understand why some boards work and others don'tI think the biggest problem is that when the Sensor is ON it doesn't pull down to GND it just brings the voltage down to 0.625v. So this must be the problem but I don't know where to go from here.Have I made a terrible design for how the limits hook up or is it just the Mosfets are faulty?Any help would be great.Thanks

author: mij59
author_rank: Frequent Contributor
timestamp: July 16, 2014, 07:22:06 am
content: Hi,Take a look at the data sheet of the BSS138 , max. Vgs is 20 V, no need to drive the gate at more than 10 V.

author: tomshirvo
author_rank: Regular Contributor
timestamp: July 16, 2014, 07:32:09 am
content: So you think I have damaged the Mosfets?

author: AndyC_772
author_rank: Super Contributor
timestamp: July 16, 2014, 07:48:31 am
content: It's easily done. The gate of a MOSFET is insulated from the channel by a very, very thin layer of silicon dioxide, which can be damaged by any voltage above the rated Vgs. They're particularly sensitive to static discharge for the same reason.

author: mij59
author_rank: Frequent Contributor
timestamp: July 16, 2014, 08:07:08 am
content: Quote from: tomshirvo on July 16, 2014, 07:32:09 amYes probably, you can check it with a multimeter, but even if they test good I wouldn't trust them any more.In your circuit a Vgs of 5V will enough to switch the mosfet.
Inductor choice for a switching converter  - Page 1
Forum section: electronics / projects

author: sahko123
author_rank: Frequent Contributor
timestamp: August 06, 2022, 01:36:06 pm
content: My question is pretty simple I want to know if I spec an inductor for my applications maximum Vout and Iout than would the regulator work happily at voltages that are lower than the initially specc'ed voltages and currents. When calculated the inductor requirement is lower (for 5v @ 1A for example) so would this still work with a higher value inductor?For context the power supply will be a linear output stage with a switching pre-regulator working at about Vout+1.5V or so the circuit varies the output voltage of the switching regulator based on the linear regulators set output voltage. I also want it to work from 0-35V (1.5-36.5V for the switching regulator). I will be using the LT8645S regulator for this with a discrete output stage.

author: mag_therm
author_rank: Frequent Contributor
timestamp: August 06, 2022, 05:19:29 pm
content: I am doing similar optimization of L and C today on a pwm.This one is a 13.8 V 20 Amp output at about 40 kHzIn the qucs model, I changed the load resistor to be two.R_min_load is fixed. R_max_load has a switch, On at about 3/4 way through start trace.This is an open loop model with fixed duty cycle setting.https://app.box.com/s/5p6nl1xs724geqs7t81z69s1k8ivnpq9In your case, you should not want the linear stage to drop out under the worst step load increase.
Inductor clearance for noise reduction on a PCB - Page 1
Forum section: electronics / projects

author: Alex30
author_rank: Regular Contributor
timestamp: January 08, 2015, 11:23:17 am
content: So I have a SMPS on my board I am designing which also contains a few components and signals that I want to keep reasonably noise free. My inductor is 22uH wire wound radially mounted and not shielded, it will supply about 12V max at 3A. Is there any rules of thumb regarding how close I can make my traces to the inductor? With a radially mounted inductor most of the EMF would be directed vertically correct? Does that mean that I should avoid having vias in proximity and having traces near the inductor wouldn't do very much?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 08, 2015, 11:31:47 am
content: Induced voltage is proportional to applied voltage (i.e., a square wave more or less), and intercepted by traces going around the axis of the inductor. A signal trace that, for some reason, makes a full loop around the component will get a pretty good amount of induced voltage. A trace dipping near the inductor will still receive induced voltage, but less than if it's fully underneath and around. A trace a good distance away, and along a line radiating from the center of the inductor, will receive little or no induction.Without knowing anything about your circuit, I would guess keeping sensitive traces more than three diameters away from the inductor would be prudent.If you're worried about low noise, you'll also have considerable savings using a full ground plane.Tim

author: Alex30
author_rank: Regular Contributor
timestamp: January 08, 2015, 01:47:17 pm
content: Thanks for the input. Just wondering, how good are those shielded inductors? Do they do the job?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 08, 2015, 03:14:50 pm
content: Who knows... what job needs being done?I still wouldn't suggest placing sensitive traces right beside one, but depending on design and layout, I would very wildly guess it could be up to 20dB better, all else the same (same size and rating of part, same board geometry and trace position).You can play with this yourself using a near field probe (little more than an inductive loop, if you're cheap).Tim
Inductor for a ZVS and SRF - Page 1
Forum section: electronics / projects

author: Neukyhm
author_rank: Contributor
timestamp: December 19, 2017, 04:49:32 pm
content: Hi, I'm designing a regular ZVS that will operate at 113kHz. Inductors of 50u to 150u are normally used as choke for a Mazzilli ZVS, but I have a question, do I have to take care of self resonant frequency?I'm looking for a suitable inductor and almost all manufacturers don't tell the SRF in the datasheet.For example, look at this:https://es.rs-online.com/web/p/inductores-para-pcb/7360980/These radial inductors are used in every chineese ZVS on eBay, and I doubt that the SRF of these inductors (with small number of wire turns) can become a problem.
Inductor measurement - Page 1
Forum section: electronics / projects

author: Jeff1946
author_rank: Regular Contributor
timestamp: February 28, 2012, 01:59:38 am
content: My first post here. After retiring got back into electronics as a hobby. Playing around with converting a camp light to leds which led me to buck boost circuits. Some inductors worked better than others and I wanted to measure them. I ended up constructing circuit which is more or less a voltage inverter. It pulses the inductor to a constant current, then switches off transferring about 80% of the inductor's energy to the output. The square of the voltage on the output is proportional to the inductance. It is quite linear. I plotted the output vs number of turns on a toroid for example. Note a 220 uH inductor gives -5 volts out for the circuit operated on 5 volts. Note R4 and R3 are ordinary resistors that I measured to be about 1% of their value. The frequency is about 11 kHz. For inductors into the mH range you may need to decrease to frequency to allow the inductor to be at a constant current. The switch on the reset pin of the LM555 is to allow you to measure the voltage across R4 to determine the current. I also use this circuit to check capacitors too small to measure on my multimeter. I just parallel them with C1 and note the decrease in frequency. As I am just starting again and I don't have a scope, so I needed something simple. I have tested all kinds of coils. Single turn coils, loudspeakers, transformers (with secondary open or shorted), old AM radio antennas, chokes scrounged from computer power supplies and inductors removed from a laptop mother board. Just need to do a little arithmatic since inductance correlates with square of the output voltage.

author: Rufus
author_rank: Super Contributor
timestamp: February 28, 2012, 03:21:01 am
content: Quote from: Jeff1946 on February 28, 2012, 01:59:38 amNice little circuit to tell you something about inductors.All the inductor stored energy goes somewhere. Did you try some more involved calculation to take into account the effect of the diode and inductor resistive losses?
Inductor Question - Page 1
Forum section: electronics / projects

author: docmur
author_rank: Regular Contributor
timestamp: January 10, 2016, 01:54:37 am
content: I'm doing the layout for a power supply and I'm wondering what is the difference between a chip inductor in a 1210 package and a small coil? They both have the say henry value.

author: georges80
author_rank: Frequent Contributor
timestamp: January 10, 2016, 04:24:58 am
content: You can ask this question too:What's the difference between a 10k 0402 resistor and a 10k 1210 resistor? Both have the same ohms...i.e. there are more parameters that need to be looked at than henries for an inductor or ohms for a resistor or farads for a capacitor or..... There's ideal components (that don't exist) or the real world components...cheers,george.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 10, 2016, 04:42:14 am
content: More space for the power to dissipate over. (The power rating isn't actually much higher, because it's partly limited by diffusion out of the part. Which is limited by its aspect ratio, actually. Which is why 0402 resistors are relatively powerful for their area, and 1206s aren't rated much more than 0603s. Much larger and wider parts have higher ratings, up to a few watts for a suitably made 1218 or something like that.)Obviously, 0402 is smaller, which is important for saving space, and increased frequency response (lower L and C) for RF (as in, 10s of GHz RF).Besides thermal, the electromagnetic properties of a part depend linearly on size, because of the speed of light.Tim

author: sarepairman2
author_rank: Frequent Contributor
timestamp: January 10, 2016, 05:40:46 am
content: inductors have to be the most fancy of passive components.

author: docmur
author_rank: Regular Contributor
timestamp: January 10, 2016, 05:48:55 am
content: Fair enough
Inductor saturation - Page 1
Forum section: electronics / projects

author: Ghydda
author_rank: Regular Contributor
timestamp: April 25, 2013, 10:56:15 am
content: A few years ago I built a small life saver. I basically were getting tired of not being able to properly estimate or easily measure the performance of inductors at high flux rates - i.e. approaching core saturation and even characterize them beyond the saturation point.01 - The user interface. Not much going on.02 - Here you see a coil about to undergo test.03 - The terminals for connecting the DUT.04 - The innards of the box.05 - The control circuitry.06 - The control circuitry from another angle.07 - The control circuitry, more specifically the floating power supply for the MOSFET driver.08 - The control circuitry, the button in the middle means go.09 - The resulting current is passed though some shunt resistors and the signal is tapped and gets fed into a scope.I haven't any schematic of the thing (well it's probably in one of the countless piles I keep), but I suppose it wouldn't take long to reverse engineer it. Certainly faster than digging up the original. Now that you know what the thing looks like on the inside is anyone interested in the schematic and perhaps some snaps from the scope of the thing doing its thing?PS. Is there somewhere a how-to on getting the pics in-line with the text as seen on various other threads?

author: Harvs
author_rank: Super Contributor
timestamp: April 25, 2013, 12:13:57 pm
content: I've done a similar thing but much simpler. Just using a lab supply for the floating supply and an AWG to generate the pulses. So basically just a board with a mosfet, shunt and diode.However, I'd be interested in the schematics. It's always interesting to see how people have solved the various problems in a design like this.CheersBTW, to embed photos you need to use an external photo host like photobucket, then they provide an image link you just copy and paste into the text, which when posted shows up as the pic.
Inductor selection for DC/DC - Page 1
Forum section: electronics / projects

author: atwoz
author_rank: Regular Contributor
timestamp: July 01, 2012, 07:52:55 pm
content: Hello,I'm designing a DC to DC converter, 12v to 5v @ 300mA. I need a 10uH inductor for the job. I was using some big power inductors but I think its overkill and that I could use a smaller inductor.What do you guys think of the following inductor?http://www.newark.com/taiyo-yuden/cbc3225t100mr/power-inductor-10uh-760ma-20/dp/30K5409?in_merch=Popular%2520Inductors,%2520Chokes%2520And%2520CoilsThanks!

author: T4P
author_rank: Super Contributor
timestamp: July 01, 2012, 08:10:43 pm
content: If you only need less then the SRF then of course everything's good

author: free_electron
author_rank: Super Contributor
timestamp: July 01, 2012, 08:11:18 pm
content: without knowing what controller chip you are using , or at least what switching frequency , mode (hysteretic , constant current, contstant on time ) we cannot advise ...

author: atwoz
author_rank: Regular Contributor
timestamp: July 01, 2012, 08:43:37 pm
content: Sorry, the controller is the NCP3170A (from ONSemi) and it runs at 500kHz.

author: free_electron
author_rank: Super Contributor
timestamp: July 01, 2012, 09:45:51 pm
content: ideally you would use a 4u7 part with that thing. i'd stick in a vls3012 or vlf4010 series from tdk.the taiyo you selected will work too. the only thing i don't like about the taiyo is that it is a non-shielded coil. the TDk's i gave above are shielded

author: szhighstar
author_rank: Contributor
timestamp: July 01, 2012, 10:40:49 pm
content: if rate current can meet your requirement, you can select, we can also make the chip inductor.
Inductor shielding - fully enclosed vs alternatives - Page 1
Forum section: electronics / projects

author: findAround
author_rank: Contributor
timestamp: June 14, 2023, 07:31:49 am
content: I'm reviewing an old design to see if I can pinch pennies anywhere. It has 2 switching regulators which use this shielded Bourns inductor:Much cheaper inductors are available with similar specs, and they also claim to be shielded, however the proper ferrite shielding seems to just be on the top/bottom (example TDK-brand inductor below). It's like a ferrite bobbin that has had the windings covered in some kind of goop.My question: For the cheaper, less enclosed style shown, do they use conductive epoxy or something to ensure the actual windings are shielded? Is this shielding comparable to the fully enclosed style of the Bourns inductor? Or is it going to behave much worse, noise-wise? If anyone has had experience with both types it would be great to hear your thoughts.If a non-enclosed inductor like the TDK one shown will be much noiser (trying to keep switching noise out of analog sections), then I'll look for pennies elsewhere.Cheers!

author: Kleinstein
author_rank: Super Contributor
timestamp: June 14, 2023, 07:52:32 am
content: The shape of the ferrite core is not about electrical shielding, but to reduce the magnetic stray field. Conductive epoxy would not make a difference.

author: moffy
author_rank: Super Contributor
timestamp: June 14, 2023, 08:26:58 am
content: If the epoxy rather than having conductive particles had say ferrite particles it might offer some magnetic shielding, but not as well as a solid ferrite.

author: findAround
author_rank: Contributor
timestamp: June 15, 2023, 12:59:22 am
content: For future readers with the same question:After some more research, I've found the second type is referred to as 'semi-shielded' and does indeed use magnetic epoxy to shield the windings.Semi-shielded inductors are cheaper and smaller than shielded inductors, but seem to have a noise performance that is only slightly better than totally unshielded (see graph, from a Würth application note).For my design this means I'll be sticking to fully shielded.

author: moffy
author_rank: Super Contributor
timestamp: June 15, 2023, 02:51:16 am
content: Quote from: findAround on June 15, 2023, 12:59:22 amThanks for the update, it is one thing to surmise, it is nice to get it right sometimes.
inductor sub - Page 1
Forum section: electronics / projects

author: p.larner
author_rank: Frequent Contributor
timestamp: December 05, 2023, 08:28:33 am
content: on page 3 of the attached pdf is a schematic for a bias t,it calls for a 100uh inductor in each unit,i ordered 220uh in error,can they be either used as is or b have say a third of the wire removed and be used?,mine are marked epcos 220uh 0.5a,they are what looks like wire wound on about a 4/5mm core maybe carbon and about 20mm long.

author: moffy
author_rank: Super Contributor
timestamp: December 05, 2023, 09:19:14 am
content: The 220uH value should be fine as long as you don't exceed the DC current value, but resonant frequency is also important as you want that beyond your signal frequency and resonant frequency tends to drop with increased inductance for the same core. Just as a note L is proportional to N^2 if the field is mostly contained within the core.

author: p.larner
author_rank: Frequent Contributor
timestamp: December 05, 2023, 09:26:40 am
content: its for a bias t to power an atu-100 atu,im told the atu-100 has a worse case current draw of 450ma,its for hf ,i use 80m-10m

author: Terry Bites
author_rank: Super Contributor
timestamp: December 05, 2023, 09:27:47 am
content: It will be ok. Its acting as a choke and is not part of an impedance match circuit in this instance.

author: coppercone2
author_rank: Super Contributor
timestamp: December 05, 2023, 09:37:39 am
content: bigger chokes are better. I wonder if you can just add a small choke in series with it that has more ideal behavior to get rid of any problems caused by the larger value unwanted effects

author: moffy
author_rank: Super Contributor
timestamp: December 05, 2023, 09:41:22 am
content: Quote from: p.larner on December 05, 2023, 09:26:40 amI'm guessing that 10m/30MHz is above the chokes resonant frequency which means it will look capacitive, if not then you're fine.
inductor - Page 1
Forum section: electronics / projects

author: rckanta
author_rank: Contributor
timestamp: March 01, 2020, 03:56:53 pm
content: I have a toroidal T90-26 core.I am using this core for designing a boost converter. O/P voltage = 20-21VoltCan this core handle 200 watts?What is the maximum power that can handle this core?
Inductor/Electromagnet used to lift up a magnet? Joules to Newtons or Joules to  - Page 1
Forum section: electronics / projects

author: renzoms
author_rank: Regular Contributor
timestamp: February 03, 2021, 02:22:07 am
content: With interest in using an electromagnet to lift up a magnet.I dove in. I will state general information. The set up is unknown but I'm interested in the physics/electrical engineering involved in calculating the amount of ______ needed to lift up a mass (magnet with magnetic strength x).I reviewed "electromagnets". I see an inductor produces a magnetic field, a summation of the contributions of electrons and we get some equations.Regarding inductors, Energy is .5LI². We can adjust the power/energy/magnetic flux in an inductor by varying the voltage/current/turns, etc.Also since V = dϕ/dt, maybe we can integrate velocity to find the magnetic flux or something but idk if magnetic flux is relevant to lifting a magnet on the ground.So I found a link to the an equation expressing the force between two magnets in Newtons homework and exercises - calculate force between two magnets - Physics Stack ExchangeI see magnetic force is measured in Gauss.I've nearly finished relearning Classical Mechanics, so I'm thinking about using F = ma, and I'm not sure how the inductor/"electromagnet" ties into this nicely.I don't know how to convert an inductors properties into Gauss, nor express it as a function of distance, and I think you guys can help!I considered using F = kqq/R or some other attraction law, but still idk how to relate an inductor and it's Joules or other properties to "magnetic strength" I can use in a kinematics analysis.
Inductors for line voltage filtering - Page 1
Forum section: electronics / projects

author: XaviPacheco
author_rank: Regular Contributor
timestamp: July 21, 2019, 09:42:06 pm
content: I would like to usethese inductorsat the input of a three phase rectifier like shown below for a low voltage power supply. Is it a good practice to do this?

author: Stray Electron
author_rank: Super Contributor
timestamp: July 21, 2019, 09:53:30 pm
content: What's on the output of the rectifiers? Inductors alone are usually not a good idea for filtering because of the dv/dt factor. In other words, they generate LARGE voltage spikes if the load isquicklyswitched on or off. The voltage that they generate is proportional to the inverse of the switching time and is usually substantial. Inductors need to be used in conjunction with with capacitor on their input or their output (or both). Also inductors tend to be very large, very heavy and very expensive for anything that draws much actual current or power.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 22, 2019, 01:54:56 am
content: Quote from: Stray Electron on July 21, 2019, 09:53:30 pmIf the load is another inductor (choke input filter), at worst the peak voltage is an inductor divider between mains and DC bus. So, nothing important.Even if the load is hard switched, the peak voltage is limited by the rectifier diodes, which for a three-phase rectifier I'm guessing would be chosen at 1kV or higher, and should be chosen for avalanche capability if this applies (if it's a bog standard cap input filter, who cares).As long as the current ratings are adequate for the application. Mind that, if peak current draw exceeds Isat, you will momentarily lose the benefit of that inductance.Tim

author: XaviPacheco
author_rank: Regular Contributor
timestamp: July 22, 2019, 02:19:55 am
content: This is from a design a posted some weeks ago that I'm trying to improve. See image attached. The three phase input voltage can go up to 480 VAC. The bridge rectifier is built uponthese diodes. The three line inductors L1, L2, and L3 arethese onesand I would like to replace them withthese ones. The original fuse is rated at 125 mA/250V, but I think it's underrated so I would change it to 500mA/ 1A/600V.

author: SiliconWizard
author_rank: Super Contributor
timestamp: July 22, 2019, 12:18:19 pm
content: You can take a look at this kind of off-the-shelf filters:https://www.te.com/usa-en/product-CAT-C8114-AY91.html?tcpns=CAT-C8114-AY11%7CCAT-C8114-AY91%7CCAT-C8114-AY61%7CCAT-C8114-B349%7CCAT-C8114-F299C%7CCAT-C8114-AY18%7CCAT-C8114-AY68Excessively expensive, but the drawings include a schematic so that would give you an idea of how it's done.Basically Pi LC filters.
Inductors in CS5171 SEPIC application diagram - Page 1
Forum section: electronics / projects

author: pjhenley
author_rank: Contributor
timestamp: July 28, 2018, 07:38:18 pm
content: Attached is one of the application diagrams from the CS5171 datasheet. I'm looking at the two inductors in this diagram and I'm wondering: why is one dot solid and the other empty?Datasheet:https://www.mouser.com/datasheet/2/308/CS5171-D-111782.pdf

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 28, 2018, 08:27:42 pm
content: Doesn't mean anything electrically.Typo?Tim

author: sdouble
author_rank: Frequent Contributor
timestamp: July 29, 2018, 12:39:17 am
content: what do you mean by empty ? non populated ?those are coupled inductors. The use of coupled inductors improve the efficiency of SEPIC designs

author: pjhenley
author_rank: Contributor
timestamp: July 29, 2018, 06:26:38 pm
content: Look at the phasing dots on the schematic. The inductor at the top has a dot that is white on the inside with a black outline. That's what I mean by an empty dot as opposed to a solid dot. Look at the other inductor. it has a dot that is black on the inside, that is, solid. I have seen solid black dots used before. I've never seen a white dot with black outline.

author: David Hess
author_rank: Super Contributor
timestamp: July 29, 2018, 06:29:52 pm
content: They are phasing dots for if a coupled inductor is used which is not strictly necessary. The draftsman just ran out of ink.
Inductors in DC to DC Regulators - Page 1
Forum section: electronics / projects

author: SnoopKatt
author_rank: Contributor
timestamp: April 15, 2015, 07:11:52 am
content: Hi,So I'm building a 3V to 10/-10V supply from a TI TPS61093 that will be pulling 200uA (the circuit is figure 16 of the data sheet). It recommends a 10 uH inductor, and looking around, they come in tons of different sizes. Space minimization is important for this, so that 0603 form inductors are appealing, but I'm noticing they have fairly high resistance compared to the larger coil wound ones that are normally in DC/DC step ups. Since I'm not drawing a lot of current, will something with a 300-600 mili-ohm resistance compared to 60-80 be ok?Thanks!

author: SnoopKatt
author_rank: Contributor
timestamp: April 15, 2015, 01:10:35 pm
content: It's just using a 200uA current source in series, so there's no crazy peak current. Thanks!

author: XFDDesign
author_rank: Frequent Contributor
timestamp: April 15, 2015, 04:44:52 pm
content: But there will be "crazy peaks" - it's a part of the nature with switchers.Your 200uA is anaverageoutput. It's what you get when the time-on-time-off (Duty cycle) comes out to some particular wash. This is why it's spec'd in the datasheet based on your switcher's frequency. If it's a very rapid rise and fall, you'll have huge peaks with 200uA average. If it's a slow rise and fall, it will be small peaks. This is the "fun" of switchmode design.

author: SnoopKatt
author_rank: Contributor
timestamp: May 19, 2015, 03:14:45 am
content: Just to update everyone, the smaller inductor was a success! We hooked up the current source to the +10V/-10V supply, and it successfully drew 200uA. Messing around with it, using more than 1 mA seemed to make the voltage booster drop out to about 1-2V, so definitely not a good solution for higher current, but for this application it seems to work well.
Industrial 'made in Sweden' power supply, with big power bank! Or what is this!? - Page 1
Forum section: electronics / projects

author: patrikcarlsson
author_rank: Newbie
timestamp: February 22, 2015, 05:36:54 pm
content: Hi everybody!Today my dad was throwing out lots of stuff from his garage, so I scored this thing! What is it? Well, it comes from one of many "switching stations" (Google Translate gave me this) which are placed next to the railway here in Sweden, making the rail system work! My dad works with this stuff, so I think he took it from one of these small stations when they removed one. My question here is, may I have any use of it? Is it worth anything? I'm very curious about the 12 large capacitors/batteries in this thing, as I simply don't understand what they are used for! I guess it could be a large power backup? Or are these 12 things some of those so called "super capacitors" I have seen people have fun with on YouTube? I don't understand why there would be a capacitor bank in a power supply like this, but maybe you guys know!Here it says about a 8Ah battery capacity, so I guess it's a battery backup. If so, do you have any ideas of what I can use this for? And what type of battery are used in this? Some sort of LiIon or what? Are they worth anything?Should I just throw the electronics away and use the case as a fire proof container for LiPo charging, or is this worth enough to put it up for sale, or do you know what I can use it for? I guess it would be quiet useful as a power backup for stuff like my LiPo chargers, but maybe there are more uses for this?

author: langwadt
author_rank: Super Contributor
timestamp: February 22, 2015, 05:46:20 pm
content: first hit on google:http://www.eldaco.se/service_support/pp_manual_eng_rev2.pdf

author: SeanB
author_rank: Super Contributor
timestamp: February 22, 2015, 06:01:16 pm
content: It is a 24V power supply with a battery. Battery likely is going to be dead from lack of charging or old age, but the charger is likely to still be in good order. It likely is usable as a 12V charger, or can be used as a 24V charger as is.Likely if you do not want it then use it as a lipo charger housing after stripping the batteries out. Old lead acid cells should be sent for recycling.

author: helius
author_rank: Super Contributor
timestamp: February 22, 2015, 06:38:17 pm
content: Those black cylinders are Hawker Cyclon lead-acid batteries. They have a longer life expectancy than regular SLA type but may be toast if they have been off-charge for several years.http://www.digikey.com/product-detail/en/0819-0012/842-1009-ND/2003841

author: SL4P
author_rank: Super Contributor
timestamp: February 22, 2015, 08:20:33 pm
content: A guess...Battery charger for a golf buggy/wheelie thing? Or something like that.
Industrial Automation Analog Input Training Handout - Page 1
Forum section: electronics / projects

author: Bootalito
author_rank: Unknown
timestamp: October 30, 2017, 05:27:07 pm
content: I prepared a handout that I use for internal training for industrial automation / control systems engineers to help explain the different Analog Input card differences, when to use them, how to wire them etc. We almost exclusively use Allen Bradley hardware so again the handout has a specific target audience. But its generally applicable for electronics in general, so I'm sure some people will be able to extract some information from it. This is a handout that really should be turned into a power point, then stripped down to bullet points with circuit diagrams added. But I simply hand out copies to everyone then read it top to bottom (while stopping to interject things of course), which isn't the greatest way to present material.https://www.dropbox.com/s/tvi2934ou99ubw6/Single%20Ended%20vs%20Differential%20Transmitters%20and%20Inputs.docx?dl=0The owner of my company asked me to do something similar for counter cards which when complete I'll post as well.
Industrial Grade inverter - Page 1
Forum section: electronics / projects

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: November 02, 2020, 11:58:40 am
content: Hi,I want to buy a 3000W industrial grade (-20 to 60C working temperature) Inverter, input 12-24V output 230VACDo you know and recommend any brand or model?

author: akimpowerscr
author_rank: Regular Contributor
timestamp: November 02, 2020, 12:14:16 pm
content: I don't think "industrial grade" means much.....You have dozens of industrial grade inverters on Amazon for less than 1000 US§ ..... However, I doubt the quality, reliability and technology of such inverters.You should consult the catalogs of renowned power electronics manufacturers to find what is right for you.I think it would be easier to find a good quality on-line ups than a single inverter.
Industrial PCB Production: Etchant? - Page 1
Forum section: electronics / projects

author: BurnedResistor
author_rank: Regular Contributor
timestamp: September 18, 2017, 04:44:00 pm
content: Dear All,Having to write a science report, I was wondering what kind etchants are commonly used in PCB production. Does anyone have any insights?Common hobby etchants I found where:ammonium peroxydisulfate (NH4)2S2O8 a.k.a. ammonium persulfateFerric Chloride a.k.a. Iron (III) Chloride (FeCl3)Sodium Persulfate Na2S2O8Are these also used in industrial production?Thank you!

author: jpanhalt
author_rank: Super Contributor
timestamp: September 18, 2017, 07:38:36 pm
content: Chemcut -- a manufacturer of commercial etchers -- states that about half of the devices it sells are alkaline etch (ammonia + cupric chloride) and about half are cupric chloride. I suspect what remains are ferric chloride or more esoteric etchants (http://www.chemcut.net/technical-info). Depending on location, ferric chloride may be used more, but I have no data to support that.

author: nctnico
author_rank: Super Contributor
timestamp: September 18, 2017, 08:04:26 pm
content: AFAIK cupric chloride is commonly used because it can be re-used indefinitely and the 'strength' can be kept constant.
Industrial POT replacement - Page 1
Forum section: electronics / projects

author: jamorais
author_rank: Newbie
timestamp: December 03, 2022, 07:03:49 pm
content: Hi Guys.I have a situation where a customer has some old industrial rectifiers that were controlled by a Pot.Now i'd like to control them with the PLC but the pot circuit pulls too much current and the 0-10v outputs of the plc max at 45mA so, if i connect directly, the voltage drops on the plc output.if i connect an external power supply and provide the 0-10v it works fine.Now i've seen some ideas on the internet with FET+OpAmp with feedback to get linearity, i saw digital pots which could be controlled with digital plc outputs (up down steps).An LM317, with 24v on the input and the 0-10v plc output to control the adjustment so i get 0-10 on the LM317 output. Although this uses de 24V power supply. Not ideal but it works.this interesting one which gives me galvanic isolation too, which is important in this situation:https://www.edn.com/use-a-photoelectric-fet-optocoupler-as-a-linear-voltage-controlled-potentiometer/What do you guys think? Any ideas?

author: bidrohini
author_rank: Regular Contributor
timestamp: December 06, 2022, 06:50:33 am
content: Hard to give an accurate idea because these type of projects often needs to be done in trial and error basis. I think it's better to try with both LM317 and LM358. After that, you can compare their performances.

author: abyrvalg
author_rank: Frequent Contributor
timestamp: December 06, 2022, 07:12:45 am
content: Depending on PLC processing power, perhaps you don’t even need linearity so much - just design some curve translation block and insert them before each pot output.

author: Jeroen3
author_rank: Super Contributor
timestamp: December 06, 2022, 07:24:28 am
content: Investigate the input circuit a bit, you can probably use a current output and perhaps some additional parallel resistor.Then just a universal MCR-SL-UI-UI-NC will be fine.

author: Terry Bites
author_rank: Super Contributor
timestamp: December 06, 2022, 01:57:42 pm
content: This circuit I imagine you've already come across. Its just an amplfier with boosted current capabilities. Vo=(1+R1/R2)Vc, here Vo=2CvC1 and R3 keep this circuit stable. A rail to rail opamp is needed here. Just about any N-Ch power mosfet will work.Cv can just be a voltage or a lowpass filtered PWM signal. Isolating PWM is easy, just use a photocoupler.