pcb etched, resist cleaned off, bandsawed to rough shape .. this will have 4 airwires, bit of a quick one.
build completed, not happy with the usb lead position but will see how it goes, now just have to code it..
Looking at your set up Stoney, you will be able to take the reading under load connected to the PV? If that's the case I will buy one!!!
yeh mate, i made a mistake in that I designed the pcb to use an MCP6001U but installed an MCP6001, so my current monitoring buffer is a nogo, so just fudged it to read the current across a 0.2 ohm in series. The plan is it will run via hyperterminal or some other terminal program, take you through a test procedure and then display a report. I shouldnt rush these things, spent more time sussing out a couple of booboos than if i spent time sorting it at the start. its currently working to a stage of displaying raw a/d volts and amps. the plan was to use a capture compare module to determine PWM duty cycles very accurately but just realised it needs another opamp to do that accurately .. next version..
it seemed a relevant one to hijack Output currently using an ego battery and a crappy old HV atty thats hard to cook.. Using my ego twist cranked up with ego C atty ..
embedded control ? done supplys, ethernet, BACnet, CAN bus, rs485, chemical sensing, RF devices, motor control, touch LCDs,LED signage, emergency signage .. all on PICs but thinking if migrating to Arm stuff .. next touch LCD air con controllers i need to do require more graphics.
the battery connectors i buy 4 at a time from juicewhore, the atty connector was pulled off an old 510 atty.
new additions .. compiled in calibration factor, now accurate to 3 digits compared to a fluke. averages voltage readings every 10mS in a linear mod and every pulse in a PWM mod. approximate battery life remaining Vrms corrected, still inaccurate as needs to do a square root of the duty cycle and loses resolution due to integer math duty cycle accuracy increased to 1:10000 as I needed better accuracy. if pwm between 75 and 95Hz assumes its an eGo .. why not.. sample output, battery straight off charger .. reading from a 900mAh used for some time
very nice, unsure of the relationship of Hz Duty Cycle = 80.47 % Ipeak = 1.467 A could you explain stoney?
freq 83 Hz, so typical ego it pulses on 83 times a second. duty 85% .. the output is on 85% of the time in each pulse. Ipeak (and Vpeak and Wpeak) is the current measured when the pulse is on, different to the average or rms current of course as its not taking into account the off time. Irms is actually Ipeak * sqrt (duty cycle)
lol, diggy was meant to be 'digital' . but ciggy diggy rhymes and sounds silly so i went with it. decided to make 10 or so of these, wont be available for a couple of months as I want to wait for my 3D printer to arrive to print a casing. next version much smaller .. been using it with a cable between the USB and sensor, much nicer. I know this is a particularly useless and nerdy device, stuff like this is my hobby tho
how would the readout compare with a 18650 mod? im assuming most if not all won't "pulse" like an eGo it is impressive! you could make some awesome mods with your variety of skills! (probably already have but im new to the forums!)
no, it displays data as in post #6 as a linear device then. i have made a couple of prototypes .. they are the tick v1 and tick v2 that appear in my sig. I might ressurect them when my 3d printer arrives as casing is what stopped me dead in my tracks, i have a few unique features in mind that mean a complex case interior.
so gave up on my dodgy 510-ego adapter and using a 510 extender doohickey I got the ego C atty to work on the tester, using a ego twist was getting a big variation in power .. from .. to This is a no go ! so stuck it on an oscilloscope and that explains it ! according to my CRO a 1.20Vp-p excursion at CRO 79.45kHz, Vrms = 3.54V the difference in atty resistance will be due to the different sampling time for the voltage and current monitoring, so now i need to think of whether to fix this in software, I think i might try and get themin and max sampled, apart from the frequency .. my little tester should be able to explain this if my software has enough grunt..
experiment done for mikey mike mick thrashing an ego twist to see what it can do with a double wrap of 32 .comge kanthal, my atty to aligator clip attachment and this little tester.. this is all with the twist cranked up to it max. use the current resistance to compare with your atty to get an idea of max wattage obtainable, interesting it can still get 10W into 1.3 ohms no wire .. Linear Device Detected Vave = 4.863 V Open Circuit Linear Device Detected Vave = 4.483 V I = 2.294 A Power = 10.284 W Current Resistance = 1.954 ohm Atty Resistance = 1.754 ohm Linear Device Detected Vave = 4.832 V I = 0.895 A Power = 4.324 W Current Resistance = 5.398 ohm Atty Resistance = 5.198 ohm inear Device Detected Vave = 4.816 V I = 1.250 A Power = 6.020 W Current Resistance = 3.852 ohm Atty Resistance = 3.652 ohm Linear Device Detected Vave = 4.794 V I = 1.565 A Power = 7.502 W Current Resistance = 3.063 ohm Atty Resistance = 2.863 ohm Linear Device Detected Vave = 4.810 V I = 1.756 A Power = 8.446 W Current Resistance = 2.739 ohm Atty Resistance = 2.539 ohm Linear Device Detected Vave = 4.852 V I = 2.170 A Power = 10.528 W Current Resistance = 2.235 ohm Atty Resistance = 2.035 ohm Linear Device Detected Vave = 4.562 V I = 2.245 A Power = 10.241 W Current Resistance = 2.032 ohm Atty Resistance = 1.832 ohm Linear Device Detected Vave = 4.094 V I = 2.442 A Power = 9.997 W Current Resistance = 1.676 ohm Atty Resistance = 1.476 ohm Linear Device Detected Vave = 3.712 V I = 2.543 A Power = 9.439 W Current Resistance = 1.459 ohm Atty Resistance = 1.259 ohm Linear Device Detected Vave = 3.682 V I = 2.728 A Power = 10.044 W Current Resistance = 1.349 ohm Atty Resistance = 1.149 ohm
Lots of good technical data. Can sorta understand it. Was this done on a single coil or dual coil? Read double wrap so i am guessing it's a single? Nice data and impressed it can push out 10W. Wonder how long it can keep that up for? Now to see what it can do with a LR dual coil. Watched Pete's video and data showed it was limited to 3.7v on an ego dual mega carto. Shame as the set up looks great and it would save me pocketing a rocket ship lol. Found duals need to run a lot higher for what I need but it should do my mates who were happy with a kr808 battery and the std 808 cartos which usually read about 2.8ohm. Test the dual coils if can you next. Will be interesting to confirm Pete's findings.