AMCI NR60E2, User Manual

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NR60 S
PECIFICATIONS
NR60E2 User Manual
ADVANCED MICRO CONTROLS INC.
18
Programmable Parameters (continued)
Total Measurement Range (continued)
Roll Over on Fractional Number of Turns (continued)
Figure R1.7 Fractional Turn Example 2
Figure R1.7 shows a single turn NR60E2 where the value of the Total Measurement Range parameter does
not divide the full range of travel into equal parts. In this case, the position value will roll over to zero after
225 degrees of rotation. In this example the value of {Total Counts Available ÷
Total Measurement Range }
is a real number, 1.6, instead of an integer.
When the {Total Counts Available ÷ Total Measurement Range } quotient is a real number, the

NR60E2 will power up with the correct position value as long as the shaft is rotated less than
half of the complete span of the encoder while power was removed. In practical terms:

For 30-bit NR60E2 multi-turn encoders:
If you remove power from the sensor and rotate the shaft less
than 8,192 turns from the point where you removed power, the position reading will be correct when
you re-apply power.

For 28-bit NR60E2 multi-turn encoders:
If you remove power from the sensor and rotate the shaft less
than 2,048 turns from the point where you removed power, the position reading will be correct when
you re-apply power.

For 16-bit NR60E2 single turn encoders:
If you remove power from the sensor and rotate the shaft less
than 180 degrees from the point where you removed power, the position reading will be correct when
you re-apply power.
If the point that you re-apply power at is greater than the limits listed above, the position value
from the NR60E2 will be off by at least ±1 turn.
Encoding Additional Turns
When the Scaling Function Control parameter enables the Counts Per Turn and Total Measurement Range
parameters, and the Counts Per Turn parameter is set to a value less than its maximum, the Total Measure-
ment Range parameter can be used to require additional rotations of the shaft before the position value
reaches the roll over count. For example, assume a single turn NR60E2 that has its Counts Per Turn parame-
ter set to 360 and its Total Measurement Range parameter set to 64,800. With this setup, the shaft of the
NR60E2 must rotate 180 turns, {64,800 ÷ 360}, before the position returns to zero. In this application, the
single turn NR60E2 acts as a 180 turn encoder with one degree position resolution.
The same trade off between resolution and number of turns encoded can be made with the multi-turn

NR60E2 encoders. For example, if a 30-bit NR60E2 encoder has its Counts Per Turn parameter set to 360
and its Total Measurement Range parameter set to its maximum of 1,073,741,824, the NR60E2 will encode
2,982,616.17 turns with one degree resolution.
In all of these applications, the NR60E2 has the same motion restrictions listed in the Roll Over on Frac-
tional Number of Turns section above. Exceeding these limits will result in a position value error of at least
±1 turn when power is re-applied.
One Rotation of a Single Turn NR60E2
Counts Per Turn = 36,000 Counts
0
0 0 0 0
Total Measurement Range = 22,500 Counts
NR60 outputs one cycle of counts from 0 to 22,499 for every 225 degrees of rotation.