Omega Engineering OMB-DBK-34A, User Manual

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Current Level (Transducer Biasing) (JP6)
Current level is not channel-specific. The level selected applies to
both channels. The figure shows the JP6 jumper settings for
current level. Most transducers operate with either 2 or 4 mA of
bias current. However, biasing at 4 mA allows the transducer to
drive longer cables.
Reference Note :
For more information, refer to the Cable Driving section of the DBK4 A ccelerometer Tutorial .
Filter Bypass (JP7 & JP8)
Jumpers JP7 and JP8 are used to enable or disable programmable
filtering for channel 0 and 1 respectively. This selection determines
the bandwidth of the signal to be processed. When disabled
(bypassed) the DBK4 can process a signal with a bandwidth up to 40
kHz. The gain in bypass mode is greater than in the filter mode by a
factor of 1.583. For example, When the PGA gain is set to 10, the
filter-mode gain is ×10 and the bypass-mode gain is ×15.83.
DBK4 Channel Hierarchy
Main Channel and Sub Channel Selection
Up to 8 DBK4 cards can use 1 of 16 main channels.
Each DBK4 has 2 inputs; thus the input capacity is
256 channels (2 inputs × 8 cards × 16 main channels).
The DBK4 uses JP1 and SW1 for channel and sub-
channel selection. (Position s8 on SW1 is not used.)
The DBK4 card or a group of DBK4 cards (0-7) must
have a dedicated main channel. Do not intermix
DBK4 cards with other types of DBK cards in a
channel. LogBook or Daq device will not function
properly if channel settings are in conflict.
Record all channel settings and label the transducers for future reference.
JP1 on the DBK4 is a 2×16 header located on the far left side of the card. A shunt jumper setting on JP1
allows a card to reside in 1 of 16 possible main channels. Any main channel in the range 0-15 is valid.
The figure below shows that sub-switches s1 to s4 of SW1 can be set by binary values to equal the main
channel selection. This setting must match the jumper on JP1 so the onboard microcontroller knows the
JP1 selection. The card then interprets and responds to only the correct card-related commands via P1.
DBK Option Cards and Modules
958293
DBK4, pg. 5