A27 Wedge Method

Definition

Sets the transducer mounting method. The method determines the ultrasonic path through the pipe, and therefore the spacing of the two transducers will be shown in A29 Probe Spacing.

Choose Probe Installation Method (Click to expand)

Choose Probe Installation Method (V/Z)

Select the mounting geometry before fixing the bracket — this determines how the two TM-1 transducers are positioned relative to each other, and must be entered later as A27 Wedge Method in Parameter Settings.

Pipe Size	Method
2" or smaller than 3"	V
3"–8"	V or Z — either works
8"-16"	Z

• V configuration: both transducers mount on the same side of the pipe. The ultrasonic signal reflects once (a "V"-shaped bounce). Because both transducers are on the same side, probe spacing is easier to measure, and the single reflection gives a balanced signal strength.

• Z configuration: transducers mount diagonally on opposite sides of the pipe. The signal travels direct and unreflected, which keeps signal strength strong — useful for high-interference fluids (bubbles, impurities, scale buildup). Because the transducers are on opposite sides, measuring probe spacing is more difficult.

• For 3"–8" pipe, choosing between V and Z: choose Z if both sides of the pipe are reachable and you want maximum signal strength; choose V if only one side is accessible, or for easier installation.

Notes

1. Set A27 before installing the transducers — the required spacing in A29 depends on it.

2. After changing A27, re-run Z03 Auto Initialization and Z04 Auto Zero Offset.

Operation Procedure

Button Functions (Click to Expand)

When the main screen is displayed in green backlight, the four buttons function as follows:

• Blue Button (leftmost): Return, exit, or save settings.

• Gray Direction Buttons:

  • Left Gray: Previous Page, decrease value, or select item

  • Right Gray: Next Page, increase value, or select item

• Orange Button (rightmost): Rightmost button: Enter settings, edit, or confirm selection

Do not hold buttons for extended periods to avoid damage.

Button functions may change depending on the operation context to improve usability or prevent accidental presses.

A27 Wedge Method Setting Steps
• From the main screen (green backlight), press Orange Button (Setup) to enter settings (orange backlight).
• Use Gray Arrow Buttons to select A. Measure, press Orange Button (Enter).
• Use Gray Arrow Buttons to select A27 Wedge Method, press Orange Button (Enter).
• Use Gray Arrow Buttons to choose the mounting method.
• Press Orange Button (Set) to confirm.
• Press Blue Button (ESC) to return to the main screen (green backlight).

A27 Options, RS485 Values, Read/Write Commands, and Formats

Options	Description	RS-485 value
Z	Single pass, opposite sides	0
V (Default)	Double pass, same side	1
N	Triple pass, same side	2
W	Quadruple pass, same side	3

Refer to the Read/Write Memory List for the Modbus command format. This parameter uses the Int16 data format.