Delta RMC151 - Manual (Page 872)

RMC70/150 and RMCTools User Manual
edge on the Return pulse (for PWM)
after three (3) control loops.
Quadrature Not used for Quadrature.
Resolver Not used for resolvers.
SSI As specified by the SSI Overflow
Mode.
In general (see the Input Estimated status bit for details and
exceptions), the Transducer Overflow error bit is not set
until the error condition is present for three consecutive loop
times. When a Transducer Overflow error condition is first
detected, the RMC estimates the position by extrapolating
the last two positions. The Input Estimated status bit be will
be on while this occurs. After the condition is detected 3
times in a row, the Transducer Overflow error bit is set. The
Input Estimated bit is always set while the error condition is
active, even after the Transducer Overflow error bit is set
following the first 3 loop times.
8 NoiseErr Noise Error
Note:
The Noise Error bit may turn on because the Noise Error Rate
parameter is set too low. The Noise Error Rate should be set to a
value much higher than the expected velocity of the axis. If your
axis is experiencing Noise Errors, this is the first item you should
check. Setting the Noise Error Auto Stop to Status Only to avoid
halting due to an overly low Noise Error Rate parameter can
cause significant control problems.
This bit is set when the RMC detects transducer noise. The
following list indicates when this occurs for various
transducer types.
Position:
Analog, MDT, SSI,
Resolver
If the input rate of change of
the input exceeds the rate
specified by the Noise Error
Rate parameter for a period of
3 loop times, then this error bit
will be set. During noise less
than 3 loop times, the Actual
Position is estimated to allow
recovery from electrical noise,
during which time the Input
Estimated Status bit will be on.
Make sure that the Noise Error
Rate parameter is set much
higher than the expected
velocity of the system. If it is
set too low, the Actual Position
and Actual Velocity may be
incorrectly calculated,
adversely affecting control.
A Noise Error can also be
852 Delta Computer Systems, Inc.