GB/T 25930-2010Test method of infrared gas analyzers (English PDF)

4.1 Appearance and completeness inspection of the instrument

Use methods such as visual inspection and hand feeling.

4.2 Safety test

4.2.1 Marking and documents

Inspect visually.

4.2.2 Anti-shock test

4.2.2.1 Pick-up current

4.2.2.1.1 Test exemption conditions

Under normal operating conditions, when the voltage, between the accessible parts and the reference ground, or between any two accessible parts within a distance of 1.8 m (along the surface or through the air) on the same platform, does not exceed 33 V (AC effective value) or DC 70 V, this test is not required.

4.2.2.1.2 Test method

Carry out the test according to the relevant regulations of GB 4793.1-2007.

4.2.2.2 Protective grounding

Carry out the test according to the relevant regulations in Appendix F of GB 4793.1-2007.

4.2.2.3 Dielectric strength

4.2.3 Other safety tests

Perform according to the method corresponding to GB 4793.1-2007.

4.3 Preheating time

Turn on the power of the instrument; continuously inlet the calibration gas of the specified concentration to the instrument; use a recording device whose accuracy is equal to or better than 0.5 to record the output signal of the instrument.

It is the preheating time FROM when the instrument is turned on TO the error of the output signal appears within 30 minutes of the recording line is not more than one-half of the specified range drift. Calculate the relative error delta w according to Formula (1):

Where: Amax, Amin - respectively the maximum and minimum values recorded; R - full range value (same as below).

Note 1: Unless otherwise specified, the inject gas is carried out according to the specified flow rate, same as below.

Note 2: The calibration gas of the specified concentration refers to the calibration gas whose concentration is 70% ~ 95% of the full scale, same as below.

4.4 Air tightness

4.4.1 Use air or nitrogen to test the air tightness of the instrument; the volume of the external pipeline is required to be no more than 0.5 L.

4.4.2 When using positive pressure for the test, the gas outlet end is connected to a 0.5-grade gas pressure gauge (the resolution of the pressure gauge is better than 2.5% of the test pressure), and the gas inlet end is introduced with gas to make the pressure reach 1.5 times the rated working pressure of the instrument; seal the inlet, and start timing after 5 minutes; record the pressure drop within 15 minutes; calculate according to Formula (2).

4.10 Influence of environmental temperature changes on the displayed

value of the instrument The test is carried out in an environmental test box (chamber). The gas source for the experiment is placed outside the box (chamber).

After the instrument is preheated, inlet the calibration gas of the specified concentration; record the displayed value AT0 after it is stable. Adjust the temperature of the test chamber to the lower temperature limit and the upper temperature limit respectively; the temperature change rate is not more than 1 °C/min; keep it for 4 h; record the displayed value AT1 of the instrument at the lower temperature limit and the displayed value AT2 of the instrument at the upper temperature limit; respectively find their differences with AT0, delta AT1 and […]

4.15.3 Interference error of water vapor

Inlet the dry zero calibration gas (the water content to volume ratio is less than 0.1%) into the instrument; record the displayed value A0C; then, pass the zero gas through the water vapor generator to produce about 1.9% ~ 2.0% water vapor concentration; repeat the measurement three times. The calculation method of interference error is the same as that of 4.15.2. During the test, avoid condensation of water vapor before entering the instrument.

Note 1: If a bubbler is used, the temperature of the bubbler shall be controlled at 17°C ~ 18°C.

Note 2: The accuracy of the prepared interference gas can be lower than the accuracy of the usual preparation of calibration gas.

4.16 Electromagnetic compatibility requirements

4.16.1 Electrostatic discharge immunity

Test according to the contact discharge test procedure that is specified in GB/T 17626.2-2006.

4.16.2 Radiated radio-frequency electromagnetic field immunity

Test according to the test procedure that is specified in GB/T 17626.3-2006.

4.16.3 Electrical fast transient/burst immunity

Test according to the test procedure that is specified in GB/T 17626.4-1998.

4.16.4 Surge immunity test

Test according to the test procedure that is specified in GB/T 17626.5-2008.

4.16.5 Immunity to conducted disturbances induced by radio-frequency

fields Test according to the test procedure that is specified in GB/T 17626.6-2008.

Test according to the test procedure that is specified in GB/T 17626.8-2006.

4.16.6 Power frequency magnetic field immunity test

4.16.7

Voltage dips, short interruptions and voltage variations immunity tests Test according to the test procedure that is specified in GB/T 17626.11-2006. […]

4.17 Output interface and output signal