small electrical logging tool

Well Pack10
Specifications/Instructions

Geo Tec Service Co., Ltd.
〒950-0951 4-7-22 Toyano, Chuo-ku, Niigata City
TEL +81-25-282-3246
FAX +81-25-284-0144
Email: info@geots.co.jp

First edition: 2008/07/01
Update date: 2023/05/19

1. Overview
This machine is a compact and lightweight electrical logging and resistivity measuring instrument for welldrilling sites.

2. Specification
2.1 Measurement method
Method: constant current pulse drive type, four-terminal measurement
Measured value display: Max. 1999 display
Measurement range switching : automatic
Measurement waveform: square wave constant current control Max 15Vp-p
Measurement frequency: 10Hz

2.2 Output current, voltage and resistance measurement range
This unit automatically determines the output current and input voltage range according to the conditionsof the object to be measured, and measures the resistance value.
Relationship between resistance measurement range and device output current and input voltage range
output current /input voltage range

0.2mA

1mA

5mA

25mA

0.1V

～500Ω

～100.0Ω～20.0Ω

～4.00Ω

1V～5.00KΩ

～1000Ω

～200Ω

～40.0Ω

10V～50.0KΩ

～10KΩ

～2.00KΩ

～320Ω

2.3 Power supply
Power supply voltage: DC 6V ( 4 AA-batteries)
Current consumption:
about 180mA (measured current 25mA, battery voltage 6V)
about 110mA (measured current 0.2mA, battery voltage 6V)
Continuous use time: 6 hours to 10 hours using alkaline batteries

2.4 Others
Operating temperature and humidity: 0-50°C, 80RH% or less (no condensation)
Body dimensions: 160 (W) x 80 (D) x 55 (H) (dimensions not including protrusions)13. Equipment description① Power switch
Pushing it to the ON side turns on the power of this unit.
② Terminal for measurement
C1, C2: Constant current drive output terminals.
P1, P2: Voltage measurement terminals.

③ Operation indicator lamp
Displays the operating status of the machine.
POW: The power indicator lamp lights up when the unit is in operation.
LB : Low battery voltage warning lamp.
Flashes when the battery voltage drops during operation. Please replace the battery.
ER : This is an error display lamp.
If the measurement target exceeds the measurement range of this unit or due to incorrect
wiring, etc., normal measurement may not be possible. Flashes if it is not possible.

2

④ LCD liquid crystal display
Displays the current output current, input voltage range and resistance measurement.
In the case of a measurement error, the contents of the error are also displayed.
⑤ Battery compartment
The battery is housed in this part.
When replacing the battery, use a screwdriver to loosen the screws at the four corners of the main unit,
and the upper transparent cover will come off. There is a battery holder inside, so pull it out and replace
the battery.

4. How to connect the electrode selector switch
As shown in the figure below, connect the wires of electrode A (short) and electrode B (long) of theelectrical logging cable to the terminals.
Ｃ１

1.0ｍ
0.5ｍ

Ｃ１
Ｐ１

0.5ｍ

Ｐ１0 point position

0.25ｍ･ 0.25ｍ
Ｐ２
0.5ｍ

0.5ｍ
Ｐ２

Ｃ２

1.0ｍ

ＡＣ２B
8 wires
in total
４ wires

４ wires

Electrode selector switch

Short（electrode A）

Ｃ１ Ｃ１
Ｐ１ Ｐ１
Ｐ２ Ｐ２
Ｃ２ Ｃ２

【Note】
The well diameter(drilling diameter) is
200-400mm
then the electrode spacingis 0.5m and 1.0mLong（electrode B）

Ｃ１ Ｐ１ Ｐ２ Ｃ２

How to connect
the electrode selector switch

WELL PACK103