KROHNE ALTOSONIC III EN - Manual (Page 22)

ALTOSONIC III 22
3.11.4 Main menu 3.00.00
Installation
Submenu 3.01.00 Volume flow parameters
Function 3.01.01 Full-scale value for 100% volume flow rate
The following units can be applied:
m³/s - cubic meter per second – US Gal/s - US gallons per second
m³/min- cubic meter per minute – US Gal/min - US gallons per minute
m³/hr- cubic meter per hour – US Gal/hr - US gallons per hour
L/s - liter per second - bbls/hr - barrels per hour
L/min -liter per minute - bbls/day - barrels per day
L/hr -liter per hour - free unit, a user-definable unit, which can be defined using Function 3.07.05 to 3.07.07.
Range depends on diameter (D) and volume flow velocity (v):
Q
min
[m³/h] = 0,9 x D² (v
min
= 0.5 m/s)
Q
max
[m³/h] = 31,25 x D² (v
max
= 20 m/s)
Q
min
[US GPM]= 3,9 x D² (v
min
= 1.5 feet/s)
Q
max
[US GPM] = 138 x D² (v
max
= 20 m/s)
Function 3.01.02 through 3.01.03 Zero value / Zero calibration
Although zero calibrated at the factory the flow sensor might still give an offset flow reading, at "zero" flow in the
pipeline (measuring tube completely filled with medium. Function 3.01.02 ZERO VALUE can be used for zero
calibration. It can be set to either FIXED, which will give a factory zero setting, or MEASURED, which will allow to
compensate for the small signal using Function 3.01.03 ZERO CAL.
Function 3.01.04 Master time constant of display and outputs
This is the time that it takes for the display and the current and pulse outputs to reach 66% of the end value, after a
change in the flow rate. The time constant does not apply for totalization. The time constant does not apply for the
current output in F/R setting. If required, a different time constant value can be set for the pulse/frequency output under
Function 3.05.06 TIME CONST.
Function 3.01.05 through 3.01.07 Low-flow cut off for display and outputs / Cut off "on" value/ Cut off "off"
value
Due to the extreme low flow sensitivity of the ALTOSONIC III, it will detect the slightest movement of fluid, even at zero
flow. To avoid these measurements causing outputs and totalizer changes, the low flow cut-off can be used to force
reading to zero. These are set as a percentage of Full Scale, as configured in Fct.1.01.01 or 3.01.01.
When the flow rate decreases below the "on" value, the display and outputs are set to their "zero" values. When the
flow increases above he "off" value, measurements are resumed. The "off" value must be larger than the "on" value by
at least 1%. With Function 3.01.05 LF CUTOFF set to NO, factory settings are used for the "on" and "off" values.
Function 3.01.08 Meter size
The nominal diameter of the measuring tube. See the flow sensor nameplate. This value can be entered In mm or in
inches.
Function 3.01.09 Flow sensor constant GK
At the factory, each flow sensor is calibrated and supplied with a calibration constant. This constant can be found on the
flow sensor nameplate.
Function 3.01.10 Definition of forward flow direction
The forward flow direction is indicated with an arrow on the flow sensor. If the actual flow is in the direction of the arrow
then the flow is in the positive direction and the converter will have a positive flow reading. By setting this function to
NEGATIVE, the converter's reading can be reversed. This can be useful when the process flow direction is changed so
the flow sensor will not need to be reversed.
Function 3.01.11 through 3.01.12 Minimum/Maximum velocity of sound
In media of varying composition, the ultrasonic wave speed will vary, like in oil-water mixtures. This is identifiable by
means of measuring the velocity of sound. The current output and the pulse output can be programmed to indicate the
velocity of sound, see Function 3.04.01 and 3.05.01. Their "zero" values (0% scale) will then correspond with the
velocity of sound set in Function 3.01.11 MIN VOS, where their "full-scale" values (100% scale) will correspond with the
velocity of sound set in Function 3.01.12 MAX VOS. See also Function 3.03.06 VOS for the display of the velocity of
sound. NOTE: Only necessary for setting span for outputting VOS, is not needed to measure flow!
Submenu 3.02.00 Version
Function 3.02.01 Function of converter
The function of the converter is factory preset to CUSTODY and can not be altered.