Geometrics Memory-Mag G-856AX, Руководство по эксплуатации

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Geometrics, Inc
.
G-856AX Operation Manual
36
At temperatures below 0° C, battery life decreases rapidly. At temperatures as low as
minus 20°C operation may be limited to only 100 readings per set of batteries. At such
low temperatures, a console that uses a rechargeable Gel-cell battery pack is preferable
but, regardless of battery type, the console should be held close to the operator's person
beneath the outer-most garment to take advantage of this insulation and the body heat of
the operator.
D-cells batteries
When the magnetometer is used as a base station, alkaline D-cell batteries will work
satisfactorily. Table 2 compares the expected number of readings expected for different
battery types. Note that an optional external sensor power cable is available for base
station use and it allows the user to connect the console to a 12v car battery. A typical
fully charged car battery will last many days and this power configuration is often used
when operating the G-856AX as a base station instrument.
When the G-856AX is used as a survey instrument, and is configured for operation from
D-cells, we recommend using cardboard or plastic jacketed batteries. If steel jacketed
batteries (carbon zinc or alkaline) are used in the console during survey operation a
directional dependent shift of several nT may result and this will bias the measurement.
Table 2. Battery endurance comparison.
Battery Type Brand Name
Number of
Readings @25°C
Number of
Readings @ 0°C
Jacket Type
Alkaline Burgess,
Eveready,
Duracell
6000 4000 Steel
Standard Carbon-
zinc (flashlight)
Burgess,
Eveready, Ray-O-
Vac.
1500 700 Cardboard
Premium Carbon-
zinc
Eveready #1250 3000 1700 Cardboard
Internal Gel-cell Power Sonic Full Memory
12000
Full Memory
12000
Plastic
The values shown in Table 2 correspond to one reading every 30 seconds, using the 3-
second cycle time setting (see Internal programming switches section in the Appendix).
Faster sampling rates will yield less endurance, especially at lower temperatures.
Photoflash and "Energizers" batteries are not designed for this type of application but
may be used until other batteries are available. Battery capacity decreases rapidly below
0°C for most battery types but Photoflash and “Energizers” will recover when warmed
above 0°C.