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12. QUADRATURE SIGNAL CONDITIONER
Our quadrature signal conditioner board can be used for quadrature position (with Basic or
Extended main board) or for quadrature rate (with Extended main board). Two quadrature
signals, which are 90º out of phase, are applied to the Channel A and B inputs. Their phase
relationship determines whether the count is up (+) or down (-). A zero index signal may be
applied to Channel Z as a position reference.
Position in engineering units
is determined by adding or subtracting transitions, as deter-
mined by the signal phase relationship, applying a programmable scale factor to the total,
and adding programmable OFFSET1 to the scaled total. The display update rate is set by a
gate time, which is programmed to 10 ms. When the scaled total reaches a programmable
Preset, it is reset to OFFSET1.
Rate in engineering units
is determined by measuring Rate A and Rate B in transitions per
second for Channels A and B, subtracting Rate B from Rate A, and applying a scale factor.
Rate is measured over a gate time, which is programmable from 10 ms to 199.99 sec. Since
one of the two channels may not be measuring any pulses over the gate time, a timeout
from 10 ms to 199.99 sec is also programmable. The meter update rate will never be less
than every timeout. Quadrature rate provides a high resolution, high accuracy display.
A zero index function
is available on a separate zero index channel to reset the count to
the expected count when a zero index pulse is detected. For example, if 3000 counts is
expected after three 1000-count revolutions but the current count is 2998 when the zero
index pulse is detected, the count is reset to 3000. Since a wide zero index pulse could
cause a count discrepancy in the region between transitions, the zero index pulse can be
shaped by an AND combination with the A or B channels, as set by jumpers. Please see the
diagram at the top of this page, which shows an AND combination of the zero index
channel, Channel A and Channel B.
To zero the counts at a hard stop, use function reset.
Please see further manual pages for the following features: relay output, analog output,
serial communications, and transducer excitation output.
Summary of Contents for 800 plus
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