Move through the menus with left/right arrows. When a menu appears, press highlighted
key for that option.
PCL812 measurements all use single channel (10 or 11 I think, but I advise you to check)
PCL812 is expected to be found at 220h port; but in case yours is not there, I guess
you can ask me to rewrite that and send you a new version of the EXE file
HP3457A needs to be attached to PC by IEEE488 interface.
Additional utility GRAFEX.EXE is added to this package. Instructions at the bottom of
MENU 1 - ABOUT
Nothing much to do with this menu. Btw, it informs you that you can press F1 in almost
any moment to get the help on the current action, but since you probably don't speak
Serbian, then you need to read this file instead.
MENU 2 - CONFIGURATION
O - "opseg A/D kartice"
Voltage range of PCL812 A/D card. It can't be neither read nor written by software.
You must specify it manually. It depends on the states of switches on the card.
Possible values are 1,2,5 and 10.
V - "vremenska osnova A/D kartice"
Time base for PCL812 measurements. Means time between two samples are taken. Opposite
of sampling frequency. Units are milliseconds (0.001 sec). Least possible value is 3.
This is due to use of DOS' event wait service, which is limited to 2-3 ms, depending
on the BIOS. Sorry, my program records just slow processes, and doesn't use DMA.
IMPORTANT NOTE: real time is not exactly the time my program shows. You must divide
it by a factor, which depends on the time base:
3-41 -> divide by 1.024
42-83 -> divide by 1.012 (1+0.024/2)
84-124 -> divide by 1.008 (1+0.024/3)
125-166 -> divide by 1.006 (1+0.024/4), etc.
Note for those who do understand what writes in the instructions on the subject:
there's a slight mistake, it says "multiply" instead of "divide". Right thing to do
is divide: means 1 second of Instrument Manager's time equals 1/1.024 seconds of real
time (for 3-41 ms time bases).
H - "vremenska osnova HP3457A"
The same for HP3457A multimeter. All the same applies. And, note, our HP3457A could
not perform measurements for less than half a second. So don't waste your time trying
to make it sample at 100 Hz or so.
G - "grafici"
H - horizontal net (press H, then up/down arrows, to adjust density between
0 and 2)
V - vertical net (the same)
T/D - T for 1-pixel and D for 3-pixel width of function on a graphic
M - label x-axis each N pixels (adjust number N)
S - "snimanje CFG fajla"
Save configuration (the above parameters).
U - "ucitavanje CFG fajla"
Load previously saved configuration. Both actions are followed by a "positive" beep,
MENU 3 - MEASUREMENTS
F2 - PCL812 as digital voltmeter
F4 - PCL812 as analogue voltmeter
F6 - HP as digital voltmeter
F8 - HP as digital ammeter
F10 - HP as two-wire digital ohmmeter
F12 - HP as four-wire digital ohmmeter
After calling any of the above functions, press ENTER to start recording to memory.
64000 bytes allocated, means 32000 integer results, or 10666 floating point results.
Integer results come from PCL812 operations without linearization [sp?]. Other
operations give floating point results. ESC ends a measurement.
MENU 4 - ANALYSIS
1 - analyze 1st order system
Means a system with response of type y=1-exp(-kt). Like you have a thermometer in
the cold water, then you put it in the warm water, and observe how its output slowly
reaches final value.
2 - analyze 2nd order system
Means a system with response of type y=[exp(-kt)]*[sin(wt)]. Like oscillating console
equipped with some position sensor.
L - linearization [sp?]
Means measurements, graphics, and stuff, don't have to give you ordinary results in
volts. You can make them display temperature. Just use one of two available
linearization formulas (for two common types of temperature sensors). After pressing
L, submenu says:
0 - no linearization
1 - Pt/Si resistance sensor; formulae will be written on the screen when you
press 1, you just have to enter the parameters
2 - NTC (negative temperature coefficient) termistor [sp?]; again, you just
have to enter the parameters
After choosing linearization of type (1) or (2), the program will ask you if you
measure O - resistance, N - voltage, or S - current. Then all the results in volts
will be calculated due to respective formulas before displaying (except in analogue
Huh, analyzing 1st or 2nd order system would require a lot of typing to explain.
Anyway try my sample files and see what it's about. Use dip1.* for 1st order system and
dip2.* for 2nd order system. 1st order system analysis gives you time offset and time
constant (plus some less important things). 2nd order system analysis gives you
oscillating frequency and... (I don't know proper English term) muffling coefficient?
1st order system analysis applies on original results. 2nd order system analysis
applies on filtered data. It all doesn't have anything to do with turning digital filter
on or off (option from the next menu).
Numerous errors can be reported by these routines. Most common one is "ne odgovora
oblik funkcije", means "function shape not proper". There are some rules signal has to
obey in order for these routines to work, and I don't remember all of them... it's been
a while since I wrote this program :(
After pressing 1, you'll be asked if you want to use the correction (d/n=y/n). If
you answer yes, you have to enter high limit of (normalized) signal to be used in
calculating sensor time constant, in percents. Use the correction if your system isn't
exactly a 1st order system (like ordinary thermometer when water around it is not mixed;
that's how dip1.xxx was recorded).
MENU 5 - DISPLAY
Message "nema podataka u memoriji" means there's no data in the memory; neither did you
perform a measurement nor did you load a data file.
G - "grafik"
Displays a graphic. You can condense or decondense it (x-axis only) by pressing K
T - "tabela"
Displays a table. Move through it using ordinary keys: arrows, PgUp/Pgdn, Home/End.
F4 - No theoretical curve for 1st order system graphic. Default.
F8 - User's theoretical curve for 1st order system graphic. Students use this one at
lab classes to see if the parameters they calculated fit the real ones. You have to
type time offset and time constant if you use this option.
F12 - Computer's theoretical curve for 1st order system graphic. You must call 1st order
system analysis before you can use this option.
F - "digitalni filtar"
Digital filter: "iskljucen" means "off", "UKLJUCEN" means "on".
MENU 6 - FILES
S - save file (measurement results currently in memory)
U - load previously saved file
F5 - change current directory for saving/loading data files manually
F12 - change current directory by calling NCD (Norton Change Directory)
ESC - exit
ADDITIONAL UTILITY - GRAFEX.EXE
Results of measurements are recorded in specific format which can be read only by
Instrument Manager. If you want to export them, and use them in programs like grapher,
origin, matlab, etc. you need to use grafex, which creates ASCII text files. After
calling grafex, you will be asked for following parameters:
- input filename
- output filename (without extension which will be DAT); if the file exists, you will
have to press any key except ESC to overwrite it
- do you wish to convert all data (d/n=y/n)
- from position (only if you answer no)
- to position (only if you answer no)
- each n-th (if your process was too slow compared to sampling frequency, you may choose
to extract only each n-th result)
Yes, I know these instructions are quite incomplete, but I'm too lazy to translate half
of my graduate work to English. If you're interested in anything specific: