Kistler-Morse KM L-Cell Bolt-On - Manual (Page 76)

Appendix D. System Calibration
D-2
Live Load calibration can be performed by adding or removing a known
quantity of material from the vessel. The quantity of material moved must be
at least 25% of the vessel’s total capacity. The procedures for both Live Load
calibration methods follow.
Note
Refer to the signal processor manual to input Lo Span and Hi Span.
Adding Material
See Figure D-1:
1.
Record the current live load.
2. Input Lo Span:
Lo Span = current live load
3. Add known quantity of material to the vessel. Ensure all material has
stopped moving before proceeding.
4. Input Hi Span:
Hi Span = Lo Span + Added Weight
Example:You are using L-Cells to monitor a vessel. The vessel contains 50,000 lbs of
material and can hold a maximum of 200,000 lbs. You plan to add 60,000 lbs of material
(>25% of 200,000 lbs). Following the Live Load calibration procedure:
1.
Current live load = 50,000 lbs
2. Lo Span = current live load = 50,000 lbs
3. Add 60,000 lbs of material.
4. Hi Span = Lo Span + Added Weight = 50,000 lbs + 60,000 lbs = 110,000 lbs
Removing Material
See Figure D-1:
1.
Record the current live load.
2. Input Hi Span:
Hi Span = current live load
3. Remove known quantity of material from the vessel. Ensure all material
has stopped moving before proceeding.
4. Input Lo Span:
Lo Span = Hi Span – Removed Weight
Example:You are using L-Cells to monitor a vessel. The vessel currently contains
110,000 lbs of material and can hold a maximum of 200,000 lbs. You plan to remove
60,000 lbs of material (>25% of 200,000 lbs). Following the Live Load calibration
procedure:
1.
Current live load = 110,000 lbs
2. Hi Span = current live load = 110,000 lbs
3. Remove 60,000 lbs of material.
4. Lo Span = Hi Span – Removed Weight = 110,000 lbs – 60,000 lbs = 50,000 lbs
Live Load Calibration
Figure D-1. Live Load Calibration by Adding or Removing a Known Quantity of Material
Weight Signal (Counts)
Indicated
Weight
Lo Span
Note: Hi Span and Lo Span establish the
slope and location of the calibration line.
Hi Span
Added or Removed
Known Quantity