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The solenoid will control line pressure for a lockup torque converter (automotive use) from what I understand about the noid 80% duty cycle is 262.5hz. I'm not sure how much it draws. Is there a way I can check it?
I don't think it has to be 262.5 exactly but close should be good.
Sorry don't know a lot about electronics but I can turn a wrench.
I don't think it has to be 262.5 exactly but close should be good.
Sorry don't know a lot about electronics but I can turn a wrench.
specifying 262.5kHz for the frequency required is like specifying a speed limit of 45.73 miles per hour. It's a level of precision that is unlikely to be required, useful, or achieved.
If you can get 260kHz +/- 5 kHz, then it's probably OK.
As for the current -- I'd expect it to be quite large. First check the fuses. Assume the normal current is probably half or less of the fuse rating. Or find the specs on the device...
If you can get 260kHz +/- 5 kHz, then it's probably OK.
As for the current -- I'd expect it to be quite large. First check the fuses. Assume the normal current is probably half or less of the fuse rating. Or find the specs on the device...
The 555 will handle 0.1A, but not 1.1A (There are different versions available, but the common bipolar one can drive approx 200mA.)
I'd probably use the 555 to switch a transistor or a mosfet though. And you would need to have a diode to prevent the inductive kick from the solenoid doing damage to your circuit.
I'd probably use the 555 to switch a transistor or a mosfet though. And you would need to have a diode to prevent the inductive kick from the solenoid doing damage to your circuit.
The lockup solenoids of the '80's drew 500mA and did not require any pwm. The PWM controlling the carburetor mixture control solenoid was running at 10Hz.
Is this a newer model, and could the pwm possibly be used just for a continuous circuit check by the ECM? Do you need this check function? What tranny is it?
Is this a newer model, and could the pwm possibly be used just for a continuous circuit check by the ECM? Do you need this check function? What tranny is it?
"...from what I understand about the noid 80% duty cycle is 262.5hz..."
Duty cycle and frequency aren't related as such, are they?
I mean, I can drive a solenoid at 80% duty cycle at 10kHz if I wanted to. Why do they want you to run it at that specific frequency? Does it dictate exactly how far the solenoid actuator moves?
Duty cycle and frequency aren't related as such, are they?
I mean, I can drive a solenoid at 80% duty cycle at 10kHz if I wanted to. Why do they want you to run it at that specific frequency? Does it dictate exactly how far the solenoid actuator moves?
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All I can imagine is that pure DC is used for a fast/powerful pull in, then the power is backed off to 80% to prevent overheating.
If it always operates at 80%, then my question to the manufacturer would be: "Why did you go to the extra expense and trouble of doing it this way when you could more easily have had a suitable 12V part designed and manufactured?"
If it always operates at 80%, then my question to the manufacturer would be: "Why did you go to the extra expense and trouble of doing it this way when you could more easily have had a suitable 12V part designed and manufactured?"
The transmission is 2003 model 4l80e with a manual valve body(doesn't need a computer to run) and the only noid in it is for the lock up function.
I don't think the frequency dictates noid travel. Just its on off rate witch in turn controls line pressure.
And I don't think the dogs will be able to hear the noid hum because of the. Four inch exhaust. Lol
Thanks everyone for the replies
I don't think the frequency dictates noid travel. Just its on off rate witch in turn controls line pressure.
And I don't think the dogs will be able to hear the noid hum because of the. Four inch exhaust. Lol
Thanks everyone for the replies
A pwm was used to achieve a soft lock. If it was a non-pwm it would be a hard lock a would damage parts inside of the transmission
Yes you can use a 555 for PWM.
Go here:
http://home.cogeco.ca/~rpaisley4/LM555.html
Scroll down until you see the "LM555 - ASTABLE OSCILLATOR CALCULATOR"
Enter 5 ohms in the R1 & R2 fields then enter 360 mF in the C1 field. Now click CALCULATE and you see that this combination will generate a square wave of 267.22 hz at a 66% duty cycle.
Since a 555 can only drive a 200 ma load, you'll have to take the output from pin 3 and connect it to the gate of an N-CHANNEL MOSFET and let that drive the solenoid.
I just made a fuel injector tester from two 555s and an N-Channnel MOSFET:
http://www.dinofab.com/fuel_injector_tester.html
It works great.
The 555 is a very versatile chip.
Hope this helps.
Go here:
http://home.cogeco.ca/~rpaisley4/LM555.html
Scroll down until you see the "LM555 - ASTABLE OSCILLATOR CALCULATOR"
Enter 5 ohms in the R1 & R2 fields then enter 360 mF in the C1 field. Now click CALCULATE and you see that this combination will generate a square wave of 267.22 hz at a 66% duty cycle.
Since a 555 can only drive a 200 ma load, you'll have to take the output from pin 3 and connect it to the gate of an N-CHANNEL MOSFET and let that drive the solenoid.
I just made a fuel injector tester from two 555s and an N-Channnel MOSFET:
http://www.dinofab.com/fuel_injector_tester.html
It works great.
The 555 is a very versatile chip.
Hope this helps.
5 ohms for those resistors is way too low, and 360uF (makerdino didn't mean mF -- he may have been mislead by the obsolete abbreviation mfd) is not a common value capacitor. And the durty cycle is not what you want.
try 8k2, 2k5, and 0.47uF
The frequency is 225Hz, and the duty cycle close to 80%
For a frequency closer to what you want, two 0.82uF capacitors in series (giving 0.41uF) will give you a frequency of around 260Hz.
The actual frequency will be most influenced by the capacitor which will (if you're lucky) have a tolerance of 10%
try 8k2, 2k5, and 0.47uF
The frequency is 225Hz, and the duty cycle close to 80%
For a frequency closer to what you want, two 0.82uF capacitors in series (giving 0.41uF) will give you a frequency of around 260Hz.
The actual frequency will be most influenced by the capacitor which will (if you're lucky) have a tolerance of 10%
Is the duty cycle real important? I mean is 260hz @60% the sameas 260hz@80%? Also a messed around a little today with a calculator. And the best I came up with was 262.41hz@ 66% using 4700ohms for r1 and r2. .39uf(390nf?) For c1
I'm not sure( obviously ) how everything works together
Also Steve does 8k2=8002?
Thanks.
I'm not sure( obviously ) how everything works together
Also Steve does 8k2=8002?
Thanks.
The duty cycle will be far more important than the frequency. Get the duty cycle right first, then play about to get the frequency close.
80% duty cycle results in an average voltage of 0.8 x 12 reaching the solenoid. 60% results in 0.6 x 12 volts average. Is a difference of 25% important? I'd bet it would be.
80% duty cycle results in an average voltage of 0.8 x 12 reaching the solenoid. 60% results in 0.6 x 12 volts average. Is a difference of 25% important? I'd bet it would be.
Remember that the components have tolerances.
if you use 1% resistors and 10% capacitors, then the duty cycle could differ by up to 2% and the frequency by 12% -- in all likelihood the actual difference will be much lower.
8k2 = 8200. The multiplier is used in place of the decimal point. Similarly 2R2 would be 2.2 ohms. For some reason I've never seen this used with capacitors. So 1p2 or u39 are not things you'll see. (I'm pretty sure I've never seen this...)
if you use 1% resistors and 10% capacitors, then the duty cycle could differ by up to 2% and the frequency by 12% -- in all likelihood the actual difference will be much lower.
8k2 = 8200. The multiplier is used in place of the decimal point. Similarly 2R2 would be 2.2 ohms. For some reason I've never seen this used with capacitors. So 1p2 or u39 are not things you'll see. (I'm pretty sure I've never seen this...)
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