Fluid Components International GF90_GF92 - Manual (Page 55)

Doc. No. 06EN003229 Rev. H 51 GF Series Flow Meter Models GF90/GF92
FLUID COMPONENTS INTERNATIONAL LLC http://www.fluidcomponents.com
In the example above, the pipe line could contain nitrogen, hydrogen or methane. The gas analyzer's
4-20 mA output is connected to the flowmeter's Auxiliary port. The gas analyzer outputs 4 mA when it
detects nitrogen, 12 mA when it detects hydrogen and 20 mA when it detects methane. The flowmeter is set
to switch groups when it detects the signal crossing 8 mA or 16 mA. Figure 34 illustrates this graphically.
To enter a new external signal switch point(s) for the Auto-Select mode:
1. Press 4, the Miscellaneous option.
2. Press 1, the Set Group option.
3. Press 2, the Set Auto-Select option.
4. Press 1, the By Aux Input option. Enter the user password (if it is enabled).
5. Enter the number groups involved in the Auto-Selecting. (Zero if there is only one Group of
calibration information.)
6. Enter the digital switch point value that represents the signal level.
Link Groups (Extended Range Emulation)
The Link Groups option enables the flowmeter to measure flow ranges of greater than 100:1 to up to 1000:1.
(Turndown is defined as the maximum flow rate divided by the minimum flow rate.) This function is similar to
the LT Series Extended Range. Links Groups can only be set by the factory. The Link Groups mode operates
transparently (as if the flowmeter were operating in normal mode), although, when changing system
parameters there are a few extra steps that need to be taken.
To determine if the flowmeter is in Link Groups mode:
Press 1, the Normal Operation option. The mode of operation is displayed on the last line. Link is
displayed if the link groups option is enabled.
If the flowmeter's link groups option is enabled, then changes in system parameters must be made for
each group. For instance, if the flow rate units are changed, the flow rate units for each linked group
must be changed.
Group 1
Calibration
Information
Group 2
Calibration
Information
Group 3
Calibration
Information
Gas Analyzer Signal Ouput
4 mA 20 mA
Switch
Point
8 mA
Switch
Point
16 mA
C00254-1
Figure 34. Auto-Select, Switch Point Scheme