GE GFK-0825F - page 155

5-88 Field Control™ Genius® Bus Interface Unit User’s Manual – October 1999 GFK-0825F
5
Custom Scaling
To scale a channel, choose a high and low point and enter the actual input value (span) and a
corresponding engineering units value for each point. During operation, the module will use these
values to convert engineering units into digital values that represent output voltage. Engineering
units values are 16-bit signed integers from -32,768 to 32,767. Span values are signed integers
ranging from -10,000 to +10,000 or 0 to +10,000.
The first scaling scr een sh ows the engineering unit s (AQ ) va l ue that corresponds the low span
(output) value. Valid engineering units are -32768 to 32767.
S:1 CH1 ENG L
-10000
< > chg entr
1. If you want to change the displayed selection, press F3 (chg).
2. Enter the new value using the numeric keypad.
3. Press F4 ( entr) to enter the new value or F3 (clr) to abort the change.
The high engineering un i ts value for the channel is di spl a yed next.
S:1 CH1 ENG H
10000
< > chg entr
If the low and high engineering units values are equal, the output of the channel is:
the minimum output level (0mV) if the AQ data is less than the low engineering units value.
the maximum output level (approximately 10.5V) span value if the AQ data is greater than or
equal to the low engineering units value.
The low span value is displayed next. This is the actual voltage in microvolts that a channel will
output when the low engin eer ing units value is commanded . Span values are changed in the sam e
way that engineering un i ts values are changed. Valid span values are -10,000 to +10,0 0 0 or 0 to
+10,000. In the 0 to 10V range, a negative value for low span can not be configured.
S:1 CH1 SPAN L
-10000
< > chg entr