Encoders Output, TTL, Quadrature?

[FlightSim]

Hi,

I'm trying to find a Non-Quadrature Encoder which is TTL but am confused over if and how they relate. The supply voltage available is 12VDC. Standard for TTL I understand is 5VDC. My understanding of quadrature is that you can have signals A B Z, the phase shift providing distance and direction while Z provides index. Or instead use a digital pulse train high or low.

http://www.industrialencodersdirect.co.uk/pdf/70DS.pdf

Can the encoder linked to above still be used as a TTL non-quadrature encoder which is what I'm looking for. How do I identify is it's a quadrature or digital pulse train type?

Output Signals A + B + Z + /A + /B + //Z

O U T P U T C I R C U I T
U - 5 to 30V Universal Line
Driver, suitable for
most TTL, RS422,
Push / Pull, NPN, PNP
Applications
3 - 8 to 30V input with 5v
output signals
4 - 15 to 30V input with
12V output signals
0 - 5 - 30V Open Collector

thanks

Paul

 

[VEBill]

If you ignore the B (& /B), then the A (& /A) signal will be a simple non-quadrature 'clock' (clock as in ACP, as opposed to ARP) pulse. You lose the ability to detect direction (acceptable for many applications).

For TTL, you probably want option "3 - 8 to 30V input with 5v output signals".

Stand by for others' input...

 

[LiteYear]

Agreed. Same goes for using the B signal and ignoring the A signal. Option U would probably suit too, but you'd have to supply the unit with 5V. With option 3 you have the option of supplying the unit with 8-30V and it will still give you the 5V output you want.

 

[FlightSim]

Hi Thanks for the replies, I got some what confused thou over someone terming an encoder non quadrature, I was thinking this was some specific/special type of encoder which wasn't the case. My understanding is clearer now on how the encoders are supplied with a resolution or PPR. Then say by using the A and B signals the encoder PPR Value can be multiplied if the controller has the ability to detect rising and falling edges as well as pulses. Providing x2 and x4 Logic to multiply the encoder PPR to a higher number of pulses. So have got my 1024 PPR Encoder which gives me 4096 for my x4 ability/multiple controller.

thanks Paul

 

[controlsdude]

Just be aware that a 5V signal needs a better quality cable from the encoder to your processor. Can not lose too much of that 5V signal before it goes into the noise. I believe a high capacitance cable should be ok with your application. It matters if the device is far away from your processor, the losses add up quick.

 

[FlightSim]

The board's supplying 12V for the encoder port so sticking with an encoder that has a suitable input range to accept this and this helps avoid the problem you mention about increased noise due to the lower voltage and also avoids the need to use a DC-DC voltage converter to provide 5V from the 12V available from this particular board. The cable's fairly short at about 4m as the encoder is to be used as a wheel speed odometer externally mounted on a vehicle wheel via bracket to the wheel nuts and a rod mounted to the encoder housing to prevent it turning with the wheel. thanks Paul

 

[zappedagain]

Non-quadrature encoders will put out Step (one cycle per encoder resolution) and Direction (high or low to indicate direction) signals. You typically will only use one of these within a machine. Quadrature encoders (especially RS-422) are much better for transmitting on long cables.

Z