Emerson Process Management 3400, 3410, 3420, 3422 CalMethod, CalMethod, Mark III Calibration, Calibration Parameter Conversions, Reference, Installation, and Operations Manual

	Reference, Installation, and Operations Manual	Upgrading a Mark II to a Mark III
3-9000-743 Rev S		June 2013

Mark III Calibration

The Mark III calibration is comprised of two basic steps:

1.application of the “dry-calibration” “A” polynomial coefficients (see Equation C-4)

2.application of one of the following “wet-calibration” methods (or none at all):

•“C” polynomial coefficients (see Equation C-5)

•12-point linearization

In this methodology, the “dry-calibration” values are set by Daniel at the factory and are not expected to be modified; the “wet-calibration” values are expected to be set as the result of a user flow calibration (if desired).

Equation C-4 Mark III Application of the “A” Polynomial Coefficient

vDryCal = A0 + A1vAvgWtd + A2v2AvgWtd + A3v3AvgWtd

Equation C-5 Mark III Application of the “C” Polynomial Coefficient

vWetCal = C0 + C1vDryCal + C2v2DryCal + C3v3DryCal

Calibration Parameter Conversions

The calibration parameter conversion involves the Mark II British Gas Factor (BG) and either the Mark II “A” polynomial coefficients or the (Velocity Offset, Meter Factor) depending upon which values were used. If the Mark II “A” polynomial coefficients were not equal to [0,1,0,0] nor [0,0,0,0], then the Mark II used the “A” polynomial coefficients; otherwise it used the Velocity Offset and Meter Factor. The conversions are described in detail below.

If the Mark II meter did not utilized piece-wise linearization (PWL), then the Mark III meter’s calibration method (CalMethod) is set to ‘None’. Otherwise, the Mark II PWL values are converted for the Mark III as follows:

•The Mark III meter’s calibration method (CalMethod) is set to select the piece-wise linear wet-calibration method.

•The Mark II meter’s ten PWL points (flow rate and meter factor) are copied directly to the Mark III meter’s first ten PWL points. The Mark III meter’s 11th and 12th PWL points are set for flow rate of 0 and meter factor of 1.

Converting Mark II “BG” and “A” Polynomial Coefficients

The Mark II British Gas Factor (BG) and “A” polynomial coefficients are converted to equivalent Mark III dry-calibration “A” polynomial coefficients as shown in Equation C-6below. Note that both the forward and reverse “A” polynomial coefficients are converted using the same equations.

Metrology - calibration equation parameters 305