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  1. Sadlercomfort

    Mechanical Counter - Debounce

    And yes the counter is electro mechanical with a coil resistance of 160 ohm
  2. Sadlercomfort

    Mechanical Counter - Debounce

    The circuit is designed to count the revolutions on a rotating disc, a magnet is fixed on the disc and as it completes a revolution it operates the reed switch.. operating the counter. I already have 5w reed switches
  3. Sadlercomfort

    Mechanical Counter - Debounce

    Thanks, I didn't think of using a pnp transistor. On the datasheet, how did you find the gain? The hfe Value changes according to the load right.
  4. Sadlercomfort

    Mechanical Counter - Debounce

    Hi Guys, I've recently designed a circuit with the help of you guys, to create a debounce circuit to operate a counter. In order to switch the counter I need to use a reed switch, so i thought maybe i can use a transistor. I need to switch the base of a BC337 transistor using the 5W reed...
  5. Sadlercomfort

    Charging Batteries using a Power Supply

    Well I guess it just extends the life of the batteries. Perhaps C/10 is the recommended charge rate. I think the maximum charge rate is ok, but not when the batteries are almost fully charged. A sophisticated charger would charge the battery fairly quickly and limit the current as the battery...
  6. Sadlercomfort

    Charging Batteries using a Power Supply

    Thanks guys :)
  7. Sadlercomfort

    Charging Batteries using a Power Supply

    I agree Alec =)
  8. Sadlercomfort

    Charging Batteries using a Power Supply

    Are you sure 15v? I'm connecting these two in series, so will be a nominal 24v across the two. I've attached the datasheet for the battery "NP7-12FR".. I have a bad habbit of forgetting to look at datasheets. It states the maximum charging current is 1.75A at 14.4V-15V. So if I charged...
  9. Sadlercomfort

    Charging Batteries using a Power Supply

    Hi Guys, Is it possible to charge two 12v, 7AH lead-acid batteries in series directly off my DC power supply? I was thinking maybe setting the current limit to about 3A and voltage to about 28-30V. Thanks, Ash
  10. Sadlercomfort

    Capacitor Sizing - To Big/Small

    Thanks Guys, This makes alot of sense. :D
  11. Sadlercomfort

    Capacitor Sizing - To Big/Small

    One: A capacitor has a low capacitance value due to age or whatever Two: A capacitor has a high capacitance due to the error of the designer Each fault will effect the circuit differently, I need to identify how and why.
  12. Sadlercomfort

    Capacitor Sizing - To Big/Small

    There's a lot on the Internet about the dielectric failure modes, however this to be more specific to material sciences. I just to know the basic effects of having a larger capacitance than required or a lower capacitance. As these are the two fault modes I'm looking into. Talking more about...
  13. Sadlercomfort

    Capacitor Sizing - To Big/Small

    Hi Guys, I need some help finding information about capacitors and sizing. I'm trying to learn about 'Failure Modes and Effects Analysis' reports, currently writing about capacitors and how under-sizing and over-sizing can effect the circuit. I'm trying to find out how the value of C1 effects...
  14. Sadlercomfort

    Mechanical Counter - Debounce

    Hi Guys, It all seems to be working nicely now. I've used a 100uF and 2.2Ohm 1W resistor in series with it. I noticed before I was testing the circuit and using two wires for the contact, I was getting sparking across the two. Now there isn't any sparks. The circuit still seems to debounce...
  15. Sadlercomfort

    Mechanical Counter - Debounce

    Thanks Chris, Will try it out Monday, I might use a smaller cap aswell.
  16. Sadlercomfort

    Mechanical Counter - Debounce

    Ah, sorry that's what I meant the charge time will increase. Which Is why it would be a compromise between how fast the circuit can denounce the signal and the inrush of current. Now is that lifetime when the capacitor is continually being charged? Or the total time of the discharge and...
  17. Sadlercomfort

    Mechanical Counter - Debounce

    I see.. But does this satisfy my requirements if I have an aging capacitor? Now this counter may count up to 50,000 cycles, if it doesn't last that long there's no point in using this circuit. I suppose I could put a resistor in series with the coil and capacitor to limit the current, but that...
  18. Sadlercomfort

    Mechanical Counter - Debounce

    Hi Guys, Here's an update to how I solved the problem. The solution is very simple, but i get the impression some of you might not agree with it. o_O The circuit uses a 470uF capacitor and a diode in parallel with the coil. As the contact is made the capacitor charges quickly, once the...
  19. Sadlercomfort

    Mechanical Counter - Debounce

    The butterfly contact is floating 24VDC. I can't release a picture I'm afraid because it's work related and have to get permission to release details of our contacts.
  20. Sadlercomfort

    Mechanical Counter - Debounce

    Could i use the schmitt trigger to operate the base of a transistor? Switching the 24VDC through the counter?
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