How to use a dial indicator with a double cable tray

A dial indicator can be used to measure alignment, level, and spacing of a double cable tray by securely mounting it, zeroing the dial, and taking precise readings along the tray surfaces.

Step 1: Prepare the Dial Indicator

Ensure your dial indicator is clean, calibrated, and functioning properly. Check that the plunger moves freely and the dial reads zero when not in contact with any surface . Select a magnetic base or clamp that can securely attach to a stable surface near the cable tray.

Step 2: Mount the Indicator

Attach the dial indicator to a magnetic base or adjustable stand. Position it so the plunger contacts the surface of the cable tray you want to measure. For a double cable tray, you may need to measure both trays individually or simultaneously if the indicator can reach both surfaces . Ensure the plunger is perpendicular to the tray surface for accurate readings.

Step 3: Zero the Dial

Rotate the bezel to set the dial to zero at your reference point. This establishes a baseline for measuring deviations in alignment, height, or spacing between the trays . For multiple points along the tray, you may need to reset zero at each reference location.

Step 4: Take Measurements

Move along the cable tray, gently pressing the plunger against the surface at each measurement point. Record the dial readings to detect any misalignment, unevenness, or spacing variations between the two trays . Positive or negative readings indicate deviations from the reference plane.

Step 5: Analyze and Adjust

Compare the readings across the tray length. If deviations exceed acceptable tolerances, adjust the tray supports or brackets to achieve proper alignment and level. Repeat measurements after adjustments to confirm accuracy .

Tips for Accuracy

• Ensure the tray surfaces are clean and free of debris before measuring .
• Always read the dial at eye level to avoid parallax errors.
• Use multiple measurement points along the tray for a comprehensive assessment.
• Regularly check the dial indicator calibration to maintain precision. By following these steps, a dial indicator can effectively ensure that a double cable tray is properly aligned, level, and spaced, improving installation quality and reducing potential issues with cable management.