I described using the transformer in reverse, as a step up. 6 volts to 240v.If the motor already runs directly off 240VAC then it would have very high impedance. Reducing the voltage will not work.
Ok, I now catch your idea. It's worth trying.I described using the transformer in reverse, as a step up. 6 volts to 240v.
Ok, I now catch your idea. It's worth trying.
Think I can get the parts at the local Microcenter store, along with some cranial support? Remember, my experience in this field stops just after "gee, you mean a wire wrapped around a nail and hooked to a battery will make a magnet!? Cool..."Ok, here is my solution.
Take the 60Hz AC LINE signal through an opto-isolator to a microcontroller (MCU).
Program the MCU to generate 50Hz. Quartz crystal stability is not required.
At every 6 cycles of 60Hz detected, re-sync the 50Hz oscillator.
Feed the 50Hz output to a step up transformer or similar.
I can do this with a small 8-pin MCU chip.
Oh, by the way, the wire of the coil appears about as thick as a human hair....Think I can get the parts at the local Microcenter store, along with some cranial support? Remember, my experience in this field stops just after "gee, you mean a wire wrapped around a nail and hooked to a battery will make a magnet!? Cool..."
Ok, here is my solution.
Take the 60Hz AC LINE signal through an opto-isolator to a microcontroller (MCU).
Program the MCU to generate 50Hz. Quartz crystal stability is not required.
At every 6 cycles of 60Hz detected, re-sync the 50Hz oscillator.
Feed the 50Hz output to a step up transformer or similar.
I can do this with a small 8-pin MCU chip.
I like the idea, but I still think using a crystal reference for the MCU would be better. The whole circuit could run from a DC wall wort or even batteries. I would still like to know what current it draws from the 60Hz supply.Ok, here is my solution.
Take the 60Hz AC LINE signal through an opto-isolator to a microcontroller (MCU).
Program the MCU to generate 50Hz. Quartz crystal stability is not required.
At every 6 cycles of 60Hz detected, re-sync the 50Hz oscillator.
Feed the 50Hz output to a step up transformer or similar.
I can do this with a small 8-pin MCU chip.
Not necessarily. Mains 60 Hz is very stable as required by law. Power companies have complex circuits to maintain line frequency at an average of 60Hz. You’d need similar circuitry to adjust a Crystal reference over time.I like the idea, but I still think using a crystal reference for the MCU would be better. The whole circuit could run from a DC wall wort or even batteries. I would still like to know what current it draws from the 60Hz supply.
I agree with you on accuracy but it requires a connection to AC mains, my solution could run from a DC supply. Some crystal references are temperature compensated, I have used a DS3231 RTC with an Arduino and it is good to less than two minutes a year. Your design is probably more accurate but I was thinking of avoiding a connection to mains voltages.Not necessarily. Mains 60 Hz is very stable as required by law. Power companies have complex circuits to maintain line frequency at an average of 60Hz. You’d need similar circuitry to adjust a Crystal reference over time.
By using the stable 60Hz frequency as a reference and adjusting your 50Hz output every 0.1s, you’ll get a very very stable output. You’ll have corrected the frequency 600 times a minute. The adjustment is done in software and can account for several variables. Such as MCU clock, instruction times, temperature variations, load variations, et.al.
Check out Romanblack.com for some algorithms.
Unfortunately, I wouldn't know how to test for the lowest voltage. Also, as the motor requires a physical "kick start", often several attempts, I wouldn't know if it wasn't running because the voltage was too low, or if it needed just one more kick to make it start. A circuit drawing would be great...a friend of mine might be able to help me through it. I'm looking for the KISS principle here...plug and play. I apologize if I'm being annoying...I'm really in the dark here, and you folks have given me the best hope so far of getting this fixed.You can use a crystal on the MCU instead of AC LINE frequency if you wish but the time-keeping ability will not be as good. I can put together a circuit for you if you wish but you will have to do some assembly.
We suspect that the coil takes very little current. More importantly we would like to know what is the lowest voltage at which the clock will still run.
Oh, sure... change the requirements. Considering you want to avoid a mains connection, I like your use of a RTC along with the Arduino.I agree with you on accuracy but it requires a connection to AC mains, my solution could run from a DC supply. Some crystal references are temperature compensated, I have used a DS3231 RTC with an Arduino and it is good to less than two minutes a year. Your design is probably more accurate but I was thinking of avoiding a connection to mains voltages.
Do you have a way of programming any MCU if I send you the file?Unfortunately, I wouldn't know how to test for the lowest voltage. Also, as the motor requires a physical "kick start", often several attempts, I wouldn't know if it wasn't running because the voltage was too low, or if it needed just one more kick to make it start. A circuit drawing would be great...a friend of mine might be able to help me through it. I'm looking for the KISS principle here...plug and play. I apologize if I'm being annoying...I'm really in the dark here, and you folks have given me the best hope so far of getting this fixed.
I have no way of programming the MCU. How much would you want for the circuit board / chip? Also, if it's a simple case of "solder the hot wires directly from the outlet here, solder the motor wires there" I can handle it.Do you have a way of programming any MCU if I send you the file?
Otherwise I can send you a chip or the chip already mounted on a circuit board.
I have the early version that can be started in either direction. It definitely does NOT start on it's ownThis is a quote from wikipedia, maybe this is what you have, or it could be because you are running it from 110v when it was designed for 240v. (see Wikipedia: ELECTRIC CLOCK )
Spin-start clocks[edit]
The earliest synchronous clocks from the 1930s were not self-starting, and had to be started by spinning a starter knob on the back.[9] A flaw in the design of these spin-start clocks was that the motor could be started in either direction, so if the starter knob was spun the wrong way the clock would run backwards, the hands turning counterclockwise. Later manual-start clocks had ratchets or other linkages which prevented backwards starting. The invention of the shaded-pole motor allowed self-starting clocks to be made, but since the clock would restart after a power interruption, the loss of time would not be indicated.
by Duane Benson
by Aaron Carman
by Aaron Carman
by Duane Benson