rotork CVQ 1200, Инструкция по установке и обслуживанию

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Bumpless Transfer Distance (BTD)
The bumpless transfer distance is a pre defined percentage
of position error that will reduce the actuator speed to a pre-
determined speed The Default Bumpless Transfer Distance is 5%.
Bumpless Transfer Speed
The speed in % of rated maximum speed that the actuator
will revert to if the bumpless transfer distance is exceeded.
The actuator will resume normal set speed once it arrives
within the preset BTD.
The Default Bumpless Transfer Speed is 40% of rated.
Send Settings
Upload the Advanced 2 configuration changes to
the actuator.
Installation & Setup Guide
Advanced 2
Direction Change Threshold Distance
The distance the actuator must move before a direction
change is registered by the datalogger as a cycle.
This is used to prevent small dither movements from being
counted as these are considered too small to cause valve wear.
The default setting is 0.25% of overall valve travel.
Total Direction Changes Before Alarm
Can be used to generate an alarm when a set number of
direction changes has occurred.
Total Travel Before Alarm
Can be used to generate an alarm when a set distance has
been travelled by the actuator output drive shaft ft/meters.
Bumpless Transfer
On start up of the process or after manual intervention the
actuator could be required to move a long way to its setpoint.
If the actuator moved at too great a speed this could cause
a ‘bump’ or unstability in the control system loop leading to
valve overshoot and oscillation.
To reduce this effect the ‘bumpless transfer’ reduces the
actuator output speed to a lower level if the distance to travel
is more than a pre-determined value. Once the actuator
arrives within the Bumpless Transfer Distance (BTD) area it will
resume travel at its normal speed.
Fig. 44.2 Fig. 44.1