[TravisR100]

I just purchased a C3 Index Pulse Card from CNC4PC. It comes prewired with a H21A2 phototransistor. This is a slotted optical interruptor. I wanted to use a reflective object sensor. I emailed Arturo and he said to use the QRB1114. So, I got one of those. I cannnot however figure out how to wire it. The QRB1114 has an emitter, collector, anode, and cathode. The C3 board has connections labeled A, E/K, and C. I don't want to burn anything up so I didn't just try hooking it up various ways. Does anyone know for sure how it should be wired?

[TravisR100]

BTW, here is a link to the cnc4pc tech doc that shows the wiring however it directly contradicts the wiring diagram for the H21A2 shown on the fairchild semi site.

http://cnc4pc.com/Tech_Docs/C3_5_WG.pdf

Fairchild doc:
http://www.fairchildsemi.com/ds/H2%2FH21A3.pdf

[Al_The_Man]

If you want to put labels on the H21A2 1=A 2=K 4=E 3=C.
The CNC4PC show the (K) Cathode and (E) Emitter common'd up.
Al.

[TravisR100]

Al, I wired up just as you said however when I do so the indicator light on the C3 card stays lit. When using the H21A2 the indicator light on the card only comes on when the slot is blocked. So, I thought maybe the logic was simply backwards and if I tried reflective tape in front of it that when it saw it the light would go off. Nope. I also thought maybe the light from the room was affecting it. I turned the lights off, that didn't help either.

So, I dug another phototransistor out of my box. This one is an OPB700AL. I looked up the datasheet and low and behold, it's labeled with the same terminology (A, E, K, and C) as the board. That made hooking it up particularly easy. (datasheet here: http://datasheet.digchip.com/344/344-01899-0-OPB700.pdf)

Same result with this one. The light remains on constantly no matter what. Any clues?

[Al_The_Man]

When using these devices the input configuration of the BOB, in this case the C3, is useful to know how the input is conditioned, Is there a link that shows this, this is the only way to quickly diagnose what is going on?
Al.

[TravisR100]

Ha, luck. From what I read CNC4PC makes good products but the documenation is pretty bad. Here is a link to the product with the doc links below it:

http://www.cnc4pc.com/Store/osc/prod...roducts_id=129

For instance, the product page shows that the product uses an ECG3100 photo transistor when in fact it is an H21A2. Also, the C3 isn't really a BOB per se. Not in the traditional sense anyway. It's just the index pulse card.

I'm using his C23 BOB which seems to work good but again, documentation is pretty bad. One doc will tell you to specifically do something while another doc will tell you to specifically NOT do the same thing.

At any rate, I came looking for answers here since Arturo (I assume the owner of CNC4PC) isn't nearly as responsive as most of the members in this forum. It was Arturo that told me to use the QRB1114. Maybe the product link above will shed some light on it.

[Al_The_Man]

Unfortunately that link is next to useless when trying to decipher the input configuration, the PDF links at the end that mention 'Further Information' do not work.
I am used to working with interfaces that show the nature of the I/O so that at least you can evaluate if and how a particular device will work.
You may have to reverse-engineer the input to find out the exact value of the components on the BOB.
Most of these opto slot devices are pretty similar so it should be fairly flexible as to type number?
Al.

[TravisR100]

Al, I appreciate you looking into it. I didn't expect you'd find much. I guess I'll have to try to get in touch with Arturo to see if he can shed some light on the situation. I just thought there might possibly be someone else who had used this same board with a QRB1114.

[arturod]

Travis,

Here are some thoughts:

- Could it be that the sensor got damaged because it was connected wrong?
- Could it be you are probably not providing the right reflective surface? Try:
o Different lights.
o A mirror.
o A completely white surface against black mate surface.

Users are always asking for me to offer a version of that that comes provided with a reflective sensor. I have not done it because I think that there are so many factors on making this work right, that trying to give support on it will kill me. I have used it a couple of times, some with excellent results and in other cases, I had to drop it.

Please check that and let me know how it goes.

I will post this answer in the form post that you sent, as it may help others.

Arturo Duncan
http://cnc4pc.com
http://cnc4pc.com/live_help.htm

[TravisR100]

It can't be the sensor. When I ordered the QRB1114 I ordered 5 of them since they were so cheap and I figured I could use them elsewhere. I tried not only two of them but also the OPB700AL that I had.

As for the surface, I've tried a mirror, white paper, a piece of polished aluminum, reflective tape provided with a photo tach, as well as powering the LED out of another phototransistor separately and shining it at the one hooked up to the C3. As for the reflective surfaces, I've tried moving them from the surface of the QRB1114 out to an inch. The spec sheet shows the proper distance to be .150". I even tried all this with the lights out thinking that maybe it was picking up ambient light.

Again, the indicator light on the C3 card stays lit no matter what when hooked up to the QRB1114 or the OPB700AL. I thought maybe the logic was "backward" with the QRB1114 but that doesn't seem to be the case either. I cannot ever get the light to go out on the C3 card.

I also tried all this with your jumper on the C3 set to active high instead of active low.

[TravisR100]

I wanted to give some credit where credit was due here. Try as I might I was never able to get this to work with the reflective sensor. Arturo from CNC4PC took the time to not only hook up what I was trying and verify that he could get it to work he even took a video of it working and posted it for me. Again, still unable to get it to work, he offered to allow me to ship it back to him and he would ship me one pre-wired with the reflective sensor. I'd say that's "above and beyond" when it comes to customer service.

[arturod]

Travis,

Thanks for your comments. We do try…

Did you receive the parts? Did all work ok? Where you able figure out what was the issue?

Arturo Duncan
http://cncn4pc.com

[TravisR100]

I have not yet received them. I'm hoping they show up tomorrow.

[TravisR100]

While I realize there are probably not a large number of people trying to use the QRB1114 reflective transistor, this last bit of information may help you if you ever try to. The replacement unit that Arturo sent me did indeed work where the other one did not. I can say however that it is extremely picky about the surface you use to reflect from. When I first wired it up and tried it out I thought again that something was surely wrong. I was using a piece of reflective tape supplied with a handheld tachometer as a reflective surface. Believe it or not, that didn't work. Neither did metallic silver paint. No matter how much I varied the distance... nothing. I then tried it against a polished piece of aluminum and voila. Since the reflective surface needed to be on the bottom, outside edge of my spindle I couldn't very well attach a chunk of aluminum. The solution was to use some spray adhesive and aluminum foil which I smoothed out with a rubber scraper.