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I was thinking about something similar but wasn’t sure how it could be implemented. The first way you ensure that a circuit is accurate and reliable is to ensure that all components are operating well within their ratings. If a device is “only capable of supplying 10 mA” then it should be operated at 5 mA, or even 2 mA.
Put that in parallel with a 510R reference resistor and it will change that. If put across the resistor to test it will affect the circuit non-linearly. Firstly, by putting any device (e.g. current limiter) in series with the voltage Reference, you appear to have largely eliminated it’s function of being an accurate Reference voltage ! Also, the mantra for achieving high reliability is generally to KISS .
In our own case, that’s why we built Robox so that people can start printing in just a few clicks. Despite the challenges facing the adults in the classroom, in fact most children are now computer-literate enough to understand the fundamentals of computer aided design . Has anyone got a source for pre-made 8-pin molex connectors with a decent length pigtail? I’ve seen the ones posted for the 6-pin, but not the 8-pin molex kk.
Bits 31 & 30 are essentially STATUS bits and bit5 to bit0 are sub LSB’s that are ultimately insignificant noise. Not that I have finished looking around just yet, but the ADS1114 could be sufficiently suitable and offers which equates to steps, 187.5uV/step if using the 6.144v FSR or 125uV/step with a 4.096v FSR. For absolute surety, a couple ‘crowbars’ implemented in parallel will see the earth open up and swallow me whole before component failure poses any problem.
It might be easier to determine the R from a lookup table rather than a reverse calculation, though that view might be because I’m struggling with the maths. I’m with AllyCat; putting the resistor under test at the bottom and using FVR for Vref+ you should be able to get down to +/- 0.5 ohm. Another method, depending on which PICAXE you are using, is to set the bottom of the ADC range to a different value than 0v. If you make R2 significantly smaller, say 51ohm, then the range is 0.7v to 5v. The linearization table or voltage curve is not used when you select K-Type as the input. Failure to heed this warning may result in death or serious injury to yourself and/or others.
The resolve appears to be cleverly written by the proven master of math around these parts, AllyCat and can be viewed in the code of post #1 here in this thread. I altered the values https://cryptolisting.org/ denoted by Symbol NUMERATOR and Symbol DIVISOR and Alan’s code did return the value I had hoped. I recall the effective resistance of the ADC input is said to be about 36K.
The underlined component being the 24-bit conversion result I need to work with. Here’s some code to try for the cheap version you could use it at 3v and a precision resistor not really required just enter the value… Here’s some code to try for the cheap version you could use it at 3v and a precision resistor not really required just enter the value. For the beneficial purpose of this supreme forum, once I have achieved the goal, I will post the circuit along with the PICAXE code allowing it to be repeatable by any interested parties. The ADC is undoubtedly a high impedance input, as such for example a 1K resistor could be placed between the ADC input and sense point with a negligible effect to the signal.
My problem is that my watermeter, gasmeter end government-installed electricity fusebox are in one place, and from there I got a thick XVB cable to my personal fuse box at another location. I’ll make sure i take a better photo of which screw terminals ended up being 13 and 15 when i get home tonight. It will also give me a chance to hook up my single phase saitama inu chart solar meter in the same way and hopefully my Flukso graph will populate with another line. Had meters installed this morning so I will take a few photos and hook up the pulse outputs to the Fluxso when I get home tonight. I went with the equivalent for my single phase meter. As with most issues that take a while to fix, it was a combination problem.
This is true, however in this case is resolved by taking feedback from the output side of the current limiter in turn creating an offset to compensate any error. I don’t know exactly what you are doing but it sounds on par with measuring the resistance of a detonator coil inside a brick of C-4, something medical related, something with massive adverse consequences when it goes wrong. The responses are greatly appreciated and I am eternally grateful for the loan of your brain’s. I am still of the view that charging up a capacitor and timing how long that takes may be a better way to increase resolution and accuracy.
I seem to get about half of my bed to probe before one of the connectors wiggles loose, causing the effector to crash into the bed until the belt skips. Usually this happens a few times, and then the 6-blink pattern shows up once on the LED. At this stage I feel totally lost trying to programmatically extract the conversion result and then turn it into the desired figures to display on the LCD.
If the RS one isn’t a perfect match but fits, you can always change the set of them. I have the single supply psu, will check size and see what I have later today. LandyZone is the biggest Land Rover forum on the net. We have plenty of very knowledgable members so if you have any questions about your Land Rover or just want to connect with other Landy owners, you’re in the right place.
I am very confident this setup is mathematically more than capable of achieving 0.1 ohm resolution and coupled with my appropriate reference circuit is demonstrating stable accuracy. Bottom line is that in this case error/failure stands to potentially put me to substantial expense and this is why I personally oversee and orchestrate designs and operations myself thus placing the onus solely on me. So I am confident and have the desire and mindset to just get things right upfront. Achieving 0.1 ohm resolution when measuring a one ohm resistor is relatively easy. But getting 0.1 ohm resolution of a 300 ohm resistor will be difficult, even with a 12 bit ADC.
It may not display this or other websites correctly. RS components has all manner of pre crimped cables of various lengths. Only users with topic management privileges can see it.
Ensure that the “5 volts” can NEVER significantly exceed that voltage, for example by adding a “crowbar” circuit, in its simplest form a shunt regulator such as a zener diode. Many years ago I was told that the construction of zener diodes is such that they “always fail safe” (in the context of protecting against over-voltage) to a short circuit. I don’t know if that’s still true – anything containing bond wires can “fuse” to an open circuit . Typically then repeated with a second, Reference, resistor so the stability of the capacitor is irrelevant, it’s just the ratio of two resistances / counts. Unless something is done to adjust how the ADC is converting, the readings from READADC10 won’t be sufficiently different to be able to determine the R1 better than to +/- 1 ohm resolution.
Not really his fault as this was a totally new type of job for him. I think the source of the issue might be that I’m using solid core Cat 6 cable, which is a bit stiff, and seems to exert some torque on the connector. You can have a modern full HD software compatible Atari laptop! I’ve been looking for a raspberry pi powered laptop for a long time and finally this is a reasonably priced unit. There are already tools online available to help teachers to take the first steps into designing on a 3D printer, such as TinkerCAD .
From your post, it seems you have a flat linearization for the K-Type sensors, correct? If not, please make sure to set the EGT sensor linearizations to “0” throughout. Vintage Test Gear and Workshop Equipment For discussions about vintage test gear and workshop equipment such as coil winders. There is a huge opportunity for 3D printing to offer teachers a new way to engage any and every student, no matter what their own challenges or their ages are. That’s why we’ve partnered with Kitronik to bring 3D printers to 5,000 classrooms in the UK. I believe that 3D printers should be usable by kids of all ages so that pupils have the opportunity to learn and realise their creative potential.
