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4. TAKING READINGS
4.1 GK-404 Readout Box
The Model GK-404 Vibrating Wire Readout is a portable, low-power, handheld unit that can run
continuously for more than 20 hours on two AA batteries. It is designed for the readout of all
Geokon vibrating wire gauges and transducers; and is capable of displaying the reading in either
digits, frequency (Hz), period (µs), or microstrain (µε). The GK-404 also displays the
temperature of the transducer (embedded thermistor) with a resolution of 0.1 °C.
Before use, attach the flying leads to the GK-404 by aligning the red circle on the silver “Lemo”
connector of the flying leads with the red line on the top of the GK-404 (Figure 7). Insert the
Lemo connector into the GK-404 until it locks into place.
Figure 7 - Lemo Connector to GK-404
Connect each of the clips on the leads to the matching colors of the sensor conductors, with blue
representing the shield (bare). To turn the GK-404 on, press the “ON/OFF” button on the front
panel of the unit. The initial startup screen will be displayed. After approximately one second,
the GK-404 will start taking readings and display them based on the settings of the POS and
MODE buttons.
The unit display (from left to right) is as follows:
•
The current Position: Set by the
POS
button, displayed as a letter A through F.
•
The current Reading: Set by the
MODE
button, displayed as a numeric value followed by the
unit of measure.
•
Temperature reading of the attached gauge in degrees Celsius.
Use the
POS
button to select position
B
and the
MODE
button to select
Dg
(digits). (Other
functions can be selected as described in the GK-404 Manual.)
The GK-404 will continue to take measurements and display readings until the unit is turned off,
either manually, or if enabled, by the Auto-Off timer. If no reading displays or the reading is
unstable, consult Section 6 for troubleshooting suggestions.
For further information, please refer to the GK-404 manual.