Toptech Systems MultiLoad II User Manual page 124

Chapter 4 – General Configuration
Parameter
Fallback Time
Fallback Retry Time
Fallback Retry Volume
Fallback Minimum
Pressure
Fallback Minimum
Rate
Fallback Increase Rate
Fallback Decrease
Rate
Fallback Retry Min
Pressure
Fallback Vapor
Pressure
API Table Name
API 54 YG
API Extrapolated
Range
Firmware Version 3/4.31.37
Action
If during the High Flow stage, the flow rate is below the High Flow Rate deadband for
the period specified by this parameter, the control algorithm will search for a controllable
rate. Begin with a value of 3 seconds. An entry of zero seconds will disable the Fallback
feature.
After a controllable rate has been obtained, it will be maintained for a period determined
by the setting of this parameter. Upon the expiration of the Fallback Retry Time, the
algorithm will attempt to regain the target flow rate. If the target flow rate cannot be
regained in the time allotted by the Fallback Time parameter, the algorithm will search
again for a controllable rate. Begin with a value of 45 seconds. An entry of zero seconds
will disable the Fallback feature.
This parameter tells the control algorithm when to stop trying to reacquire the target flow
rate. When the remaining volume of the load is equal to the value specified by this
parameter, no further attempts will be made. Set the parameter to the same value as
st
the 1 Stage Trip Volume, plus 50 gallons. An entry of zero will disable the Fallback
feature.
If this parameter is not zero, MultiLoad will try to ensure a minimum backpressure on the
line. It will reduce the flowrate by the size of the deadband or the configured Fallback
decrease rate until the minimum pressure is reached. If this pressure is maintained as
long as the retry time, MultiLoad will try to increase the flow by the amount of the
deadband or the configured Fallback increase rate until the original flow rate is achieved.
If this value is maintained MultiLoad will not look to the Fallback Rate parameter.
If during pressure control the flow rate goes under the fallback minimum rate, MultiLoad
will generate an FBPress Alarm. If this value is zero the alarm will be never raised.
The Fallback Increase Rate is the step size to increase flow rate, when the MultiLoad
wants to recover his flow rate. This function is only used for pressure control. If the step
size is zero the MultiLoad will use the Deadband of the current flow stage as step size.
The Fallback Decrease Rate is the step size to decrease flow rate, when the MultiLoad
wants to recover his flow rate. This function is only used for pressure control. If the step
size is zero the MultiLoad will use the Deadband of the current flow stage as step size.
If the pressure goes over this value, MultiLoad will retry to go to the configured flow rate.
If this value is zero, MultiLoad will start to recover when we are above the Fallback
Minimum Pressure.
If this parameter is enabled, the pressure control will use the sum of the calculated vapor
pressure (GPA TP-15) and the Fallback Minimum Pressure, as Minimum Fallback
Pressure. If the pressure drops under this sum MultiLoad will try to close the valve, to
increase pressure on the line.
Select the desired API table to correct liquid volumes to a reference temperature or
pressure. Highlight the field and press Enter to scroll through the choices.
Product name needs to be selected In conjunction with the API table 54YG
When enabled, VCF values from extrapolated table ranges can be used for CTL and
CPL calculations without raising an API Table Alarm.
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