Measurement Computing DBK Part 2 - Manual (Page 27)

DBK Option Cards and Module 899892 DBK43A & DBK43B, pg. 7
The Kelvin connection using the remote sensing lines performs best when the entire bridge is localized
(no bridge-completion resistors inside the DBK43A or DBK43B) and all leads are contained in a multi-
conductor cable. If individual wire leads are used, the two sense wires should be tightly twisted to form a
pair. Likewise, the two excitation wires and the two bridge-output wires should be twisted together).
The internal excitation source is attached to a voltage regulator in the strain gage module’s circuitry. The
regulator provides the excitation to the actual transducer (there is a separate regulator for each transducer,
hence 8 regulators per strain gage module). Each regulator has a maximum current of 50 mA. The
maximum excitation voltage that can be provided by the module’s excitation regulator is:
V
MAX[EXC]
= 0.05 × R (where R = the resistance in ohms of 1 element in the bridge circuit) .
CAUTION
Setting the excitation voltage above the maximum voltage allowed can cause the
DBK43A or DBK43B to fail. The maximum allowable excitation voltage is determined
by the following equation.
V
MAX[EXC]
= 0.05 x R
R is the resistance in ohms of 1 element in the bridge circuit.
The following full-page figure shows various strain-gage configurations.