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  1. C

    Automation coding to mimic Ladder Logic

    Interesting debounce method. I think the following line is wrong: if (FS=0){digitalWrite (footswitchD,LOW);} because footswitchD is a boolean variable, not an I/O pin. I believe it should be: if (FS=0){footswitchD = false;} // true & false should be globally defined as part of the...
  2. C

    Automation coding to mimic Ladder Logic

    Hardware wise, can I suggest you isolate the physical switches from the CPU pins. A transistor, an opto, all the way up to the plugin Opto-22 modules. Software wise, you need to debounce those switch inputs. The quick & dirty solution is probably just a great big delay at the end of the loop...
  3. C

    Cell-Log Mod - Perfectly even drain! - FINISHED!

    Heath, I have another question. Is there any reason why the HVC+ signal from the opto's doesn't connect directly to the gate of the Fet? Seems to me there are 2 transistors and a number of resistors which are redundant. Amanda
  4. C

    Cell-Log Mod - Perfectly even drain! - FINISHED!

    The biggest problem with the cell-logs is their diminutive display, especially since my eyesight isn't getting any younger. For the original target market, the RC guys, this is fine. So the BVM clone with it's slightly larger and more legible display will be a boon to us. So much so I just...
  5. C

    Cell-Log Mod - Perfectly even drain! - FINISHED!

    Heath, Looking at the schematics, I take it this is a hiccup type charge controller. That is, once a cell charges up & triggers the alarm out on the cell-log, switches off the FET in the negative charge lead, charge current stops, the full cell bleeds down slightly via the TL431, the cell-log...
  6. C

    Cell-Log Mod - Perfectly even drain! - FINISHED!

    I think you mean element 14. http://au.element14.com At least it is in Australia. Amanda
  7. C

    Cell-Log Mod - Perfectly even drain! - FINISHED!

    Quiescent current (per channel) typically 2mA. 2.8mA worst case across the full temperature range. 8 channels * 2mA = 16mA. Hours connected to drain 1AH = 1000/16 = 62.5 Hrs = 2.6 days. And it's not rail-to-rail output. Typically (V+) – 0.8 (800mV). Amanda
  8. C

    New Jersey - When is a bike not a bike?

    Here in NSW Australia, those scooters with tacked-on pedals are specifically banned. And, an electric assist push-bike must actually look like a push-bike. As someone who has commuted for the past 4 years on an EVT electric scooter, I'm afraid I have to agree with the authorities on this one...
  9. C

    Switch mode supply mod

    Mike, If you leave the thermistor circuit alone, and permanently enable the fan with the Q5 mod (switch in parallel or wire link Collector-Emitter), the over-temp protection should still work. This works by driving the DTC (dead time control) of the TL494, which decreases the pwm. Also, things...
  10. C

    Any one got a dead meanwell? I need a fan

    Neil, Got plenty of 80mm fans, and a 40mm, no 60mm. Glad the Q5 mod worked for you. Good point of doing it this way, the thermistor "stage 2" protection still works as designed. If it does overheat (because the fan failed), it drives the Dead Time Control on the TL494 to cut the current by...
  11. C

    Any one got a dead meanwell? I need a fan

    Neil, Does my memory serve me correctly, and you're in Australia? If so, Jaycar have a 60mm square x 25 mm deep, 12 volt, 130mA, 20 CFM fan for $19.95 (YX-2505). Of course, donated from junk box for cost of postage is better. If no one else pipes up, I'll look in my junk box tomorrow. You...
  12. C

    charging LiFePo4 with solar cells

    Use panels in sets of 3 in series to charge 36 volts directly. Amanda
  13. C

    charging LiFePo4 with solar cells

    RTA; There are a number of issues related to carrying panels with you. Weight Fragility Pointing them at the sun whilst travelling The sheer area of panels required to be meaningful (with attendant wind drag issues) In practice, your panel will put out significantly less than the sticker rating...
  14. C

    Q: Mtn bike front suspension, max rake?

    Thank you. Still not sure which way to jump. There's some forks coming up on eBay shortly that I may try. Still contemplating whether to build a springer or not. Gotta start putting all my thoughts down on paper. Amanda.
  15. C

    Q: Mtn bike front suspension, max rake?

    Just toying with some design ideas here. How far over can I lean mountain bike front suspension forks before they bind up and stop working. Thinking full suspension chopper/dragster thingy. Obviously, we're talking budget forks, not top $helf. Amanda
  16. C

    Chopper with Cyclone kit

    Time for an update & some fresh piccies. The batteries are now 8s * 20AHr Foxx prismatics which cost me $300.00. And you can't put the motor on top, because the idler will be under tension, and it will bend the shaft. Peak current to the Cyclone 180 watt motor is 30 amps. The...
  17. C

    Reviviing LiFeP04 battery

    PM sent.
  18. C

    Reviviing LiFeP04 battery

    Partially recharging using a laboratory, or benchtop, power supply would be quite easy. These are the ones with variable voltage & current limit. Typically 0-30 volts & 0-3 amps. A jury-rigged setup could be fashioned using any sort of dc power supply and a resistor. You can access single or...
  19. C

    What exactly do I need to leave a pack charging unattended?

    I think you've got that backwards. The ones that fall back quickly are the ones to be suspicious of. A good cell will hold its surface charge for a good long while.
  20. C

    What exactly do I need to leave a pack charging unattended?

    Indubitably, I went back to the site of your bms, and read the user manual carefully. They talk about a unit with shunting option, but don't give any details. The standard setup connects the charger directly to the batteries. It then switches off the charger when the first cell hits HVC. This...
  21. C

    What exactly do I need to leave a pack charging unattended?

    Njay, I guess there could be a subtle distinction there. Yes, poorly designed/implemented charging/bms can be a serious problem. It is my considered opinion that any charging solution which relies on the voltage out from the charger matching the batteries voltage is ultimately doomed to...
  22. C

    What exactly do I need to leave a pack charging unattended?

    A 40AH TS pack is not cheap. Do it right and use a BMS. And forget the Ghetto Guerrilla straight off the mains idea. Good way to kill yourself. And the rectified and filtered dc voltage is sqrt(2) times the ac rms value. So 120 volts ac is 170 volts dc. (approx). For the record, I've had a 16s...
  23. C

    Problem with meanwell power supply knock off.

    If it say's NTC1 next to it, then it is definitely a Thermistor. Temperature dependent resistor. Negative Temperature Co-efficient. Starts off high resistance which limits the inrush current. Current flowing through it causes it to warm up, which lowers the resistance.
  24. C

    Problem with meanwell power supply knock off.

    I'd hazard a guess that was a thermistor. NTC ? Used to limit the inrush current at switch on. Salvage a replacement from a dead PC power supply. Amanda
  25. C

    What exactly do I need to leave a pack charging unattended?

    The Meanwells do have a voltage adjustment pot. Adjustment range is in the pdf datasheet. And they can be hacked to take it a little higher or lower. Regen on a light-weight vehicle is generally deemed "Not Worth the Effort".
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