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  1. Hello. I'm building a 12v bluetooth speaker and am trying to design the battery and charging system. I'm thinking about using 3 of the Panosonic NCR18650B in series to start, and then perhaps upgrade to another 3 pack in parallel later if the battery life isn't good enough. This is my first experience building something with Lithium batteries and it's a bit intimidating. I've done quite a bit of reading, but i wanted to come here and ask a few questions in hopes of getting this right the 1st try. more: eco dream city The BMS i've chosen shows "charge/discharge" on one of the images for the P+ and P- terminals. I'm hoping this means that I can connect my incoming power AND my load (12v amp & bluetooth module) to those terminals and it will allow me to use the amp while charging. In the description it says "Charge with 12.6-13.0V Power supply (not included)." With that in mind, here are my questions: 1) I was working under the assumption that i would need a battery charger or charging circuit before the BMS, but the description makes it sound like i can just put a power supply directly to the BMS. Would one of the 12.6v li-ion plug-in style chargers (like this one) be ok to use with this BMS? Would a charger like that cause interference noise in the speaker? more: dự án mỹ đình plaza 2 2) When connecting the power and load to the BMS, do i need any kind of diode in line with the load? 3) I was planning to get the protected versions of these batteries, but is that necessary if i use the BMS and charger that also offers protection? If I was to use the protected batteries, does that eliminate the need for the BMS? I have built NiMH chargers using the Maxim ICs in the past that allow for charging and load as the same time without any interference, and I know that option is available for Li-Ion as well. However, i would REALLY like to avoid making my own charger if possible. more: dự án eco dream Thanks for any advice you can offer!
  2. I am new to both this site and electronics, and everything I know about components and how they work (which is near non-existent) I have learned in my spare time. I am planning on buying a modified sine wave inverter to have for emergencies and to power miscellaneous items in my car. I don't plan to use it on anything with electronics, because I know that they don't always play nice together. Knowing that capacitors help smooth voltage (at least I'm fairly certain anyways) how would I calculate the correct capacitance for a known load? This would be partially for increasing efficiency and also incase I am at a job site and need to recharge my power tool batteries. Also, if anybody could explain to me as to why I always hear that modified sine wave fries battery chargers, it would be greatly appreciated...actually any information even remotely related that is explained in laymens terms would be very helpful. more: chung cư eco dream, bán chung cư mỹ đình plaza Thank you to anyone and everyone in advance that can help
  3. Hello I have this circuit built into a PCB, and its a little strange. The fact is it works some times and not others and I am unsure of why... more: chung cư pcc1 Power_Button+ & Power_Button- to go a simple low power switch that is designed to switch the power to the rest of the circuit. And it does work (sometimes). The mosfet is a CSD19503KCS with a Vth of 2.8V. When I take a scope to the gate pin it says 0V even when I flick the switch on or off. But, the power is still on current is flowing through the circuit @ 0V on gate!! I did not think there were any min values for the drain/source voltage but maybe I am wrong... It has currently decided not to work so I cant get the voltages when its working OK. more: dự án hh2 dương nội D2 is a 45V TVS Thanks Tags: eco dream nguyễn xiển
  4. Connect a 12 volt taillight, turn signal or any small 12 volt lightbulb to your 6 volt battery. Now connect a 12 volt charger to the 6 volt battery. Voltage at battery will be 6.7 to 7.02 volts. Unscrew the three caps on the 6 volt battery and observe the bubbles of hydrogen gas leaving the electrolyte from each cell. The cell on the + side will stop bubbling first as the 6 volt battery reaches full charge, then the middle cell will stop bubbling, then the cell on the -- side will just barely be bubbling when fully charged. The small light creates a drain and the charger continues to charge that cell. more: xe 2 tan hyundai A 12 volt battery connected to a 12 volt charger will cut out at 14.6 volts. Then the 12 volt battery will settle to 12.7 volts after 30 minutes. A 6 volt battery connected to a 12 volt charger with the small 12volt light WILL NOT cut out because you want a fully charged 6 volt battery to settle to 6.4 volts. You must observe and manually disconnect the charger. more: giá fortuner 2017 Do not connect the small lightbulb in series because the 12volt charger will sense too much resistance and then indicate a fault after two minutes.
  5. I have a laser spirit level which takes two AAA cells. they slide lengthways into the side of the level, one positive end first, one negative end first. the battery compartment cover has a sheet of copper which connects the two exposed cell ends together, so that the cells end up in series once installed. more: xe dongben It occurred to me that with a 7 year old lad wandering round, I might be sensible to avoid leaving a laser device around that could be easily turned on and stared into. so, I took out one cell and turned it round so that both cells had the same polarity end facing the cover. I can't recall if I had the + or - ends both sticking out. figured, it might prevent an inadvertent retinal burn whilst still leaving the level ready for use at the drop of a hat, with the only inconvenience being, having to reconfigure the cells before use. at this stage I thought, hell, what you doing messing around, just stick the darn thing in the shed & lock the door, problem solved, no need to worry It did start me thinking though.. what actually would happen if one did that and then left the device lying around for say 6 months, with the device's 'on' switch in either position? simple thinking, two back to back fresh cells of the same type would cancel out, no voltage across the resulting battery, no current flow, the cells would just sit there and do nothing, as if they were entirely disconnected. they'd maybe discharge slowly at the normal self-discharge rate but otherwise would remain as ready for action as if they had been left in the unopened packet. more: hyundai 2 tan but i bet it's not as simple as that.. I mean if one cell were slightly more highly charged than the other then you'd have some small voltage being applied to the device, not enough to turn it fully on maybe, but perhaps enough to allow a nonsignificant flow of current. is that likely to be a situation that would be self extinguishing as the more highly charged 'winning' cell discharged more rapidly than the other? or would it go the other way with one cell doing some kind of runaway self-flattening? Could you end up damaging the device doing this, I guess the worst you could end up with would potentially be 1.5V the wrong way round across a circuit expecting 3V in the other direction (maybe for an extended time) Is it a recipe for a leak in the battery compartment? Thoughts?
  6. Alright, this one seems like a gimme, but look closer (yes, at my super crappy picture). These do not seem to obey normal band nomenclature. The top resistor colors from L-R Red - Black - Brown - Gold - Orange. Normal 5-band decoding would say this is a 20.1Ω resistor with tolerance orange. Nope, this came marked as a 200Ω, and measures out accordingly. Second, orange is not a tolerance marking according to my charts or those I found during a web search. So this one seems like perhaps the first three colors give the resistance (as in a 4 band), the gold is tolerance (5%) and orange is temperature coefficient. The bottom resistor reads (L-R) Brown - Grey - Black - Gold - Orange This can be particularly confusing as if you use standard decoding, you come up with 18Ω (which measures correctly) and again, orange tolerance. However, if you use the scheme from the first resistor, you also get 18Ω but with an orange temperature rating. This is the first I've run into this discrepancy. Is this a carbon comp thing? read more: gia xe toyota fortuner 2017, xe tai 1.9 tan
  7. I went to the library, I got a book on electronics for inventors, and a book on electronics for hobbiests. Great for me, whoopdy doo for you. Each book had a chart in it, that gave capacitor code reading a whole new meaning to the word confusing. One was fairly clear, It has little pictures of ceramic discs that have lots of different things written on them and says, the markings will vary with the manufacturer...and explains the digit 1 digit 2 digit 3 and the multiplier thing... The other defined a couple of types, that are usually fairly specific in their markings, but the rest are not hard to figure out, but its up to me to decifer. K. I have a small pile of little ceramic discs, and I need a .1uf and a 50uf; but with everything from 222k to 104z on them. The inventor book says that capacitors are usually marked with pf.. Great for you, whoopdy do for me. Well lets see if that's true----- a 104 would be a .000104uf and a 222 would be a .000222uf if I am getting my math right. I am not really sure about my coding ability for some reason, so I am seriously concidering buying a capacitance meter. But then again, I have heard stories about these also... That some are about as useful as the code sheet. So what is the buzz on these "capacitance meters" anyway? Are they a waste of my time, and a codesheet with buttons? Or are they a "good investment" that will tell me when I "hit a .01uf" in my testing of the pile of small discs? Tags: ringtone free download, https://tonosgratis.mobi/anuncios
  8. Hi everyone, This is my first post, and I come to you all with a question about LEDs. I recently got some (10 pink, 10 red, 10 blue, 10 orange) from eBay, and I'm having trouble getting them to work. I'm wondering if I'm using too little voltage. The description said 9v-12v DC. So, I tried using a 9v battery, with some 9v battery connecters I got off of Amazon. I stripped the red and black on both the connector and lights (they were pre-wired), and connected everything, and got nothing. I went back to the listing page and found the chart that I've attached to this message. Does the chart mean I need to use a 12v power source instead? If that's the case, where can I go about getting one? I see Amazon has these A23 12v batteries - will those work? Or, do I need, like, a car battery or something? Are connectors available for A23 batteries as well? I didn't find anything after a quick search on Amazon. These LEDs are for a photoshoot on Saturday. So, I'm hoping to have a solution before then. If anyone knows more about this than me, and would be so kind as to reply, I would truly appreciate it. Hoping to hear from all of you! Thanks! Tags: new ringtone download free mobile, samsung ringtones 2017
  9. Hi All, I’ve been assembling some small amplifier circuits based upon the TBA820M, LM386N, TDA2822M devices and as a starting point have used the test circuits in the datasheets. My question is regarding the capacitors in the circuits and am unclear on the difference of the non polarised capacitors. With that regard which type of capacitors should be used in these type of circuits? E.g. can a 0.22uF can be a metalized polyester, a ceramic, a tantalum or even a non polarised electrolytic? I am building up a stock of components including capacitors and am fine with electrolytic's but it’s the other types i’m confused about. I seem to have quite a few ceramics & less metalized polyester but that’s about it. When not stated on circuit diagram how do know what flavour of non electrolytic's to use? Another question: Why are polystyrene capacitors significantly more expensive than other sorts, what are they required for and do I need to add some to my stock? And how about the little box shaped polyester capacitors with the very short legs - do I need them? BTW: Apart from small amplifiers I'm doing some experimentation with 555's, logic and Arduino. Sorry for the rambling. Any thoughts and comments would be most welcome. (If there is an online guide to this subject, a pointer would be appreciated) Sincere thanks Tags: message tones download free, tonos para celular gratis, funny ringtones download free
  10. Hi, I am looking for a rotary switch/encoder or a pantometer that works via the USB HID class. So for each position of the rotary switch it should output a unique string via USB? I'll need a switch/ pantometer and a board that translates the serial input into USB (HID class - cause I cannot install any drivers on the media-computer I am using). Ideally 10 or more positions. An alternative would be a rotary switch that ouputs GPIO data, in that case I would of course only have 8 distinct positions. Some words about what I intend to do: I want to create some sort of "wheel". If its turned it should trigger videos/images on a media-computer. As already mentioned: I cannot install any drivers, but the computer works with USB HID devices and also has GPIO. Until now I am doing exact the same thing with an USB RFID sensor - it works fine, but could cause some trouble, because the RFID tags aren't read correctly each time, so I thought about doing it with a mechanical switch. I have looked quite a while now, but couldn't find anything useful. Does anyone know products to do that? Thanks a lot Tags: descargar tonos, nhac chuong mien phi, message tone
  11. I see on the internet where most manufacturers recommend a max charge voltage or absorption voltage of 57.6v-58.8v for flooded led acid battery. I have a nova 48v 3000watt 110vac pure sinewave inverter that allows a max of 57.1v input voltage. Because of this i cannot set my charge controller to 57.6v-58.8v according to what most manufacturers said you should charge a 48v flooded led acid battery to. If I set the charge controller to cut off at 57v or 57.1v which it will go in the absorption stage at that voltage and then afterwards it will cut down to a float charge voltage of around 54v will I still be able to fully charge the flooded led acid battery? Is there any pros and cons with charging the 48v battery bank at a lower voltage setting than the recommended charge voltage which is 57.6v to 58.8v? Is charging at the lower voltage setting increase my charging time to fully charge the battery? is charging at a slightly lower voltage better for the battery? Tags: descargar tonos gratis, nhạc chuông miễn phí, download iphone ringtone for free
  12. Hi all, found this interesting yyd-3 module which is some sord of four channel "silicon" relay. It has four (817) optocouplers who's open collectors (Emitter:GND) drive (VCC:10M->G->10K:GND) the gate of an IRF5305S (used as a high side switch). I looked at the datasheet of that P-FET but am unsure if it will switch reliably at VCC voltages down to 3V. Those FETs need to switch minimum 100mA, at max 1.2A (all at 3V) and will operate at 70C temperatures. They are used as relays, i.e. to power lights etc. Has anybody worked with these FETs or does anybody know if there is a minimum (VCC) voltage or current required for these types of hexfets to switch on reliably? Thanks! Tags: descargar tonos gratis, iphone ringtones download, descargar sonidos para celular
  13. Hi All, After recently getting an Arduino Uno kit i'm starting to get back into electronics. I've always had an interest and have various bits of kit and have a small stock of through hole components. I'd like to be in a position where I can start the majority of projects using components from stock. So I'm looking to add to my existing stock and would be really grateful for someone to tell me what I need to add. Typical projects will be based around Arduino, Microcontroller, LED, Small audio amps, etc For my project inspiration i'm using the web as well as the following books: Make Electronics, Electronics for Dummies, Arduino Workshop, Arduino for Dummies. My current stock is: Resistors: 1Ω, 2.2Ω, 10Ω, 22Ω, 24Ω, 33Ω, 47Ω, 50Ω, 56Ω, 68Ω, 100Ω, 120Ω, 150Ω, 200Ω, 220Ω, 250Ω, 300Ω, 470Ω, 560Ω, 680Ω, 680Ω, 1K, 1.2K, 1.8K, 2K, 2.2K, 3.9K, 4.7K, 5.1K, 6.8K, 10K, 15K, 22K, 39K, 47K, 51K, 68K, 100K, 220K, 470K, 680K, 820K, 1M, 10M Pots: (K) 1K, 2K2, 5K, 10K, 10K, 47K, 50K, 50K, 100K, 430M Capacitors: Electrolytic (uF): 0.47, 1, 4.7, 10, 47, 100, 220, 470, 1000 Non-Polarised (nF) 0.2, 0.22, 10, 33, 47, 100, 220 Semiconductors: 2N3904 Transistor NPN 2N2369 Transistor NPN BC549C Transistor NPN BC557B Transistor PNP IRF540N N Channel MOSFET NE555 Timer IC BTA16 Triac, 600V LM358AN OP amp, Dual TL062CN Op Amp, Bi FET LF13741N OP Amp, J-FET Mono TBA820M Audio Amp, 1.2W LM386N Audio Amp, 250mW TDA2822M Audio Amp, Dual LM371T Voltage Reg, Adjustable +1.2 - 37V @ 1.5A L7805CV Voltage Reg 5V 1A L7915CV Voltage Reg -15V 1.5A ML7915A Voltage Reg -15V 0.5A 7915A Voltage Reg -15V 0.5A L7812CV Voltage Reg 12V 1.5A BS-B Bridge Rectifiers 1N4001 Diode BYX79C Diode, Zener All shopping list suggestions gratefully received! Many thanks, Tags: gratis tonos de llamadas, funny ringtones, tonos divertidos para gratis, iphone ringtones download
  14. Hi, I have 12 volt /10 amps solar charge controller. As per design it will bulk charge at 14.4, absorb charge is between 14.4 to 14.6 and after that it will enter into float mode. when charge controller enters into float mode its voltage will step down to 13.7 volt and led will starts blinking. I observed that, when i put power supply (to simulate solar panel) voltage above 14.6 volt, led is blinking which is normal but when i measured voltage across battery terminal using multi-meter then voltage is fluctuating between 14.7 to 13.7 and also between these range. Is this normal or it require a fix. NOTE: All this observation is while charging. power supply and battery is connected to the charge controller. Load is switched off. I observed the same when i connect solar panel instead of power supply. Can anyone guide me on this? Tags: ringtones download, alone ringtone download song, download classical ringtones
  15. I have a wacom cintique 24HD, an expensive monitor i got fairly cheap in a scam of sorts, i was sold a dying monitor, the tubes are on their last legs, they only really reared their weakness once it got really cold, which took a while since we had unseasonably warm weather from since i bought the monitor over a year ago until now. I cant send it in for repair because im poor and i have no warrantee, the thing weighs a ton, and i have to cover shipping, with no guarantee itle be fixed. Anyway, monitor works fine (displays a picture) but the backlight, which operates almost completely independantly, often fails to start and leaks HV from the cables, indicating that the tubes are bad, i tried replacing the capacitors but it didnt work, although oddly heating the capacitors up sometimes helped it start i think this was just coincidence, or, causing leakage that helped somehow. Ive opened the monitor several times. everything is attached to an aluminium plate which sits on the backlight i asume, which appears to have its edges all wrapped in something like packaging tape. There are 6 inverters powering 6 pairs of leads, i asume that there are 6 lights. what do i do? is there a proper procedure for replacing the tubes? like, in general for backlights? Ive been told i should be able to just yank it out and stick in a new one that its that simple. Is it? if it comes to the point i cant identify the tubes ill just replace them with LEDs, when one tube fails it doesnt cause uneven lighting. The driver just takes PWM and has a single feedback port which outputs 5v as long as the inverters are running to indicate its ok. So, how should i go about taking apart the backlight and accessing the tubes? This is actually a common problem, this model of monitor failing in this way after a while. I forgot to mention that i need to do this non-destructively, ive spoken to wacom, they said as long as i dont cause damage suggesting i caused the failure, they will repair it. I want to keep that option open which is why im not just arbitrarily cutting and prying things apart. Ill post some photos if neccesary. Tags: ringtones downloads for mobile, tai nhac chuong kinh di mien phi, iphone ringtones