This regulation is applicable to the pattern evaluation, prototype test, first verification, subsequent verification and in-service inspection of liquid level measuring devices.
The liquid level measuring devices include float type, ball float type, displacement type, pressure type, capacitive type, conductivity type and reflex type. Liquid level measuring devices and level meters manufactured in other principles may also be verified with reference to this regulation.
2 Normative references
The following documents are referenced in this regulation:
JJF 1001-1998 General terms in metrology and their definitions
JJF 1015-2002 General norm for pattern evaluation and pattern approval of measuring instruments
JJF 1016-2002 The rules for drafting program of pattern evaluation of measuring instruments
JJG 617-1996 Verification regulation of digital temperature indicators and controllers
JJG 882-1994 Verification regulation of the pressure transmitter
GB/T 17626.2-1998 Electrostatic discharge immunity test
GB/T 17626.3-1998 Radiated radio-frequency electromagnetic field immunity test
GB/T 17626.4-1998 Electrical fast transient/burst immunity test
GB/T 17626.8-1998 Power frequency magnetic field immunity test
GB/T 17626.11-1999 Immunity test of voltage dip, short interruption and voltage change
JB/T 9329-1999 Basic environmental conditions and testing methods for instruments transportation and storage in the transportation
For the purpose of this regulation, the currently effective editions of the above normative references shall be used.
3 Terms and definitions
3.1 set point error
difference between the measured liquid level and the set value of the liquid level, when the output variable is output as specified
3.2 switching value
input (liquid level) value measured when the output changes from one state to the other, in the up stroke (or down stroke) of the stepping control instrument
