Meilhaus Electronic redlab 1208fs, User Manual

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RedLab 1208FS User's Guide Functional Details
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RedLab 1208FS channel gain queue feature
The RedLab 1208FS's channel gain queue feature allows you to set up a scan sequence with a unique per-
channel gain setting and channel sequence.
The channel gain queue feature removes the restriction of using an ascending channel sequence at a fixed gain.
This feature creates a channel list which is written to local memory on the RedLab 1208FS. The channel list is
made up of a channel number and range setting. An example of a four-element list is shown in the table below.
Sample channel gain queue list
Element Channel Range
0 CH0 BIP10V
1 CH0 BIP5V
2 CH7 BIP10V
3 CH2 BIP1V
When a scan begins with the gain queue enabled, the RedLab 1208FS reads the first element, sets the
appropriate channel number and range, and then acquires a sample. The properties of the next element are then
retrieved, and another sample is acquired. This sequence continues until all elements in the gain queue have
been selected. When the end of the channel list is detected, the sequence returns to the first element in the list.
This sequence repeats until the specified number of samples is gathered. You must carefully match the gain to
the expected voltage range on the associated channel
— otherwise, an over range condition can occur. Although
this condition does not damage the RedLab 1208FS, it does produce a useless full-scale reading. It can also
introduce a long recovery time from saturation, which can affect the next measurement in the queue.
Synchronizing multiple units
You can connect the SYNC pin of two RedLab 1208FS units together in a master/slave configuration and
acquire data from the analog inputs of both devices using one clock. When the SYNC pin is configured as an
output, the internal A/D pacer clock is sent to the screw terminal. You can use this signal as a clock input to a
second USB by connecting it to the SYNC pin of the second USB.
When used as a clock input, the SYNC pin operates in one of two modes – Continuous or Gated .
In the default Continuous mode, a RedLab 1208FS ignores the first clock pulse in order to ensure adequate
setup time. Use this mode if the unit is being paced from a continuous clock source, such as a generator.
In the Gated mode, it is assumed that the clock signal will be held off for an adequate amount of time for setup
to occur. No clock pulses are ignored. Use this mode if the RedLab 1208FS is set up as a slave and the source of
the external clock is another USB.
The SYNC pin (pin 19) is set for pacer output by default. To synchronize a master RedLab 1208FS with a slave
RedLab 1208FS and acquire data, follow the steps below.
Article I. Connect the SYNC pin of the master RedLab 1208FS to the SYNC pin of the slave RedLab
1208FS.
Article II. Run InstaCal.
Article III. From the
PC Board List
on the
InstaCal
main form, double-click on the RedLab 1208FS you
want to use as a slave. The
Board Configuration
dialog opens.
Article IV. Select Gated from the
Ext. Clock Type
drop-down list.