Dwyer GFT2 - Manual (Page 6)

Submenu “User-Defined Units”
In addition to conventional flow units, user-defined flow engineering units may be
selected. Use the “Engineering Units and K-Factor Menu” to navigate to the “User
Defined Units” menu option. This option enables user-defined configuration of any
engineering unit required for process measurement.
The following three parameters are available for this function:
1. UD Unit volume K-Factor (defined in Liters)
2. UD Unit time base (defined in Seconds)
3. UD Unit use density (units with or without density support)
Before using User-Defined Unit, make sure the proper conversion factor of the new
unit with respect to one liter is set (the default entry is 1.00 Liter). Also, proper time
base values for User-Defined Units must be set.
The following selections are available: 1 second, 60 seconds (1 minute), 3600
seconds (1 hour), 86400 seconds (1 day). The default entry is 60 seconds. If a
mass based User-Defined Unit is desired, then “UD Unit Use Density” parameter
must be set to “YES”. The default entry is “NO”, so Fluid STD Density parameter is
not used for flow rate calculation.
Submenu “K-Factors Settings”
Conversion factors relative to Nitrogen are convenient to use when flow
meter/controller mated to GFT2 is calibrated for Nitrogen and another gas is
required to be measured/controlled.
Conversion factors relative to Nitrogen, for up to 22 common gases, are stored in
the GFT2. In addition, provision is made for a user-defined conversion factor.
Conversion factors may be applied to all units of measure (except %FS unit) via
LCD/Keypad or serial communication interface.
The following three parameters are available for this function:
K-Factor Mode: Disable, Internal Index, User-Defined (default Disabled)
Internal K Factor Index: 1 – 22 (from internal K-Factor table)
User-Defined K-Factor: 0.001 – 999.9 (default value is 1.000)
NOTE: The conversion factors will not be applied for % FS engineering unit.
Submenu “Alarm Settings”
GFT2 provides the user with a flexible alarm/warning system that monitors the Fluid
Flow for conditions that fall outside configurable limits, as well as visual feedback
for the user via the LCD or via an optically-isolated output. The Flow Alarm has
several attributes which may be configured by the user via LCD/Keypad or serial
communication interface. These attributes control the conditions which cause the
alarm to occur and to specify actions to be taken when the flow rate is outside the
specified conditions.
Depending on the GFT2 function configuration (flow meter or controller) there are
two Alarm algorithms. If GFT2 is configured as flow meter, flow Alarm conditions
become true when the current flow reading is equal to or higher/lower than
corresponding values of high and low flow Alarm levels. If GFT2 is configured as
flow controller, flow Alarm conditions become true when difference between Set
Point value and current flow reading is equal or higher/lower than corresponding
values of High and Low Flow Alarm levels.
Alarm actions can be assigned with preset Delay Interval (0-3600 seconds) to
activate the optically-isolated output (separate for High and Low alarm). Latch
Mode control feature allows each optical output to be latched on or follow the
corresponding alarm status.
The following settings are available for Flow Alarm (see Figure 10):
a) Flow Alarm Mode (Tabular entry)
This function determines whether Flow Alarm is Enabled or Disabled. The following
sections are available: Enabled or Disabled. The default entry is Disabled. Alarm
Mode selections can be set with the UP and DN buttons and are accepted by
pressing ENT button.
b) Low Flow Alarm (Numerical entry)
The limit of required Low Flow Alarm value can be entered in increments of 0.1%
from 0 – 100% FS.
If a Low Alarm occurs and one of the two optional outputs is assigned to the Low
Flow Alarm Event, the optically-isolated output will be activated:
1) For Flow Meter Function: when the flow is less than the Low Flow Alarm value.
2) For flow controller function: when the absolute difference between Set Point
value and actual flow reading is equal or more than the Low Flow Alarm value and
Actual Flow value is less than Set Point value.
The Low Flow Alarm condition is also indicated on the corresponding Process
Information Screen displaying L character.
NOTE: For Flow Meter function, the value of the Low Flow Alarm must be less than
the value of the High Flow Alarm
c) High Flow Alarm (Numerical entry)
The limit of required High Flow Alarm value can be entered in increments of 0.1%
from 0 – 100% FS. If a High Alarm occurs and one of the two optical outputs is
assigned to the High Flow Alarm Event, the optically-isolated output will be
activated for:
a) Flow Meter function: when the flow is more than the High Flow Alarm value.
b) Flow Controller function: when absolute difference between Set Point value and
Actual Flow reading is equal or more than the High Flow Alarm value and actual
flow value is more than Set Point value.
The High Flow Alarm condition is also indicated on the corresponding Process
Information Screen by displaying H character.
NOTE: For Flow Meter function, the value of the High Flow Alarm must be more
than the value of the Low Flow Alarm.
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
Table 4: Supported Engineering Units List
Flow Rate
Engineering
Units
%FS
ml/sec
ml/min
ml/hr
ml/day
litr/sec
litr/min
litr/hr
litr/day
m^3/sec
m^3/min
m^3/hr
m^3/day
f^3/sec
f^3/min
f^3/hr
f^3/day
gal/sec
gal/min
gal/hr
gal/day
gram/sec
gram/min
gram/hr
gram/day
kg/sec
kg/min
kg/hr
kg/day
lb/sec
lb/min
lb/hr
lb/day
Mton/min
Mton/hr
lgal/sec
lgal/min
lgal/hr
lgal/day
MilL/min
MilL/hr
MilL/day
bbl/sec
bbl/min
bbl/hr
bbl/day
User
Totalizer
Engineering
Units
%s
ml
ml
ml
ml
litr
litr
litr
litr
m^3
m^3
m^3
m^3
f^3
f^3
f^3
f^3
gal
gal
gal
gal
gram
gram
gram
gram
kg
kg
kg
kg
lb
lb
lb
lb
Mton
Mton
lgal
lgal
lgal
lgal
MilL
MilL
MilL
bbl
bbl
bbl
bbl
User
Description
Percent of full scale
Mililiter per second
Mililiter per minute
Mililiter per hour
Mililiter per day
Liter per second
Liter per minute
Liter per house
Liter per day
Cubic meter per second
Cubic meter per minute
Cubic meter per hour
Cubic meter per day
Cubic feet per second
Cubic feet per minute
Cubic feet per hour
Cubic feet per day
Gal per second
Gal per minute
Gal per hour
Gal per day
Grams per second
Grams per minute
Grams per hour
Grams per day
Kilograms per second
Kilograms per minute
Kilograms per hour
Kilograms per day
Pounds per second
Pounds per minute
Pounds per hour
Pounds per day
Metric Ton per minute
Metric Ton per hour
Imperial Gal per second
Imperial Gal per min
Imperial Gal per hour
Imperial Gal per day
Million Litr per minute
Million Litr per hour
Million Litr per day
Barrel per second
Barrel per minute
Barrel per hour
Barrel per day
User Defined