Site Setup Menu Items; The [Hf] Menu Item; Using The [Hf] Menu Item - Siemens SITRANS FUH1010PVDX Operating Instructions Manual

Section 6
fx (drive) Current Transmit drive code selected during Initial Makeup. The drive code con-
trols the sonic transmit signal.
N (burst length) Transmit burst duration selected during Initial Makeup. To change N count
press <Right Arrow>. At equal sign enter numeric value (1 to 9 only).
Ltn (in/mm) Spacing distance between the transducers. It will be in inches or millimeters,
depending on default units.
Vfmax The flow velocity (in selected units) corresponding to one whole cycle offset
between upstream and downstream receive signals.
Vs max m/s Maximum correctly calibrated Vs for current transducer spacing.
Vs min m/s Minimum correctly calibrated Vs for current transducer spacing.
Empty % Value of Empty Alarm Setting. The meter will declare an empty status if signal
strength drops below this value.
Samples/Cycle Digital sampling rate.
Max Damping Maximum signal damping. Use to average digital data when an unstable condi-
tion occurs.
Min Damping Minimal signal damping. Use to average digital data when an unstable condition
occurs.
HF Flow registration correction parameter.

The [HF] Menu Item

All 1010 flowmeters with version 3.01.02 and later operating systems include a Diagnostics Menu item
that permits the entry of a flow registration correction parameter labeled [HF]. This "HF" parameter is
the input for a proprietary algorithm which automatically compensates for signal beam blowing in pipes
utilizing either 1011 clamp-on or insert transducers, thereby extending the upper flow limit of all 1011
flowmeters. This algorithm provides the most benefit for clamp-on gas meters where high flow velocities
and low gas sound velocities create the most challenging conditions for digital signal processing routines.

Using the [HF] Menu Item

Two methods for adjusting this parameter are provided via the [HF] menu cell, located within the
"Diagnostics/Site Setup" submenu. The "Manual" method provides direct entry of this parameter and is
primarily intended for the advanced user, whereas the "Automatic" method allows the 1010 flowmeter
to automatically measure the required correction and install the parameter.
Guidelines for using the [HF] menu item are described below:
This menu is only accessible for the transducer channels, not the virtual (average flow) channel
of the flowmeter. (i.e., Diagnostics Path 1 or Path 2, but not Path 1 & 2).
The 1010 flowmeter will inhibit the "Automatic" installation of the [HF] parameter if the flow rate
is insufficient (too low) to accurately measure the required correction. If the maximum flow rate
for the application is relatively low then this correction should not be required.
If the flow rate is very high and the flowmeter is reporting erroneous or unstable flow, then the
flowmeter may already be having trouble resolving the upstream and downstream signals. In
this event, it may be necessary to first lower the flow rate to a moderate level before performing
the "Automatic" HF adjustment. Once this is done the flowmeter should be able to properly
measure the highest flow rates without problems.

SITE SETUP MENU ITEMS

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CQO:1010PVXFM-3