KROHNE VFM 3100 EN - Manual (Page 23)

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Item Metric U.S.
Tag blank blank
Flow Units l/min USgpm
Total Units l USgal
Fluid Type Liquid (water) Liquid (water)
Process Temperature 20°C 70°F
Process Density 998,2 kg/m 3 62.301 lb/ft 3
Base Density 999.2 kg/m 3 62.374 lb/ft 3
Flowing Viscosity 1.002 cP 0.9753 cP
Upper Range Value Upper Range Limit for VFM 3100 Size Upper Range Limit for VFM 3100 Size
The units of this default configuration database, i.e., Metric or U.S.,
are established by the units of the Reference K-Factor.
NOTE: These defaults are not recommended for general operation.
If no other process information is available, entering “Liquid”, “Gas”,
or “Steam” as fluid type will establish default data bases as listed on
page 24.
Be sure to read the explanation of each parameter in “Configuration
Database” on page 22 prior to changing the configuration.
The remaining itemg in the database will have the following default
values:
* If the process density and viscosity are provided, the Low Flow
Correction will be set to On.
NOTE: These default values should be changed to match the
specific application. Before making any changes, be sure to read
the explanation of each parameter in “Configuration Database”
on page 22.
2.4. Changing the Configuration
(Configuration Menu)
Using the HART Communicator or the Local Digital Display/Confi-
gurator, any parameter in the configuration database can be
changed to fit the application by entering the Device Setup or Con-
figuration Menu. The specific details for doing this depend on the
configurator, and are described in chapter 7 or 8. Some general in-
formation is presented below.
If the User Information in Table 9 is not supplied with the purchase
order, the transmitter is shipped with the following default set:
Descriptor blank
Date blank
Message blank
Polling Address 0
Noise Rejection On
Signal Conditioning On
Low Flow Correction* Off
Low Flow Cut-In (3rd level above minimum)
Mating Pipe Schedule 40
Piping Configuration Straight
Upstream Distance 30 Pipe Diameters
Custom K-factor Bias 0.0%
Damping Value 2.0 sec
Pulse Output Off
AO/PO Alarm Type Upscale
Flow Units Default units may be changed as desired.
Total Units Default units may be changed as desired.
Noise Rejection Keep default value On.
Signal Conditioning Keep default value On.
Low Flow Correction Should be changed to On if the low end of
the operating range is below a Reynolds
Number of 20,000.
NOTE: If On is selected, actual values of
the process density and process viscosity
must be entered into the database!
Low Flow Cut-In The default value for the Low Flow Cut-In
is the third level above the minimum. After
installing the VFM 3100, this level can be
changed such that under no-flow condi-
tions the flow output is zero.
(See the following section “Adjusting the
VFM 3100” on page 26.)
NOTE: The HART protocol allows the connection of up to 15 HART
devices on a single twisted pair of wires, or over leased telephone
lines, a concept known as ‘multidropping’. In a multidrop installation,
each transmitter is identified by a unique address (1-15) referred to
as the polling address. In the multidrop mode, i.e., if the polling
address is non-zero, the analog output is set to a fixed value of 4 mA.
For a non-multidrop installation, i.e., a single transmitter loop, the
polling address of the transmitter should be left in its default value (0)
if the analog output is intended to indicate flow (4-20 mA). In a
multidrop installation the polling address of each transmitter must
be set to a unique integral value of 1 through 15. This can be done
before or after installation with the local configurator. If using the
HART Communicator, the polling address of each transmitter must
be set individually prior to installing in a multidrop environment.
2.4.2. Transmitter Option
Tag Default tag may be changed as desired.
Descriptor Default descriptor may be changed as desired.
Date Default date may be changed as desired.
Message Default message may be changed as desired.
Polling Address Default address may be changed as desired.
(See note below).
2.4.1. Identification Parameters