Basic encoder tutorial?

[mattbesquare]

I am looking to wire up my encoders, these things are monsters-7x2 pinout.. Just wondering if there was a thread or site that goes over basic wiring terminology or standards? I was thinking of setting them up to atompro's, if they can handle the bandwidth 5k ppr.

[mattbesquare]

As usual, I keep reading into things after posting-

so my encoder has:

A
B
Z
A/
B/
Z/
Sensor 5V
Sensor 0v
/
(/)/(UAS/)
0V
Shield


So, if I powered up this little bad boy, and only monitored ABZ, would I only have a four position/directional encoder per 360 degrees of rotation?

A/,B/,Z/ I read somewhere that these are the middle points of the wave, so to put in simpler terms 0+45 degrees for pulses (45, 135, 225, 315 degrees)

what the heck is the "/" channel?!? though,

I and using ROD 476 encoders from heidenhain. And Al (thank you so much) was the only kind soul to give me pinout info on these (I have a bunch)...even Heidenhain didnt get back to me with info on these.

Can anyone correct me on these assumptions?

Also, I am confused why as to why these are called 5000ppr encoders...wouldn't TTL imply a required base 2 (binary) output resolution?

[Al_The_Man]

The Basic encoder pulses are A & B with Z being a one/rev marker pulse.
The /A etc pulses are complements of the main ABZ, this means that when each of the ABZ pulses occurs the /A /B /Z are of the exact opposite polarity, this is called RS422 differential TTL transmission, which is a noise reduction standard.
You can use them in the single ended mode by just using ABZ, this has no effect on the resolution at all.
If they are 5000 pulses per rev encoders, this means that the A pulse and the B pulse each have 5000 pulses/rev.
The two are shifted to 90deg apart, hence quadrature encoder, some controllers will take the natural quadrature count and multiply it by either x2 or x4 by using the leading and trailing edges of each pulse.
so yours could be used at up to 5000x4 = 20,000p/rev detection.
Al.

[mattbesquare]

Originally Posted by Al_The_Man The Basic encoder pulses are A & B with Z being a one/rev marker pulse. The /A etc pulses are complements of the main ABZ, this means that when each of the ABZ pulses occurs the /A /B /Z are of the exact opposite polarity, this is called RS422 differential TTL transmission, which is a noise reduction standard. You can use them in the single ended mode by just using ABZ, this has no effect on the resolution at all. If they are 5000 pulses per rev encoders, this means that the A pulse and the B pulse each have 5000 pulses/rev. The two are shifted to 90deg apart, hence quadrature encoder, some controllers will take the natural quadrature count and multiply it by either x2 or x4 by using the leading and trailing edges of each pulse. so yours could be used at up to 5000x4 = 20,000p/rev detection. Al.

Perfect, perfect, perfect... this is what I was looking for. I googled for like 4 hours and couldn't find out how the counts were multiplied and worked it out in my head last night trying to fall asleep. I was wrong, but this is what I needed to know.

Can you tell me what the "/" line is for that diagram? Is that something to do with phase offset? Everyone uses their own nomenclature...

[Al_The_Man]

It is a way of showing the complement or opposite, the bar should actually be horizontal line above the letter, but the easiest way with a normal keyboard is to use a "/".
Quote:
Logical complement In Boolean algebra, the logical complement or negation of a Boolean value is the opposite value, given by the following truth table: A | -A --+--- T | F F | T -A is also written as A with a bar over it or with a small vertical line hanging from the right-hand end of the "-" (LaTeX \neg) or as A'. In the C programming language, it is !A and in digital circuit design, /A. (1995-01-24). Source: The Free On-line Dictionary of Computing..

The way differential works is that at the receiving end the signals have to be 1 positive going pulse for every negative going pulse, it is reasoned that if EMI is imposed on the wiring, it is extremely unlikely that the EMI will impose both a negative signal and positive signal simultaneously on each conductor.
Al.

[mattbesquare]

So why have a line dedicated to "/" or it could be an italic L... in the diagram, pin 9 uses it alone, pin well, what should be 13 is labeled "/" and pin 9 has it because it is the shield, so it should be ground... correct?

I would get if that is what they use for ground, but then could you possibly explain to me what pin 7 means in the top table?

[Al_The_Man]

Pin 9 is shown as shield in the case the / is just meant to indicate there is no colour.
Could be a Little misleading I guess.
Al.