Honeywell SMV 3000 - Manual (Page 86)

SMV 3000 Transmitter User’s Manual 1/99 74
6.10 Using Custom Engineering Units
Using Custom Units
for PV4 Flow
Measurement The SCT contains a selection of preprogrammed engineering units that you
can choose to represent your PV4 flow measurement. If you want the PV4
measurement to represent an engineering unit that is not one of the
preprogrammed units stored in the SCT, you must select custom units and
enter a tag that identifies the desired custom unit.
Using the SCT, selecting Custom Units allows you to choose a unit that is
compatible with your application process. Additionally, a conversion factor
must be calculated and entered when configuring the PV4 flow variable.
This conversion factor is a value used to convert the standard units used by
the SMV into the desired custom units. The standard units used by the SMV
are:
•
Tonnes/hour – for mass flow
•
Meters
3
/hour – for volumetric flow
For example, to calculate the conversion factor for a volumetric flow rate of
Standard Cubic Feet per Day – SCFD
2 55 . 847
3 3
3048 . 0
3
• = • =




























hr
m
n i Flow
day 1
hr 24
m
ft
hr
m
in Flow SCFD in Flow
Conversion Factor = 847.552
For example, to calculate the conversion factor for a mass flow rate of
Kilograms per day – kg/day
24000
001 .
• = • =
























hr
t
n i Flow
day 1
hr 24 kg
hr
t
in Flow kg/d in Flow
Conversion Factor = 24000
This factor is then entered as the Conversion Factor value in Flow
Compensation Wizard of the SCT during configuration. Please note that
when using the standard equation, the conversion factor, as well as other
values, are used to calculate the Wizard Kuser factor. When using the
dynamic corrections equation, the conversion factor is used as the Kuser
factor.
Refer to the SCT on-line manual for additional information about using
custom units in your SMV 3000 configuration.