DMS Go Operator&#39

Chapter 2. Instrument Setup

2.4.2 Configuring the Instrument

Three instrument settings are directly dependent on the type of probe installed. These settings must be adjusted any time a probe of a different type is installed, by following the instructions in the following sections.

2.4.2a Determining the Probe Type (PROBE & CAL - PROBE)

1.

Activate the

PROBE & CAL submenu using the joystick (

).

2.

If the DMS Go is connected to a dialog probe, it automatically detects the probe if the probe selection is on a dual element probe. Once detected, the screen shows the word “Dialog” below the probe name. If it is not a dialog probe, use the joystick to scroll through the list of probes and select the appropriate unit. (If you disconnect a dialog probe, then the DMS Go displays the last probe selection, but the dialog below the probe will no longer appear.) If you change a non-dialog probe, you must again scroll through the list and select the new unit.

Note: A dialog probe contains a small chip with probe information. When the probe is connected to the DMS Go, it transmits this

information to the unit.

Note: The DMS Go offers an option for a GE-supplied custom probe definition file, with a .prb suffix, to be entered via the SD card. The

DMS Go will show this file as part of the Probes list, designated by the (Custom) addition.

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2.4.2a Determining the Probe Type (PROBE & CAL - PROBE)

Chapter 2. Instrument Setup

3.

Move the joystick up or down (

DMS Go Operator’s Manual

Figure 21: Display for Connected Dialog Probe

(Dialog Indicated by Signal at Bottom)

) to navigate away from this function, or press HOME to return to the Main Menu.

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Chapter 2. Instrument Setup

2.4.2b Setting the Ultrasonic Detection Mode (PROBE & CAL - TG MODE)

The DMS Go performs all measurements in zero-crossing mode, at the point where the signal crosses the zero amplitude line. The available modes will vary with the probe used.

IMPORTANT: Not all modes are available for all probes!

1.

In the

MAIN menu, scroll to the PROBE & CAL submenu using the joystick (

).

2.

Use the joystick ( ) to select the function titled

TG MODE, and then to select the mode. Six options are available:

•

S-IP — This mode indicates that a single-element type transducer is connected to the DMS Go. It starts ultrasonic detection from an artificial point relative to the pulser firing (IP, initial pulse, or “T0”) and ends with the last zero crossing before the first detected flank crossing in gate-A. The corresponding TOF is compensated by the probe zero offset (P-delay), calculated automatically during the calibration process. The DMS Go calculates and displays a thickness result value from the acquired data. It is used with a single-element probe to test thickness in non-coated materials, especially those with smooth, parallel surfaces.

•

S-PEAK — This mode indicates that a single-element type transducer is connected to the DMS Go. It starts ultrasonic detection from the last zero crossing before the peak in gate A and ends with the last zero crossing before the peak echo in gate-B. The DMS Go calculates and displays a thickness result value from the acquired data. It is used with a single-element probe to test thickness in coated materials, especially those with smooth, parallel surfaces.

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Chapter 2. Instrument Setup

2.4.2b Setting the Ultrasonic Detection Mode (CONFIG - TG MODE) (cont.)

•

S-FLANK — This mode indicates that a single-element type transducer is connected to the DMS Go. It starts ultrasonic detection from the last zero crossing before the first detected flank in gate-A and ends with the last zero crossing before the first detected flank crossing in gate-B. The DMS Go calculates and displays a thickness result value from the acquired data. The mode is used with a single-element probe to test thickness in COATED materials, especially those with smooth, parallel surfaces.

•

DUAL — This mode indicates that a dual-element type transducer is connected to the DMS Go. It starts ultrasonic detection from an artificial point relative to the pulser firing (IP, initial pulse, or “T0”) and ends with the last zero crossing before the first detected flank in gate-A. The corresponding TOF is compensated by the probe zero offset (P-delay), calculated automatically during the calibration process. The DMS Go calculates and displays a thickness result value from the acquired data. This mode is used with a dual-element probe to test corrosion thickness in non-coated materials, especially on curved and irregular backwall surfaces.

•

DUAL-MULTI — This mode is available when a dual-element type transducer is connected to the DMS Go. It starts ultrasonic detection from the last zero crossing before a peak echo detected in gate-A and ends with the last zero crossing before a peak echo in gate-B. The DMS Go calculates and displays a thickness result value from the acquired data. This mode is used with a dual-element probe to test thickness in coated materials.

•

TOP-COAT—When used with a special TopCOAT probe, this mode tests thickness in coated materials. It is especially well suited to curved and irregular (pitted) backwall surfaces. (Optional)

•

AUTO-V— When used with a special TopCOAT probe, this mode measures non-coated materials. It requires no knowledge of the measured material’s type and calculates velocity without a like-material calibration standard. (Optional)

DMS Go Operator’s Manual 59

Chapter 2. Instrument Setup

2.4.2b Setting the Ultrasonic Detection Mode (CONFIG - TG MODE) (cont.)

3.

After making your choice, use the joystick ( ) to move to another function, or press HOME to return to the Main Menu.

2.4.2c Setting the Thickness Calibration Method (PROBE & CAL - THK CAL)

In this option, you can set thickness calibration to one or two points.

1.

In the

MAIN menu, scroll to the PROBE & CAL submenu using the joystick (

).

2.

Use the joystick (

2-point.

) to select the function titled

THK CAL, and then to select the method. The available choices are 1-point and

3.

After making your choice, use the joystick ( ) to move to another function, or press HOME to return to the Main Menu.

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