GTJ-4114 Electrical Density Gauge (EDG)
Introduction
Your Electrical Density Gauge (EDG) is capable of providing accurate readings of soil density, moisture content, and percent compaction on soils typically used for roads and foundations. The precision by which the EDG can determine these physical parameters depends highly upon you, the operator. Reading and understanding the contents of this manual is a very important step toward utilizing EDG to its maximum potential. Please review the packing list of items that constitute the complete EDG, and that were shipped to you. If there is any doubt as to whether you received the complete set of items, please contact the factory immediately. The following will give you an overview of the EDG process and help you understanding the more detailed steps found later in the manual.
Is EDG Safe To Use?
Absolutely! There is far less measuring energy present when using EDG than when you are using a cell phone.
Introduction to the EDG Process
The EDG process introduces some new terminology with which you need to be familiar. A Soil Model is a combination of electrical soil data and user-entered physical soil data. The Soil Model provides the basis for testing a specific soil type within an area of similar soil characteristics.
To make a Soil Model, several electrical signatures are acquired using the EDG at different Test Spots (the Test Spots for a Soil Model are called Soil Tests).For each Test Spot that an electrical signature is acquired, a Sand Cone test is also performed to obtain physical wet density, dry density, and percent moisture information. A proctor test can optionally be performed to determine the maximum dry density. The physical information determined by the Sand Cone and Proctor Mold laboratory tests are entered into the EDG unit, thereby tying electrical signature information to physical data.
At least three Test Spots (Soil Tests) are required to create a Soil Model; more Test Spots make for a more representative Soil Model. Further, Test Spots that exhibit a broad range of density and moisture content make for more accurate Soil Models.
Once the Soil Model has been created, the EDG is ready for testing at a Job Site. A Job Site is an area of similar soil characteristics in which the user wishes to determine the physical characteristics of the soil.
A single Soil Model is generally created for each different Job Site. Once a Soil Model has been created that accurately models the Job Site, the soil characteristics of any Test Spot within the Job Site can be accurately and quickly determined by the EDG by performing a Field Test.
A Field Test is electrical soil data at a particular Test Spot that is fed into the Soil Model to produce physical soil characteristics.
Components of the EDG Unit
EDG Console/Computer, Electrical Soil Measurement Sensor, Dart Template, Hammer, Cables/Clips for Soil Measurement Sensor, Soil Darts, Battery Charger, Temperature Probe, Break-Out Cable.
Components:
EDG Console/Computer:
The EDG unit contains a computer that applies mathematical formulas to determine the physical characteristics of the soil. The computer also contains memory that remains intact after the EDG has been powered off; this memory is used to save Soil Models and Job Site data. The EDG console has an LCD display that is used to provide visual information to the user and a keypad that allows the user to key information into the EDG unit.
Soil Electrical Measurement Sensor:
The Soil Sensor is connected to the Soil Darts and EDG Computer using cables and clips. Then the Soil Sensor gathers electrical information about the soil under test and transfers the information to the EDG computer. The Soil Sensor requires no maintenance or adjustment, so there is no need to open the enclosure. Keep it clean and dry when using it. It is an electronic circuit, so treat it with the same respect you use with your cell phone. If the Sensor Pins become loose, hold the pin with pliers while tightening the nut against the enclosure.
Soil Darts:
To get electrical data from the soil, 4 Soil Darts are pounded into the ground with a hammer. A template is provided to accurately position the Soil Darts. The Soil Darts are machined from stainless steel, and are expected to last many years. If the conical end becomes flattened from hitting too many rocks, either file or grind off any mushrooming at the point to maintain a conical shape to the Dart. If the top end of the Dart becomes damaged or starts to crack from excessive hammering, file off the damaged part to avoid having pieces of steel flying off when driving in the Dart. Always wear safety glasses when hammering in the Soil Darts.
Temperature Probe:
Temperature Probe: The temperature probe attaches to the right panel receptacle. When performing EDG testing, the temperature probe should be placed into the soil. The soil temperature is an important variable in accurate EDG testing. The EDG computer uses the temperature information to perform temperature compensation, resulting in more accurate EDG results. The temperature probe must be connected when creating Soil Models; use of the temperature probe is optional when performing Field Testing. If the temperature probe is not used during Field Testing, the EDG results cannot be temperature compensated.
EDG Battery/Battery Charger:
The EDG battery is rated at a capacity of 4.0 Amp-Hours. This is enough energy for continuous operation for over 8 hours. The Battery Charger that is provided with EDG will charge the battery in approximately 14 hours. Therefore, EDG should be placed on charge each day after use, and be allowed to charge overnight. The battery will not be overcharged if left on charge for a two day weekend period. As noted above, the Temperature Probe must be removed and the Break-Out Cable attached to charge the battery.
The Break-Out Cable:
The Break-Out Cable provides a USB connector for connection to a host PC for use in Data Sharing mode.
Technical parameters:
| Name |
Soil Non-nuclear Electrical Density Gauge (EDG) |
| Model |
GTJ-4114 |
| EDG host and connector |
Waterproof connection |
| Wet density range |
According to typical compacted soil dry density accuracy: within 3% of standard physical tests |
| Moisture content range |
According to the accuracy of typical compacted soil moisture content: within 3% of standard physical tests |
| Maximum RS-232 cable length |
100cm |
| Internal power supply |
12V nickel hydrogen, 2000mAh capacity |
| Battery life |
About 24 hours |
| Operating temperature range |
0~50ºC |
| Operating humidity range |
5%~90% |
| EDG controller weight |
8kg |
| EDG controller size |
300*260*140mm |
| EDG accessories weight |
About 3kg |
| Box size(mm)/weight (kg) |
480*215*390mm/8.5kg |
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