Omega Engineering OMB-DBK-34A, User Manual

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Each DBK8 channel has 3 user-set voltage ranges: ±10 V, ±50 V, and ±100 V. The ranges are selected by
the placement of shunt jumpers on pin headers for each channel. While the channel-to-channel resistance
is 10 M
Ω
, there is no other inherent isolation between the channels. The common of the host computer has
a direct connection to the LogBook or the Daq Device analog common. Either side of any input channel is
5 M
Ω
from analog common.
The DBK8 has 3 attenuation factors.
•
The ±100 V range attenuates the input by a factor of 20.
•
The ±50 V range attenuates the input by a factor of 10.
•
The ±10 V range attenuates the input by a factor of 2.
Note : The signal coming from the DBK8 into the LogBook or Daq Device does not exceed ±5 V.
Hardware Setup
Card Configuration
Factory Defaults:
Voltage Range (each channel) - ±10V
Inputs from 1 or 2 DBK8s are multiplexed into 1 of the base channels.
Channel selection is made on 2×16-pin header JP1A by placing the shunt
jumper on the pair of pins next to the chosen base channel.
DBK8, pg. 2
888194
DBK Option Cards and Modules
The addressing scheme allows for 16 inputs on each analog channel. The
DBK8 is an 8-input card; and 2 DBK8’s can use the same channel if one
is configure for low channels and the other for high channels. Placing the
shunt jumper on JP16 in the 2-1 position sets the card address for the
lower 8 channels (0-7) in an address group. Placing the shunt jumper on
JP16 in the 2-3 position sets the card address for the upper 8 channels (8-
15).
Each of the 8 input channels has 3 voltage ranges that are manually
selected by the placement of a pair of shunt jumpers on a channel range
select header. It is important that both jumpers are placed on the same
range value or incorrect voltage readings will be received by the system.
Card Connection
The DBK8 is equipped with screw terminal connectors for easy access to
all of the analog inputs. Connections are provided for 8 pairs of inputs
and 2 analog-commons. There is a high and a low terminal in each
channel pair to maintain consistent polarity signs with voltage readings. For AC signals, the polarity is
arbitrary unless multiple signals are being connected
with an interest in channel-to-channel phase relationships. After all connections
are in place, captive areas are provided at the end of the DBK8 for securing the
wires to the board. Nylon tie wraps (not included) work well for this purpose.
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.