PicoLog Self-Help Guide
AR346-1
© Copyright 2014 Pico Technology Ltd.
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7.
In the Parameter scaling dialog box, select Table Lookup as the Scaling method
and in the text box, type:-
1799.7 60
1698.7 65
1593.1 70
1482.8 75
1370.7 80
1258.1 85
1147.3 90
1041.9 95
941.5 100
846.4 105
757.9 110
(Please note: there is a single space between the pairs of numbers.)
This tells the program to equate 1799.7 mV to 60 °C on the graph and 757.9 mV
to 110 °C on the graph.
8.
Click OK to go back through the open boxes and channel A should now be scaled
from 50 to 120 °C.
(This sensor is not the most accurate. The data sheet quotes ±2.4 °C at 60 °C, ±3.5 °C
at 85 °C and ±4.6 °C at 110 °C. You may want to choose a better one.)
For a link to the ADC-20/ADC-24 Terminal Board User Guide, please refer to the Related
Documents section in this document.
15.4
Device-specific – PT-104
The PT-104 logger is designed to be very accurate but is designed for fairly stable
temperatures since the thermal response of the PT-100 sensors is quite slow. Each PT-
104 logger takes 720 ms per channel activated, so four channels are read in
2.88 seconds. The temperatures are measured in sequence, to a regular time pattern,
but the readings are only updated once per cycle, all at the same time.
The PicoLog program, running on the local PC, can only access the data by polling the
PT-104 on a regular basis. Normally it requests samples from the logger at a slower rate
than the logger cycles through so that there is always a new reading available. It is
possible to set the sample rate of PicoLog faster than that so it can detect a change in
reading with a worst-case delay of one sample period.
Two or more PT-104 loggers can be controlled by PicoLog and data recorded and
displayed together, but the units are not synchronized with respect to sample time. The
PT-104 loggers are independent so they each log at 2.88-second cycles when four PT-
100 probes are used on each.
For links to the PT-104 Data Logger User’s Guide and the PT-104 Screw Terminal
Adapter (PP660) User’s Guide please refer to the Related Documents section in this
document.
15.5
Device-specific – PicoLog CM3 Current Data Logger
The logger itself has a full-scale reading capability (using a standard 1 mV/A clamp) of
1000 A. It is supplied with 200 A AC clamps, that being the normal recommended
working range. The lower the current, the longer the settling time. It takes about