Dear anyone

Please help me, who can give me a RPM-Meter digital or manual schematic diagram?
Please i need it

Thank"s

 

Here is one example:

Ante :roll:

Attached Thumbnails

 

 

Is there a Printed circuit layout for this somewhere?

What does Unterbrecher mean?

Thanks, B&M

__________________
B&M

 

I couldn’t find any pcb for it, sorry. Unterbrecher means Circuit breaker according to Babel fish but I think they mean “points”.

Ante :roll:

 

direct translation would be 'disconnector'. It is the input for a reed switch wich gets closed every time the wheel (of wich you want an RPM count) does 1 rotation.

It's commonly used, a small magnet on the wheel and a reed switch, every time the magnet comes in front of the reed switch it closes, so you can count rotations.

 

Exo,

I think they mean the points in the distributor, which are very rare these days. Most cars have electronic ignition and no more breaker points. I can see there is a possibility to select 4, 6 or 8 cylinder engines on the CD4018 pin 1, 11, 6 and 4. You can adapt the input to most any source of pulse and the decade to in the interval needed. A phototransistor and a piece of reflective tape will probably work. Maybe just remove the CD4046 and the CD4018 then let the pulse go directly to the clock (pin11) on the 74C925? These two ICs are there just to compensate for the way a four-stroke engine works and with different number of cylinders I think. What do you think?

Ante :roll:

 

I dunno the application of this circuit, and that schematic that was given is definitly for a car, so I'm just gonna assume it's for a car.

IMO, it would be too hard to get it the diode positioned.
What you need is to find a way to sense when a spark plug fires. I'm not sure how the sensor work exactly, but my friend has a digital tach on his go-kart and the lead just cable tied onto the plug wire.
I also had an anlog tach for my 86 Chevy Celebrity, the sensor for that connected to the untransformed end of the coil (it had a distributor). the tach also had a switch for 4,6,8 cylinders.

If it's for a car without a distributer, all you have to do is sense when the #1 cylinder fires and multiply by 4 (4 revolutions per cycle).

I'd suggest trying to find a different schematic...

__________________
Jeff
To the optimist, the glass is half full.
To the pessimist, the glass is half empty.
To the engineer, the glass is twice as big as it needs to be.

 

Hi all,

I want to make a rpm meter for my metal lathe.Could I use a proximaty switch for an input. I have a prox swithch that will give an output of 10-30vdc. Maybe I can hook it to a hi-speed solid state relay to close for every rotation of the lathe spindle? 0-4000 rpm. :?:

Any Ideas?

Thanks

__________________
B&M

 

A microcontroller with an LCD display would be far, far simpler.

Depends on what you mean by proximity switch. As far as a common magnetic reed switch, probably not, it's slow and probably not rated for millions of cycles. Now a Hall effect sensor would do just fine. That's what gets used for most RPM sensing, and they're dirt cheap. Also you could make an optical sensor, but don't get sawdust on the sensor.

I do not see why you need a solid state relay at all. The sensor's ground will be tied to the rest of the circuit ground so you need no isolation. The relay is too slow to use for signal isolation (also far too large and expensive!)- you'd just use a cheap optoisolator which comes in a DIP pkg.

 

Yeah,

I have some Hall Effect sensors and some SSR's but a opto isolator is a very good idea. It would fit on a PCB a lot better :lol: .

As far as a microcontroller, That would require a programmer which would be a whole project in itself. Plus I am not well versed in them at this time.

Thanks for the input guy's.

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B&M