PicoLog Self-Help Guide
AR346-1
© Copyright 2014 Pico Technology Ltd.
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This is inherent in the hardware design and cannot be changed or fixed in software.
Streaming at 1 ms sample time to multiple 1 MS files
For PicoLog, you must select in the Recording dialog:-
•
Streaming (Single converter only) and not Real Time Continuous for the recording
method.
•
Repeat after Delay as the action at end of run.
•
1 second as the restart delay.
In the PicoScope2000 Streaming dialog:-
•
Number of Samples = 1000000
•
Sample Interval = 1 (ms)
•
Channel A and Channel B ranges must be ±2 V. (or higher if you wish, but not
lower).
•
AC or DC as required.
When you start logging, 1 million samples per channel will be saved to the data file you
have set up at 1 ms sampling. When 1 million samples are reached, a new file is started
with an auto-incremented file name. This cycle will continue as long as there is hard disk
space available.
Logging a 4-20mA sensor using a PicoScope 2203, 2204 or 2205
Below is a description of how to use an 8-bit PicoScope 2203, but the 10-bit PicoLog
1012 or 12-bit PicoLog 1216 would give more resolution, if required.
With the PicoScope 2203/4/5, it would be simple to use a 50 Ω, through-terminator for
the load resistor necessary at the BNC input. This is a standard product from RS
Components. 546-4695, £9.80. It is in fact just a BNC male to female connector with a
50 Ω resistor in parallel internally. Calculating for 50 Ω, 4 mA now equals 200 mV input,
and 20 mA now equals 1 V input.
Assuming you have connected up the sensor, terminator and scope, you just need to set
the scaling for the channel in question. We will illustrate how to set-up channel 1 for
4-20 mA operation with graph scaling from 0 bar to 10 bar.
1.
Start PicoLog and set-up your sample rates as required.
2.
When you get to setting up channel A (PicoScope2000 Edit Measurement):
a.
Type Pressure as the Name and ±1 V as the Voltage range.
b.
Leave the Measurement as DC Volts and the Scan Time as it is.
3.
Now click Options.
4.
In the Parameter Options dialog, tick Use parameter Formatting, and put bar in
the Units box. Field Width = 4, Decimal places = 2, Minimum value = 0,
Maximum value = 10.
5.
Now click Scaling to go to the next dialog.
6.
In the Parameter scaling dialog, select Table Lookup as the Scaling method and in
the text box, type:-
0.2 0
1.0 10
Note: there is a space between the two numbers on each line