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super-d
02-23-2008, 07:00 PM
I have a flow meter that operates on 4 to 24 volts (I'm using 5 volts) and generates 1120 pulses per liter. I'm just about to order an 8/8/8 and a few other items but was wondering if there is a way to do this with the 8/8/8 with either a Phidget sensor of some type (I didn't see one) or some other device.

Thanks in advance
David

Alex
02-24-2008, 03:42 PM
Nope. Phidgets doesn't make any flow sensors. They do have a pressure sensor, but that's for gas, not liquid. As far as other sensors that you can use with the 8/8/8, so long as it is a standard 5vdc analog sensor, then you can use it with the 8/8/8. I haven't really looked around to see if these exist.

What sort of project are you working on?

super-d
02-25-2008, 10:06 AM
Alex,

I think you may have misunderstood my question :). I already have the flow meters but I'm just looking for a way to count the pulses they generate. I left a message on Phidgets and they say that is one of the things they are planning on but haven't gotten that far yet.

I'm just looking for some additional hardware I could interface to do the job in the mean time. Was also wondering since I have a pulse which will be low going to high (5v), if I could just use one of the digital IO ports and count how many times it goes high using an event for that pin.

David


Nope. Phidgets doesn't make any flow sensors. They do have a pressure sensor, but that's for gas, not liquid. As far as other sensors that you can use with the 8/8/8, so long as it is a standard 5vdc analog sensor, then you can use it with the 8/8/8. I haven't really looked around to see if these exist.

What sort of project are you working on?

Alex
03-05-2008, 02:50 PM
did you get any reply from Phidgets yet? This is a bit over my head, but I'm curious what they say about it...

super-d
03-06-2008, 06:02 AM
Alex,

Sorry about that. Yes I did get a reply. They don't have anything but have something in the works.

David

Adrenalynn
05-15-2008, 01:31 PM
This is old, again, I'm just trying to go through some of the really interesting old stuff...

If you have a 0vDC/5vDC strobing output, why couldn't you simply count pulses on an analog input?

I just set a relay on a 5vDC regulated supply, and used the Make Controller to cycle the relay once a second, and an analog input to log to a variable anything over a 4v change, +/-. The Make Controller was able to both cycle the relay and count the cycles from the relay simultaneously. I hooked-up my digital scope and logged the pulses at the same time to the datalogger, and the numbers matched identically over 3 mins.

It's going to depend also on volume/sec and how fast your microcontroller or bus interface is. If you're moving a hundred litres/sec, your microprocessor may not be able to generate interrupts fast enough. Something to consider.