SU Puresonic flowmeter
Performance

Excellent accuracy and repeatability

Industrial:
Part No.	Line size Nominal flow rate	10% of max flow	50% of max flow	100% of max flow
Part No.	Line size Nominal flow rate	10% of max flow	50% of max flow	100% of max flow	Repeatability
		Accuracy (2% MW + 0.5% MEW)*			(0.2% MEW)
SU6x21	½” NPT / G1/2 0.13…17.17 gpm 0.5…65 lpm	+/- 0.12 gpm +/- 0.46 lpm	+/- 0.26 gpm +/- 0.98 lpm	+/- 0.43 gpm +/- 1.63 lpm	+/- 0.03 gpm +/- 0.13 lpm
SU7x21	¾” NPT / G3/4 0.13…19.81 gpm 0.5…75 lpm	+/- 0.14 gpm +/- 0.53 lpm	+/- 0.30 gpm +/- 1.13 lpm	+/- 0.50 gpm +/- 1.86 lpm	+/- 0.04 gpm +/- 0.15 lpm
		Accuracy (1% MW + 0.5% MEW)*			(0.2% MEW)
SU8x21	1" NPT / G1 0.25...63.40 gpm 1...240 lpm	+/- 0.38 gpm +/- 1.44 lpm	+/-0.63 gpm +/- 2.40 lpm	+/- 0.95 gpm +/- 3.60 lpm	+/- 0.13 gpm +/- 0.48 lpm
SU9x21	G 1-1/4" 0.26...72.64 gpm 1...275 lpm	+/- 0.44 gpm +/- 1.65 lpm	+/- 0.73 gpm +/- 2.75 lpm	+/- 1.09 gpm +/- 4.13 lpm	+/- 0.15 gpm +/- 0.55 lpm
SU2x21	2" NPT / G2 1.32...264.18 gpm 5...1,000 lpm	+/- 1.59 gpm +/- 6.0 lpm	+/- 2.64 gpm +/- 10.0 lpm	+/- 3.96 gpm +/- 15.0 lpm	+/- 0.53 gpm +/- 2.0 lpm

Sanitary:
Part No.	Line size Nominal flow rate	10% of max flow	50% of max flow	100% of max flow
Part No.	Line size Nominal flow rate	10% of max flow	50% of max flow	100% of max flow	Repeatability
		Accuracy (1% MW + 0.5% MEW)*			(0.2% MEW)
SUH20x	1" Tri-clamp 0.25...63.40 gpm 1...240 lpm	+/- 0.38 gpm +/- 1.44 lpm	+/-0.63 gpm +/- 2.40 lpm	+/- 0.95 gpm +/- 3.60 lpm	+/- 0.13 gpm +/- 0.48 lpm
SUH40x	2" Tri-clamp 1.32...264.18 gpm 5...1,000 lpm	+/- 1.59 gpm +/- 6.0 lpm	+/- 2.64 gpm +/- 10.0 lpm	+/- 3.96 gpm +/- 15.0 lpm	+/- 0.53 gpm +/- 2.0 lpm

Note: Performance specifications of the ultrasonic flow meter are true across the full temperature rating of -4...212°F (-20...100°C).
* MW = measured flow rate; MEW = full range flow rate

Accuracy and reliability calculation examples

Most of ifm’s flow meters use a two-part accuracy calculation, based on the measured flow rate (MW) and full range of the meter (MEW). For example, accuracy of the SU8621 (MEW = 63.40 gpm) is specified as:

± (1 % MW + 0.5% MEW)
For MW = 50 gpm, accuracy = ± (0.01*50 + 0.005*63.40) = +/- 0.817 gpm

The repeatability calculation is consistent over the entire flow measuring range of the unit. For example, repeatability of the SU8621 (MEW = 63.40) is specified as:

± (0.2% MEW)
repeatability = +/- (0.002*63.40) = +/- 0.1268 gpm