KROHNE VFM 3100 EN - Manual (Page 26)

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2.5. Preconfiguring the VFM 3100
With the HART Communicator, the database can be generated off-
line and then downloaded to the transmitter. The procedure for buil-
ding the database consists of entering the appropriate information
as it is requested.
NOTE: The password for the local display configurator cannot be
configured from the HART Communicator.
2.6. Displaying the Configuration Database
HART Communicator (Review Menu).
The parameters in the configuration database can be viewed without
entering the Setup Menu. This is done via the Review Menu.
Local Configurator (Display Menu).
The parameters in the configuration database can be viewed without
entering the Configuration Menu. This is done via the Display Menu.
2.7. Adjusting the VFM 3100
The following four adjustments can be made to the VFM 3100:
mA Calibration (D/A Trim)
Total Reset
Low Flow Cut-In
Upper Range Value
These appear in various places in the structures
(refer to chapter 7 and 8).
2.7.1. mA Calibration (D/A Trim)
This function allows the 4 to 20 mA output of the transmitter to be
calibrated or matched to the calibration of the receiving device.
NOTE: The transmitter has been accurately calibrated at the factory.
Recalibration of the output is normally not required unless it is being
adjusted to match the calibration of the receiving device
2.7.2. Total Reset
This function allows the flow total to be reset to zero
2.7.3. Low Flow Cut-In
The low flow cut-in parameter allows the user to set the level above
which the VFM 3100 begins to measure flow, i.e., the lower range li-
mit of the VFM 3100. This process can be carried out automatically if
the flow is turned off. Otherwise, manual selection from the following
pick-list of eight levels can be made:
Auto, (LO), (L1), (L2), (L3), (L4), (L5), (L6), (L7)
For convenience, these levels are displayed as estimated flow rates
in the selected flow units. The value of these flow rates depend on
the specific application parameters.
With the HART configurator the current value is displayed, and you
can elect to decrease or increase the level by one. If the level does
not change when this is done, the minimum or maximum level has
been reached, respectively. In the case of the local configurator you
can select the desired level from the displayed pick-list.
If Automatic mode is selected, the VFM 3100 chooses the lowest
level at which no signal is detected over a 20 second time interval.
You may wish to increase or decrease this setting. For instance, noi-
se signals could be occurring at an interval greater than 20 seconds
and possibly not be detected during the automatic selection pro-
cess. Repeating the auto-selection process helps to avoid this pos-
sibility.
2.7.4. Upper Range Value
This parameter sets the desired maximum flowrate of the VFM 3100.
2.8. Reading the Measurements
The Process Variable Menu (HART) or the Measurement Menu (Lo-
cal) provides periodically updated values of the flow rate, vortex fre-
quency (frequency in), scaled pulse frequency (frequency out), and
flow total. The fllow rate and total are presented in units of volume or
mass as configured, the frequencies in Hz. Due to the limited size of
the local display only one parameter is displayed at a time. It is possi-
ble to configure the device to display in succession two, three, or four
of the variables, as selected from a pick-list.
2.9. Testing the VFM 3100 and Loop
(Test Menu)
Entering the Diag/Service Menu for the HART Communicator or Test
Menu for the Local Configurator allows the following two test proce-
dures to be activated:
• Self-Test
• Loop Test or Loop Calibration
2.9.1. Self-Test
This selection checks transmitter operation by injecting, near the
front end of the electronics, an internally generated periodic signal of
known frequency. The frequency of this signal is in turn measured
and checked against the injected signal.
2.9.2. Loop Test or Loop Calibration
This selection allows the transmitter to be used as a signal source to
check and/or calibrate other instruments in the control loop, such as
indicators, controllers, and recorders. The mA, scaled pulse, and di-
gital output signals can be adjusted to any value within the range li-
mits of the VFM 3100.
2.10. Electronic Module Replacement
If an Electronic Module is shipped as a replacement, the correct flow-
tube parameters will not reside in its configuration database. For pro-
per operation of the VFM 3100, the correct values must be entered.
If the configuration database from the original VFM 3100 was saved
to a file, this file, containing the correct flowtube parameters, can be
downloaded to the new transmitter. If this is not the case, they must
be entered manually from the VFM 3100 tag.
In the latter case, enter the following data first when configuring the
VFM 3100!
• Model Code: Enter alphanumeric Model Code from VFM 3100
body tag (first 14 characters).
NOTE: If a Model Code beginning with the letter 'E' is entered via the
local configurator, a prompt screen will be displayed requesting that
the VFM 3100 configuration be selected from the following list:
- Single Measurement
- Dual Measurement
- Single Measurement with Isolation Valve
- Dual Measurement with Isolation Valve
This capability is NOT available with the HART configurator; hence,
the local configurator must be used to enter the flowtube parameters
if the Model Code begins with the letter ‘E’.
If the Model Code does not begin with an 'E', the above information
is read directly from the Model Code.