2，what are the testing standards of gas detector?-威尼斯2299

1、 appearance and functional inspection

1. check the appearance and other items

appearance detection is the first thing we need to do after purchasing the gas detector. this is to avoid small problems in the transportation or production assembly process of the gas detector. we need to check whether the appearance of the gas detector is defective, cracked or damaged, and check whether the structure of the whole gas detector is complete.

at the same time, check the machine model, label, manufacturer's name and delivery time on the body of the gas detector one by one with the information given in the manual or manufacturer to ensure accuracy. at the same time, check the explosion-proof mark, measurement permission mark and number of the gas detector, which must be complete and clear. some certificates can be provided by the manufacturer.

2. power on inspection

the gas detector needs a power supply. generally, it is powered by a built-in battery. we need to turn on the switch to check whether the gas detector is powered on normally. some gas detectors let it continue to work by replacing the battery. some gas detectors are equipped with chargers. for gas detectors equipped with chargers, we need to test whether the chargers are charged normally, under the condition of normal power on, we need to check whether the display screen of the gas detector is normal.

3. check whether the sound and light alarm of the instrument is normal

for the gas detector with sound and light alarm signal, because it is powered by battery, when under voltage display, it should be able to send out sound or light indication signal which is obviously different from the alarm signal.

2、 indication error

the gas detector we bought is used to detect the gas concentration. the gas detector can't display the gas concentration accurately. it has error, but the error has a range. if it exceeds this range, it means that the gas detector doesn't meet the standard. for different gases, the specified indication error is different. for example, it is normal that the indication error of oxygen is within ± 0.5% vol.

3、 alarm error

we mentioned the error of display value above, so for the alarm value of gas detector, there is a certain allowable error, because the instrument will be affected by various factors, it is impossible to alarm at an accurate concentration every time, so the alarm concentration is allowed to have error, as long as the error is within the standard range. for different gases, the alarm error is also different. for example, the alarm error of oxygen is within ± 0.1% vol.

4、 response time

response time refers to the time required for the indication value of the gas detector to rise from zero to 90% of the stable indication value that the instrument should reach. this time is also required by the standard, which is the same as the indication error and alarm error. for different gases, the response time is different. for example, the response time for oxygen is less than or equal to 20s

5、 insulation and withstand voltage

for gas detector, there are some insulation and withstand voltage standards that must be met, standard requirements: at room temperature: ≥ 100m ω; after damp heat: ≥ 1m ω. the insulation strength should be able to withstand 500v ac voltage for lmin without discharge and breakdown. only when these are met can the gas detector meet the standard.