Examples of Bias Resistor Selection Options
Gain Settings
On the card, each channel has a gain-set switch and holes for gain resistors labeled
RG1 to RG4. The figure at the right shows gain values for switch settings 0 to 4,
with 0 being equal to x1 and 4 being equal to x500. If a custom gain is desired,
the switch is set to position 0 and a gain resistor must be mounted and soldered
onto the card. The value of the gain resistor is determined by the formula:
RGAIN = [40,000 / (Gain -1)] - 50 Ω
Address Configuration
As many as four DBK17s can be connected to each analog channel. With sixteen
channels (and four inputs per DBK17) 256 inputs are possible. Since this is a
daisy-chain interface, each card must have a unique address (channel and card
number). Note that the default setting for SW6 is Card 1.
To configure the card, locate the 16 × 2-pin header (labeled J1) near the front of
the board. The 16 jumper locations on this header are labeled CH0 through
CH15. Place the jumper on the channel you wish to use. Only one jumper is
used on a single card. Four cards in the daisy-chain can have the same channel
number as long as their card number is unique.
Set switch SW6 for each of four DBK17s on a single channel. Verify that only
one card in the system is set to a particular channel and card number.
CE Compliance
Reference Notes:
Should your data acquisition system need to comply with CE standards, refer to
the CE Compliance section of the Signal Management chapter.
DBK Option Cards and Modules 879895 DBK17, pg. 3