KROHNE WATERFLUX 3070 EN - Manual (Page 67)

TECHNICAL DATA
8
67
WATERFLUX 3070
www.krohne.com 06/2013 - 4001410205 - HB WATERFLUX 3070 R05 en
8.3 Legal metrology
8.3.1 OIML R49
The WATERFLUX 3070 has a certificate of conformity with the international recommendation
OIML R49. The certificate has been issued by NMi.
The OIML R49 recommendation (2006) concerns water meters intended for the metering of cold
potable and hot water. The measuring range of the water meter is determined by Q3 (nominal
flow rate) and R (ratio).
The WATERFLUX 3070 meets the requirements for water meters
of accuracy class 1 and 2.
• For accuracy class 1, the maximum permissible error for water meters is ±1% for the upper
flow rate zone and ±3% for the lower flow rate zones.
• For accuracy class 2, the maximum permissible error for water meters is ±2% for the upper
flow rate zone and ±5% for the lower flow rate zones.
According to OIML R49, accuracy class 1 designation shall be applied only to water meters with
Q3 ≥ 100 m
3 /h.
Q1 = Q3 / R
Q2 = Q1 * 1.6
Q3 = Q1 * R
Q4 = Q3 * 1.25
Figure 8-1: ISO flow rates added to figure as comparison towards OIML
X: Flow rate; Y [%]: Maximum measuring error
1 Upper flow rate zone: ± 3% (class 1), ± 5% (class 2)
2 Lower flow rate zone: ± 1% (class 1), ±2% (class 2)