7
3. TAKING READINGS
The following three sections describe how to take readings using readout equipment
available from Geokon. Table 1 shows a 10,000 microstrain range gage, Other ranges are
avialbale on request.
Model:
4200ER - 10,000
Readout Position:
D
Display Units:
Readout units
Frequency Range:
400-1200 Hz
Mid-Range Reading:
2000
Minimum Reading:
1000
Maximum Reading:
3000
Table 1 - Embedment Strain Gage Readout Positions
3.1. Operation of the GK-403 Readout Box
The GK-403 can store gage readings and also apply calibration factors to convert readings
to engineering units. Consult the GK-403 Instruction Manual for additional information on
Mode "G" of the Readout. The GK-403 reads out the thermistor temperature directly in
degrees C.
Connect the Readout using the flying leads or in the case of a terminal station, with a
connector. The red and black clips are for the vibrating wire gage; the white and green
leads are for the thermistor and the blue for the shield drain wire.
1. Turn the display selector to position ""D".
2. Turn the unit on and a reading will appear in the front display window. The last digit
may change one or two digits while reading. Press the "Store" button to record the
value displayed. If the no reading displays or the reading is unstable see section 5
for troubleshooting suggestions. The thermistor will be read and displayed on the
screen above the gage reading in degrees centigrade.
3. The unit will automatically turn itself off after approximately 2 minutes to conserve
power.
3.2. Operation of the GK-404 Readout Box
The GK404 is a palm sized readout box which diplays the Vibrating wire value and the
temperature in degrees centigrade.
The GK-404 Vibrating Wire Readout arrives with a patch cord for connecting to the vibrating
wire gages. One end will consist of a 5-pin plug for connecting to the respective socket on
the bottom of the GK-404 enclosure. The other end will consist of 5 leads terminated with
alligator clips. Note the colors of the alligator clips are red, black, green, white and blue.
The colors represent the positive vibrating wire gage lead (red), negative vibrating wire gage
lead (black), positive thermistor lead (green), negative thermistor lead (white) and
transducer cable drain wire (blue). The clips should be connected to their respectively
colored leads from the vibrating wire gage cable.
Use the
POS
(Position) button to select position
D
and the
MODE
button to select
μ
E
