Re: [CAD_CAM_EDM_DRO] Re: encoder steps

Hi there.

Just one nitpick:

The outputs aren't likely to be a differential pair (though they could
be used that way). I have encoders with complementary outputs, and the
signal level on each output is 0 or 5V, and is referenced to encoder
ground. If the wires are marked A+ / A- or +A / -A, then it's probably
a differential pair. If it's A / not A, then it's just two outputs for
the same thing, one active high and the other active low (this is how my
encoders work).

- Steve

vavaroutsos wrote:

>Aaron, as Tom explained the answer is yes, but this has nothing to do
>with the fact that you have 4 wires on the encoder. The A/not A and
>B/not B are differential outputs. This means the value of A or B is
>determined by comparing A to not A and B to not B. Ground is not used
>as a reference. This makes the signals more immune to noise as any
>noise will be common mode (assuming wires are twisted together) and
>cancelled by the differential comparison.
>
>~petev
>
>--- In CAD_CAM_EDM_DRO@yahoogroups.com, Aaron Bott <azzi_b@y...>
>wrote:
>
>
>>I have 250 physical step encoders on the mill I am converting. As
>>
>>
>these read by 4 channels A, not A, B, not B does this mean that there
>are effectively 1000 actual steps - ie 1 rpm = 1000 steps ?
>
>
>>
>>thanx
>>
>>Aaron
>>