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MDE-4334C Atlas Start-up and Service Manual · April 2008
Hydraulic/Mechanical Components
Meter Calibration
• National Institute of Standard and Technology (NIST) Handbook 44 permits these
operating tolerances:
- Plus or minus three-cubic inches ‘acceptance tolerance’ (typically at the time of
installation)
- Plus or minus six-cubic inches ‘maintenance tolerance’ (typically 30 days after
installation)
Note: Weights and Measures require meters to be calibrated as close to zero as possible.
• Local Weights and Measures authorities requirements may differ from Handbook 44.
• Calibrate the meter within its rated flow range. Meter calibration must remain at the same
setting and within the acceptable tolerance for both high and low flow rates.
In new systems,
all meters
must be checked for accuracy after purging air from the
system. Air in the system affects calibration accuracy.
IMPORTANT INFORMATION
CFT Meter Calibration Adjustment for Standard, Hi-Flow, and Super-Hi
Models (All Models Excluding 9850K and 9850KX)
Note: The procedure for calibrating the Liquid Control (LC) Meter is different.
If calibration is required, remove the restraint (seal wire from locking pin) on the calibration
wheel located on each meter. Each adjacent pin hole represents 2/3 cubic inches (0.011 liter)
variance for a 5-gallon (18.9 liter) measure. Moving the calibration wheel counterclockwise
by one pin hole adds 2/3 cubic inches of fuel (0.011 liter) in the prover can, while turning the
calibration wheel clockwise by one pin hole creates a negative 2/3 cubic inch of fuel in the
prover can.
Note: It is the owner’s responsibility to notify the local Weights and Measure officials if their
inspection is necessary before the unit is put into service.
Local or state regulations frequently require testing and calibrating units at both fast
and slow-flow nozzle settings. If required in your area, adjust settings such that both
fast and slow-flow readings are in compliance. Consult your local regulatory agency for
guidance.
IMPORTANT INFORMATION
Note: For units with two meters supplying one (Super-Hi) hose, a variation of this process is
required. When adjusting meters, split the adjustment between the two meters instead of
adjusting only one meter. Life of the meters can be negatively affected if this is not done.
For electronic units, pricing (temporary or permanent) must be entered into the unit as outlined
in the purging section to allow dispensing and calibration.