1、 Standard Operating Procedure for Salt Spray Test Chamber

1. Preparation before the experiment

-Check the salt water ratio: Prepare a 5% ± 1% sodium chloride solution according to the standard (refer to ISO 9227 requirements), and it is recommended to use deionized water to avoid interference from impurities.

-Fill the saturated tank: Ensure that the water level in the saturated air tank is higher than the heating tube, and the temperature should be stable at 47 ℃± 2 ℃ (within the range specified in ASTM B117).

-Sample placement: the sample is inclined at 15 ° -30 ° to avoid mutual contact or blocking the spray path.

2. Equipment parameter settings

-Continuous gear symbol setting: select the 'continuous spray' mode through the control panel (the icon is usually an ∞ symbol), and set the cycle together with the programming timer. For example:

Example setting: spray for 60 minutes → pause for 15 minutes → cycle for 10 times

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-Function of accumulator: Accumulate the total operating time of the equipment (accuracy ± 0.1%), used for maintenance cycle determination (such as replacing the saturation tank filter element after 500 hours).

-Function of programming timer: Control the segmented process of the experiment, support multi-stage cyclic programming (up to 99 sets of parameters), and ensure compliance with the alternating salt spray test standards.

3. Operation and monitoring

-After startup, record the box temperature (35 ℃± 2 ℃), spray volume (1.0-2.0ml/80cm ²/h) and other data every hour.

-When the 'operation H' alarm occurs, it indicates that the temperature or pressure exceeds the limit, and the status of the heater/compressor needs to be checked immediately (commonly triggered by protection when the box temperature exceeds 50 ℃).

2、 Deep analysis of key functions

1. Interactive interface operation guide

-Switching between continuous spray and intermittent spray: select by the 'Mode' key, and adjust the interval time with ▲/▼ keys (accurate to 1 second).

-Fault code handling:

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E01: Sensor malfunction

E02: Insufficient saltwater

E03: The box door is not closed

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2. Maintenance points

-Clean the nozzle (aperture 0.5-0.7mm) daily to prevent salt crystallization from clogging.

-Calibrate the pH value monthly (between 6.5-7.2), and use a pH meter to measure the deviation, which should be ≤ 0.1.