Perform a Tilt Test to check the integrity of the Quartz Bourdon Tube (QBT) sensor.
Ensure that the controller (or monitor) is in the MECHANICAL ZERO screen by this path, MENU||CALIBRATE||ZERO|MECHANICAL ZERO
1. Document the reading
2. Lift the left side up with a 1 to 2 inch (2.5 to 5 cm) block. Wait a few seconds for the reading to settle. Document the reading.
3. Lift the right side up with a 1 to 2 inch (2.5 to 5 cm) block. Wait a few seconds for the reading to settle. Document the reading.
The yellow bar on the display should move, then return to approximately the same value as reading #1 with each tilt. After each tilt, if you see a significant difference in readings from reading #1 (for example >30% change in value) report the values back to Pressure Technical Support as this may be a sign of a damaged sensor.
The official specification on the tilt sensitivity is <= 0.002% FS/degree. These controllers are 16.25 inches wide so a 1 inch block causes a 3.5% angle. A 2 inch block causes a 7% angle.
Also verify that the power-on self-check passes. You can also do this self-test in the TEST screen.
Here is the same test with specifications
- Change the units on the front panel to “% FS” instead of kPa, Bar, psi,etc.
- Zero the unit through the front panel <Menu>, <Calibrate>, choose sensor, <Zero>.
- Place a ½ inch (1 cm) spacer under the front and back feet on the right side. When the reading stabilizes, it should be less than 0.0010%FS.
- Move the spacers to the front feet of the unit (left and right side). When the reading stabilizes, it should be less than 0.0010%FS.
A link to the same information in a pdf file is below.
The mechanical zero tool information is here if one is needed. Photo with scissors shows how big it is. Note that the torque spec for the fixing bolt is 12 to 15 in-lb (not very tight). Over-tightening can bend the bracket and cause bigger issues.
Part Number: 3878975
Description: 7250-111,TOOL, PHOTOCELL ADJUST
Parts can quoted or ordered by emailing orders@flukecal.com or calling +1-877-355-3225