4-7.2.15 Ballast tank liquid level Indicator
4-220.127.116.11 Cleaning and inspection
Make sure equipment monitoring system is off before starting cleaning and
Clean tank liquid level indicator connections and equipment monitoring system connections by vacuuming
or cleaning with electrician's brush.
Visually inspect for corrosion, loose connections, or damaged wiring. Clean corrosion, tighten loose
connections, and replace damaged wiring.
Make sure equipment monitoring system is off before performing continuity check.
Check continuity between sensor and monitoring system main processor. If continuity test indicates a
closed circuit, perform sensor test in steps b thru e. If continuity test indicates an open circuit, clean,
inspect, and repair as given in paragraph 4-18.104.22.168.
Storage tank liquid level indicator test is to be performed using the equipment
discussed in TM 55-1930-209-14 & P-11. This procedure is to be used when sensor
readings are onscale and stable but are inaccurate.
Check level indicated on visual flag level indicator. If level does not agree with monitor display page
(Figure 3-3), go to step c.
Check that the following span reference value as shown on Drawing 23285 in Appendix B and the value
for drinking water tanks shown on the edit page agree.
Calibrate sensor by calculating new offset using the following equation:
(Actual Reading - Displayed Reading) x 3840
+ Old Offset