Span Data - Siemens SITRANS F Operating Instructions Manual

Section 2
Use this menu to set the
low and high range for
analog outputs.
Use this menu cell to
enter a calibration
slope factor for
volumetric flow (Vfo).

2.7.1 SPAN DATA

The Span Data menu allows you to set 0% and 100% output limits for volumetric flow (Vfo), absolute
flow (Vfab) and sonic velocity (Vs). Each menu cell shows appropriate rate units and time base. If you
change flow rate units after spanning the system, the computer automatically updates the output data
setup to reflect the change. Span limits apply to both the analog outputs and the on-screen stripchart.
In addition, temperature ranges can be set if an optional temperature sensor is supplied.
The flow outputs operate as follows:
Vfo
Spanned Volumetric
Flow Rate:
Vfab
Spanned Absolute
Volumetric Flow Rate:
Vs
Spanned Liquid
Sonic Velocity:
Maximum span values represent: Minimum span values represent:
100% of span
Current output of 20 mA
Voltage output of 10 Vdc
Pulse output of 5000 Hz
NOTE: If necessary, analog outputs can be "trimmed" in the Meter Facilities mode.
Siemens 2 Channel [1]
Define data Alarm thresholds
Span Data
Set Alarm Levels
Calibrate Flowrate
Data Span/Set/Cal
The minimum and maximum flow rate entries establish the Vfo span.
The [Max Flow] menu cell sets 100% of span. The [Min Flow] menu cell
sets 0% of span. Use signed numbers for bi-directional spanning. Note
that negative (reverse) flow always is lower than positive flow, whatever
its absolute magnitude. For example, for a flow measurement range of -
30 GPM to +10 GPM, the 4 mA span will be -30 GPM, and the 20 mA
span will be +10 GPM.
Vfab is the absolute magnitude of the volumetric flow rate (Vfo). There
are no menu cells provided to span this output. Vfab shares the Vfo
span entries. The Vfab minimum span is always zero. The maximum
span for Vfab is the largest absolute value of either the min. or the max.
flow rate (Vfo) entries. For example, a span between +10 GPM and -30
GPM, spans the Vf output from 0 GPM to 30 GPM.
Vs is the sonic velocity in meters-per-second (m/s) of the flowing liquid.
The min. and max. Vs entries establish the Vs span. Max Vs (m/s)
defines 100% of span. The Min Vs (m/s) defines 0% of span.
2-39
Channel 1
Intrinsic
0% of span
Current output of 4 mA
Voltage output of 0 Vdc
Pulse output of 0 Hz
1010PFM-3G
Use this menu to define
setpoints for the alarm
relay outputs.