Note: according to a customer this is how the switches are set as they are attempting a file transfer at 115200 BAUD.

Connect the G-857 to the computer using the download cable and a properly installed USB/RS-232 adaptor. (Must have FTDI):

Open the MagMap Software.

Select Import>G-857/ASCII

1. Enter known Serial Port (My computer is COM4)

2. BAUD 115200 (Switches 6, 7 and 8 off)

3. Set a good location for the file to written to.

4. Leave Download only, open later unchecked.

5. Leave download time out 2.

Select OK.

On the G-857 press OUTPUT, ENTER when this window opens.

BYTES DOWNLOADED will begin to increment.

Select OK in the window below:

The downloaded Mag file should be displayed:

If the download sequence does not happen this way, it is usually a problem with:

1. USB/RS-232 Adaptor not FTDI, or driver not installed.

2. COM PORT assignment incorrect, and/or file destination not valid.

3. BAUD RATE mismatch.

4. Faulty I/O Cable PN 16492-01.

5. Faulty Computer.

6. Faulty G-857 console.

Check to make sure that the G-857 is not in Legacy Mode:

To check if Legacy Mode is enabled press:

AUTO-OUTPUT

To turn it off press:

AUTO-OUTPUT-CLEAR

To Turn on:

AUTO-OUTPUT-ENTER

If Legacy Mode was on then the recorded data recorded needs to be downloaded as a G-856:

The batteries should be charged using the charger furnished with the instrument. These chargers are fully automatic and designed to do the best job of charging and maintaining the batteries for long life. All of the chargers are equipped with lights indicating when the battery is being charged and when the charging cycle is completed.

The battery packs will provide the most operating cycles when they are fully charged after each use. The number of operating cycles can vary from 250 cycles to above 1000 cycles depending on how deep the discharge was and how soon the battery is charged after use.

A 30% discharge per cycle may result in a lifetime of 1000 cycles or more, whereas a 100% discharge per cycle can result in only 250 cycles. As a rule the magnetometer will shut down when the battery is discharged to about 20% of full voltage. This is to ensure proper shutdown of the instrument.

It is very important to recharge the battery as soon as possible after use so the maximum life can be expected from the pack. If the discharged pack is left to charge “when we get back from the field” the pack can suffer from “sulphation”. This is a high-resistance buildup in the battery which may render the battery unusable.

If a battery of this type must be stored for an extended period, it must be stored in a fully-charged condition. If such a battery is stored discharged and subject to below-freezing conditions, it is likely to freeze and be subsequently unusable.

All Lead-Acid batteries must be maintained when in storage. This means that the user must recharge each pack at least once a month. Lead Acid batteries will self-discharge due to stray internal resistances, causing very small drain currents. Thus the maintenance requirement for monthly recharging is critical to long battery life. Do not leave the charger on all the time during storage. Also it is very important to use discharge the batteries on a regular basis otherwise the lifespan will be severely shortened. For more information contact our Support Department.

1. n-Decane
2. Shell Sol-71 (Shell oil product)
3. Isopar-G (Exxon oil Co.)
4. Odorless mineral sprits (Naptha)
5. Mineral Spirits (Naptha)
6. Charcoal Lighter Fluid
7. Kerosene lamp oil
8. Kerosene
9. Mineral Oil (medicinal Grade)
10. Diesel Fuel (may degrade diaphragm on marine systems)
11. Camp Stove fuel
12. White Gas
13. Unleaded gas

The preferred fluids are items 1-7 above.

Items 3 & 4 are not the same as paint thinner. Paint thinner will damage the sensor coils, as will Acetone, and should not be used.

Items 11 - 13 have a very low flash point and should be used with extra caution, although any petroleum product must be handled carefully.

There are several Alcohols which will produce an acceptable signal, but will tend to absorb water. This will degrade the performance of the sensor over time. These should be replaced as soon as possible with an alternate fluid from the above list.

Usable alcohols:

1. Ethanol (Grain Alcohol) at least 190 proof
2. Methanol (wood alcohol)
3. Denatured Alcohol (ethanol made poisonous)

All of these fluids must be as clean as possible to ensure that no water or contaminates (rust) are in them. Use a filter to make sure the fluids do not contain rust from the storage container.