HP 82479A Owner's Manual page 87

SYSTEM MONITORING
You can use the system monitoring program, [11H 1 Tl, to continuously display the status of a system on
a video monitor, and to respond to unusual events or conditions. The program can automatically control a
system and/or notify an operator of conditions that require human intervention. The MOMHI TOR
program is particularly suited for production environments since an HP-71 based monitoring system
requires less space than a full-size computer and instrument system, and is less costly.
The minimum components in a monitoring system are an HP-71B Handheld Computer, an HP 82401A
HP-IL Interface, an HP 3421A Data Acquisition/Control Unit, an HP 92198A Mountain Computer
HP-IL 80-Column Video Interface, and a suitable monitor. (If you are using some other display device,
refer to appendix F, "Alternative Peripheral Options.") If the system includes a printer (for example, a
ThinkJet), a printed record of unusual events can be recorded. Since the program is designed to run
continuously, all the devices in the system should be connected to ac power.
The program presents up to 18 traces on the video monitor. Each trace represents a single measurement,
such as the temperature of a vat or the setting of a switch. The [lll I TIE program allows you to choose
one of three formats for the video display.
The default display format presents the label for each trace on the screen, followed by the current value
and a pictorial representation of the reading on a scale. The scale is used to represent the reading within
specified "nominal bounds." For example, if the temperature of a vat is supposed to stay within the range
190 to 200°C, the left edge of the scale could represent 190°C and the right edge could represent
200°C. This allows an operator to see at a glance if the temperature of the vat is drifting low or high.
The default display format is shown in figure 7-1:
SYSTEM MONITOR EXAMPLE
Setup: EXAMPLE Datafile: MYFILE Time: 14:22:35
1 Room temperature 29.21 X
2 Vat temperature 197.23 X
3 Fluid level 8 X
4 Fuel pressure 34.47 X
5 Flow rate
65.78
X
6 Exhaust temp 145.23
X
7 Safety valve 0 OPEN
Figure 7-1. Video Display With Seven Traces
The second display option is the bar graph format. This format is the same as the default format except
that the reading is shown on the scale in bar graph form using inverse video.
7-1