This instrument has a compact structure, stable performance, small size, light weight, and is easy to carry. It is currently an ideal instrument among small portable atmospheric sampling instruments in China. By switching different sampling loads, toxic gases can be collected, as well as dust and activated carbon sampling tubes, making it suitable for multifunctional atmospheric environment monitoring and achieving multiple uses for one machine.

The instrument casing is made of high-strength AS and ABS colored engineering plastics, and has undergone special treatment for moisture, dust, and static electricity prevention. There are three colors available for purchase: black, dark gray, and blue, with fading.

1、 Introduction to Instrument Structure:

The main components of the sampler include a diaphragm pump, regulating valve, buffer, flow meter, electronic timing circuit, undervoltage indicator circuit, and power supply.

1. The structure and assembly of the diaphragm pump adopt advanced technology, making the small pump have the advantages of compact structure, high efficiency, high pumping pressure, strong load capacity, stable flow rate, low power consumption, and low noise. Under a load capacity of 100mmHg, it can still achieve around 1L/min. The pump valve plate is made of special rubber, which has acid and alkali resistance, aging resistance, and long service life. After long-term testing, its performance still remains good. The pump power motor adopts electronic speed regulation, which can ensure stable operation of the motor even under significant voltage fluctuations and changes in dry battery voltage drops. When the load changes within a certain range during the sampling process, the electronic circuit can adjust the power to stabilize the flow rate of the diaphragm pump.

2. The time control mechanism of this machine adopts a fixed 8-speed timing structure, which does not need to be adjusted before each sampling, nor will it be unverifiable due to adjustment errors.

The 8-speed selector switch can be selected according to the requirements of the conditions, as shown in the table for time shutdown. Simply turn the small switch of a certain gear to "ON" to obtain the required time shutdown. If two or more gears are simultaneously turned to "ON", timing errors will occur. All 8 switches are in the off position, and the instrument is not working. Considering that there are different requirements for the selection time of operators, manual mode is set in "1" mode, and users can shut down according to their own needs.

3. Work instructions and undervoltage indicators are used to ensure the efficiency of operators and make the instrument more practical. The TWA-300A small sampler is equipped with a working indicator and an undervoltage indicator, which can clearly tell the operator when to replace the dry battery. The red light is on during normal operation, and when the voltage drops to 6V, the red light automatically goes out, indicating battery undervoltage. This is also an essential protective function for nickel barrier batteries.

4. The power supply instrument is equipped with a dual-purpose power supply of "charging stabilizing". During normal sampling, the power switch is in the "stabilizing" position and outputs 8V DC voltage; When used for charging, the power switch should be in the "charging" position, and the sampler switch should be turned off to automatically charge. When the battery voltage of the sampler reaches the rated value, the charger indicator light will automatically turn off, indicating the end of charging. It is convenient to use dry batteries for outdoor sampling without AC power supply. A 6-cell 5 # dry battery typically lasts for about 4.5 hours, while a nickel separated battery can last for about 8 hours. If the sampler indicator light goes out, it indicates undervoltage and the dry battery needs to be replaced. If the nickel battery is under voltage, it needs to be charged.

IIIndividual air samplerTechnical parameters:

1. Maximum extraction pressure: ≥ 13000pa

2. Rated load flow rate: ≥ 1.5L/min (at 40mmHg)

3. Flow usage range: 20~500ml/min

4. Traffic accuracy: Level 2.5

5. Stability: ≤ ±5％

6. Electronic timing error: ≤ ±1％

7. Working temperature: 5-40 ℃

8. Instrument usage status: continuous and intermittent use

9. Power supply: AC/DC dual-use

10. Volume: 137 × 88 × 45 (mm3)

11. Weight:< 0.5Kg (including battery)

IIIIndividual air samplerUsage and maintenance:

1. Pull out the battery cover of the sampler, insert 6 No. 5 dry batteries or rechargeable batteries, cover the cover, then gently pull the timing adjustment cover to the left, select the desired timing time (such as "2" position, 10 minutes at this time), and push the sampler power switch upwards. The red indicator light will turn on, and the instrument will start working. The timing accuracy can be calibrated with a stopwatch.

Attention: If not used for a long time, the battery should be removed to prevent liquid from leaking out and damaging the internal components of the machine when the battery deteriorates.

During the sampling process, connect a filter to filter out dust, aerosols, acid and alkali gases and other impurities in the air; On the other hand, when a backflow of solution occurs, once the solution passes through the filtering fibers of the filter, the fibers will immediately expand, blocking the intake passage and providing protection to the components, especially the pump. In case of solution backdraft, clean the filter and replace it with filter fiber and foam block. If it is used for a long time, the filter fiber and foam block should also be replaced to prevent dirt from passing through the filter mass and entering the pump, which will increase the air resistance and reduce the flow.

3. If accidentally inhaling acidic or alkaline solutions during operation, it is necessary to immediately inject distilled water for cleaning several times, and then inject anhydrous ethanol for cleaning. Generally, the work can be restored. If the damage is severe, it should be sent back to the factory for repair or sent to a designated station for repair.

4、 Other:

1. Instrument accessories

Instrument packaging box (every two instruments) 1 piece

1 filter

1 smart charger

1 connecting pipe

1 backpack

1 copy of instruction manual

1 certificate of conformity

1 warranty card

2. There are also various glass absorption bottles, small plastic sampling heads, activated carbon sampling tubes, etc. available for purchase.

3. The product implements lifelong service. Within one month after purchasing the product, if it is found that the quality does not meet the technical specifications, you can request a replacement or return (with no damage or disassembly of the instrument inside and outside).