Specifications

molbox™ RFM™ OPERATION AND MAINTENANCE MANUAL

1.2.4.1.1 molbloc-L FLOW MEASUREMENT

SPECIFICATIONS, MICRORANGE OPTION

The microrange option (see Section 1.2.2.2) improves molbloc-L flow

measurement specifications below 10 % FS of the molbloc range. With the

microrange option, the affected measurement specifications below 10 % FS

become:

Resolution

0.01 % of 10 % FS (0.001 % FS)

Linearity

± 0.23 % of reading from 1 to 10 % FS

Repeatability

± 0.1 % of reading from 1 to 10 % FS

Precision

± 0.25 % of reading from 1 to 10 % FS

Stability

(1 year)

± 0.15 % of reading from 1 to 10 % FS

Measurement Uncertainty

(1 year, N2 and any molbox RFM

supported gas for which the molbloc in

use is calibrated)

± 0.5 % of reading from 1 to 10 % FS

1 Precision: Combined linearity, hysteresis, repeatability.

2 Stability: Maximum change in zero and span over specified time period for typical molbox RFM and

molbloc used under typical conditions. As stability can only be predicted, stability for a specific

molbox RFM should be established from experience.

3 Measurement Uncertainty (Accuracy): Maximum deviation of the molbox RFM flow indication from

the true value of the flow through the molbloc including precision, stability and DHI calibration

standard measurement uncertainty.

1.2.4.1.2 molbloc-L PRESSURE DEPENDENT CALIBRATION

TYPES

See your molbloc’s Calibration Report to determine the calibration type of

the molbloc you are using.

Different pressure dependent calibration options for molbloc-L elements determine

the range of operating pressures over which a molbloc can be used within its

mass flow measurement specifications. The calibration option also affects the

molbloc flow range and the differential pressure associated with the flow range.

Measurement uncertainty (accuracy) specifications for molbloc-L are valid only

for gases with which the molbloc has been calibrated. All molbloc-L elements

are calibrated for N2. Calibrations with other gases are optional. DHI calibration

capability is not maintained at all times for all gases on all molbloc designations.

Check for availability before ordering calibrations.