Lawson Labs, Inc.
800-321-5355 or 610 725-9344
FAX 610 725-9344
www.lawsonlabs.com
lawsnlab@lawsonlabs.com
                                                      4/14/2004

EMF16 Graphics Software for Win 98/NT/ME/2K/XP

A) Basic Operation Instructions

1) Start software and select COM port for EMF16.

2) Click the SignOn button to establish communication. The "RUN"
LED on the EMF16 will light after successful initialization.

3) Click Start Scan to begin and Stop Scan to end.


B) Scan Set Up

1) Pick an internal data rate and remote averaging value. If you 
are running long, slow tests, 10 Hz is the minimum rate. 10 Hz
will also provide the lowest noise. For faster response, we
recommend a 60 Hz internal data rate where the line frequency is 
60 HZ, and a 50 Hz rate where the line frequency is 50 HZ. 

2) Remote averaging will increase the filtering, but will slow the 
scanning rate. To get the smoothest data with the smallest data
files, increase remote averaging to the largest value that will
allow you to scan fast enough. See #4 below for scan rate. 

3) Click SETUP to change the selected active channels. The 16 input 
channels for the standard EMF16 are shown in the column labeled "0" 
on the left. The selected active channels must be in a continuous 
sequence. 

***
4) Scan types: 

  Normal scanning is a compromise between maximum speed and stability.
  It is often preferred for electrochemistry applications.

  Calibration scan adds two extra channels to each scan and
  corrects for offset drift. You may want to use some local
  averaging with a caibration scan to keep the offset correction
  from adding marginally to the noise. The offset drift is expected 
  to be less than 100 microvolts per degree C, so this correction 
  may be unnecessary in many applications. 

Single-channel scanning allows much higher scan rates on one channel at 
  a time. The maximum scan rate is normally much slower than the data rate. 
  In Single-channel scan mode the two rates are  nearly the same. The scan 
  must be stopped before a different single channel can be selected.  

5) The minimum achievable scan interval will be automatically selected.
If you wish to scan more slowly, enter the desired (larger) interval.

6) Click CLOSE to return to the graphics screen.   


C) Graphics Set Up

1) Up to 16 Channels can be plotted at the same time on the single
set of axes.

2) Channels to plot can be selected from among the active sub-channels
for any particular input channel. For the standard EMF16, the "MAIN" 
channel should always be set to 1.

***
3) Adding or removing a channel from the plot does not change the 
scanning sequence or the data logging files. It does change the
Autoscaling. Left or right mouse buttons can be used when
changing channels to graph. The left button will select or de-select
intervening channels. The right button toggles only one channel at
a time.

4) You can set the plus and minus full scale values by directly typing 
the voltage desired and pressing Enter, or use Autoscale. The horizontal 
axis timebase can also be changed directly in the same fashion.

5) Click the Text Screen/Graph Screen button to toggle between the
two presentations.


D) Offsets

1) Each EMF16 channel has its own small offset associated. To
remove these offsets, begin a scan with all inputs active and
electrically shorted using the plugs provided. Put the ground 
switch in the SAFE position. Best results will be obtained with
remote averaging set at 8 or above. After a few minutes, click 
Save offsets. That will force all readings at that time to be 
zero. 

2) Thereafter, those offset corrections will be stored and used
each time you start your software. If you want to redo the
offsets, click Save Offsets again. 

NOTICE: If you save offsets inadvertently, or with floating channels,
subsequent data may be drastically shifted.

3) To permanently remove all saved software offset corrections, click 
Reset Offsets.


E) Other Functions 
 
1) Check the LOG box to save data to disk. The Data files are placed in 
the working directory and are named using the date and time. Click the
box again to stop the data logging. A new file is created for each 
Start Scan. Checking and unchecking the Log box during a scan will
result in gaps in your log file. Note that the first column in the file 
is the time stamp. 

2) BAUD can normally be left at 9600. If serial errors occur, or
sign on is troublesome, switching to 4800 BAUD will likely fix it. 

3) Gain can be set in powers of 2. The input range is cut in half
for each increase in gain. Normal gain is 1 for a range of +/- 5 volts.
A gain of 2 gives a range of +/- 2.5 volts, 4 gives +/- 1.25 volts, etc.
Scanning must be stopped in order to change the gain.

***
4) Local Average is a running average calculated in the host computer.
The average array is pre-loaded with the voltages from the first 
scan. For large averaging values and/or wide scans, you may see a 
message on your screen that indicates the arrays are being initialized. 
The textual data on your screen, the graph, and the data files all
reflect the averaged values.


