Adjustment and use:

1Adjustment:

（1）After taking out the micro manometer from the inner packing box, place it on a flat workbench, take out the plastic sleeve, and then adjust the adjusting screw to make the instrument horizontal (observe the bubble of the level bubble in the middle of the black circle)

（2）Adjust both the fine-tuning dial and the indicator block to“0”After clicking, connect the dynamic pressure nozzle with a rubber hose, pour in distilled water, observe from the mirror that the water level head is approximately in contact with the liquid level, stop adding water, and then slowly adjust the adjustment disk to rise and fall several times to eliminate the air inside the connecting tube. After the above process, adjust the dynamic pressure tube adjustment nut to achieve the requirement of the liquid level being tangent to the needle tip3~5It can remain stable after minutes.

2. Use:

1. When used for standard transmission, it should be carried out in accordance with the inspection regulations stipulated by the national metrology institution.

The instrument also needs to purchase a pressure regulator.

（2）If used as a working instrument:

aWhen measuring pressure, the pressure nozzle should be connected to the dynamic pressure nozzle of the micro pressure gauge with a rubber tube (ensuring good airtightness), and the fine adjustment dial should be turned to connect the level head shadow and the reflection shadow tip on the observation mirror surface. At this time, the value should be read on the scale plate and the value should be read on the fine adjustment dial. The sum of the two numbers is the instrument readingmmThe measured pressure value is determined by the following equation:

P＝h`g`ρ（1﹣ρ′/ ρ）·10ˉ³

P- Tested pressure (Pa)

h- Instrument reading (mm)

ρ- Density of water at verification temperature（Kg/m³）

ρ′?Air density at ambient temperature（Kg/m³）

g- Use location gravity acceleration（m/s²）

bWhen measuring negative pressure, connect the negative pressure nozzle to the static pressure nozzle of the micro pressure gauge with a rubber tube, read the reading and calculate it according to the same method as above, which is the measured negative pressure.

CWhen measuring the pressure difference, the positive and negative pressure nozzles to be measured should be connected to the corresponding nozzles of the micro pressure gauge with rubber guides

Pipe connection, according toaThe same method is used to read the indication difference and calculate it to obtain the measured pressure difference.

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5、 Maintenance and precautions:

1、 Maintenance:

（1）Micropressure gauges should be kept clean regularly and carefully cared for. After use, they should be cleaned and the plastic cover should be properly placed to prevent dust from entering the liquid level and blurring the tangent point between the liquid level and the needle tip, resulting in reading errors.

（2）When removing dust from the mirror surface, a fine soft cloth that does not damage the mirror surface should be used for wiping.

2、 Attention:

（1）When conducting a sealing check on this instrument, the pressure must not exceed the upper limit of the measurement, otherwise the instrument may get stuck.

（2）When the micro adjustment disc is approaching the top or bottom of the rotation, it should not be rotated forcefully anymore, otherwise it may cause the instrument to jam and affect its accuracy.

（3）There should be no vibration during use, even slight vibrations can cause fluctuations in the liquid level and affect the reading.

（4）Under normal use, it is not allowed to turn the fastening screws of each connecting part. Prevent air leakage.

（5）When using a micro pressure gauge, it should2Replace the distilled water in about a month. When not in use for a long time, release the distilled water, wipe it clean, and cover it with a plastic sleeve. Store in a protective wooden box, but the storage room requires room temperature at-10℃~＋40℃The relative humidity should not exceed80There should be no corrosive volatile substances present in indoor air.