KROHNE ALTOSONIC III EN - Manual (Page 24)

ALTOSONIC III 24
Abbreviations used:
I Current output
QF Forward volume flow rate
I
0%
Current output at 0 % scale
I
100%
Current output at 100 % scale
QR Reverse volume flow rate
I
max
Current output maximum
When VOS or signal gain is set, only the forward characteristic applies.
Function 3.04.03 Range of current output
The range of the current output can be set to standard 0-20mA or 4-20 mA or to “other” for other user specified spans.
Max reading is 22 mA. The range for “other” is set using functions 3.04.04 to 3.04.06.
Function 3.04.04 0 pct
mA setting for 0 percent of the range. It can be set between 0 and 16 mA. Default is 4 mA.
Function 3.04.05 100 pct
mA setting for 100 percent of the range. It can be set between 4 and 20 mA. Default is 20 mA.
Function 3.04.06 Limit
Limit of current output. Max setting and default setting: 22 mA. Limit it to 20mA when safety systems reserve higher
currents as Fault Codes.
Submenu 3.05.00 Pulse / frequency output
Function 3.05.01 Function of pulse output
The pulse output can be programmed for the following functions:
• OFF switched off, contact closed.
• ACT FLOW proportional with the actual volume flow, see Function 3.01.01 FULL SCALE.
• CORR FLOW proportional with the corrected volume flow, availability depending on version, see Function 3.02.01.
• F/R IND forward/reverse flow indication, see Function 3.01.10, contact closed for forward flow, contact open for
reverse flow.
• VOS proportional with the velocity of sound, see Function 3.01.11 through 3.01.12.
• DIG OUTPUT digital output, see Function3.05.03.
• SIGN GAIN, gain of sensor amplifier, proportional with the signal level, see Function 3.03.11.
Function 3.05.02 Direction of pulse output
Only available when ACT FLOW is selected in Function 3.05.01. When FORWARD is selected, the pulse output will
only be active when the flow is in the forward flow direction as defined in Function 3.01.10 FLOW DIR, while when
BOTH is selected, the pulse output will be active in both flow directions.
Function 3.05.06 Time constant of pulse output
The time constant of the pulse output can be set to 25 ms, which is the lowest value, or MASTER TC, which will result
in the value, set in Function 3.01.04 MASTER TC. The time constant setting only applies to actual flow and corrected
flow.
Function 3.05.07 pulse output function
The function of the pulse output can be set to either PULSE RATE (frequency) or PULSE/UNIT (Totalizer pulse).
PULSE RATE: Is set by entering a frequency at 100 % volume flow rate.
PULSE/UNIT: Is set by entering a value for the number of pulses for each volume (or energy) unit. Each pulse having a
fixed volume, i.e. 1 pulse / 0.1 liter. This is the best method of remote totalizing, as pulses simply need to be counted,
i.e. 10 pulses = 1 liter. See Function 3.05.08 through 3.05.10.
Function 3.05.08 Pulse rate
If the function of 3.05.07 is set to pulse rate, the frequency of the pulse can be set that will be available at 100% flow.
The frequency can be set to: pulse/s, pulse/min, pulse/hr. The default setting is 1000 pulses/second (Hz), the max
setting is 1500.
Function 3.05.09 Pulse/unit
If the function of 3.05.07 is set to pulse/unit, the unit and number of pulses per unit can be set for the flow measurement
using this function. Options are; pulse/m³, pulse/l, pulse/US Gal., pulse/bbl. Also a user definable unit can be set. The
max number of pulses per unit is 7870000, the default setting is 1. NOTE: Check that the max. flow span will not cause
the number of pulses generated per second to exceed the maximum of 2 000 Hz.