Curtis 1222 - Supervision: Following Error

Curtis 1222 Manual, os 15
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2 9 J A N U A R Y 2 0 1 3 D R A F T
3 — PROGRAMMABLE PARAMETERS: Supervision Parameters
SUPERVISION: FOLLOWING ERROR
ALLOWABLE
PARAMETER RANGE DESCRIPTION
Error Tolerance (deg) 1.0° – 90.0° Defines the maximum difference allowed between Steering Command (deg)
0x40BE 0x00 182 – 16380 and Wheel Position (deg). The difference can be seen in the monitor
variable Following Error (deg).
If the programmed Error Tolerance (deg) is exceeded for the
programmed Error Time while the wheel speed is less than the programmed
Speed Tolerance (deg/s), a Following Error fault is issued.
A setting of Error Tolerance (deg) = 90.0° turns off this fault check.
Speed Tolerance (deg/s) 0.0 – 180.0 This parameter defines the minimum allowed speed for the steered wheel.
0x40C0 0x00 0 – 32767 This is a second condition for the Following Error check. By checking
the velocity of the steered wheel (first derivative of Wheel Position) this
check ensures that the steered wheel is moving in the correct direction at
or above the minimum allowed speed. The wheel speed can be seen in the
monitor variable Wheel Speed (deg/s).
A setting of Speed Tolerance (deg/s) = 0.0 removes the influence of
steered wheel speed from the Following Error check.
Setting Speed Tolerance (deg/s) to a value greater than zero (thus
enabling the influence of wheel speed in the Following Error check) should
allow the Error Tolerance (deg) and Error Time parameters to be set lower
without false fault trips. Setting Error Time lower allows the Following Error
fault to be detected more quickly.
Error Time 0.1 – 10.0 s Defines how long Error Tolerance (deg) can be exceeded if the steered
0x40BF 0x00 1 – 100 wheel is not moving in the right direction with a Wheel Speed (deg/s)
equal to or greater than the Speed Tolerance (deg/s).
Since the first derivative (Wheel Speed (deg/s)) is inherently noisy,
the timer is implemented as a count-up/count-down timer (Following Error
Time Accumulated) where the fault time is set by the parameter Error
Time.
Example: If Error Tolerance (deg) = 5 and Speed Tolerance (deg/s)
= 10, the Following Error Time Accumulated will count
up when the Error
Tolerance is >5
and the Wheel Speed (deg/s) <10. Following Error Time
Accumulated will count down if either the Error Tolerance
≤ 5 or the Wheel
Speed (deg/s)
≥10.
Error Time must be set long enough for the steered wheel to reverse
direction and reach the minimum speed (Speed Tolerance (deg/s)) under
the worst case conditions.
PCF RIS
SUPERVISION MENU, cont’d
ALLOWABLE
PARAMETER RANGE DESCRIPTION
PCF RIS
Stall Timeout 0 – 2000 ms Defines the timeout time for the motor stalled fault check.
0x40DA 0x00 0 – 2000