The opening sentence of the HZBD-1177 instruction manual, 'With just a gentle press, the experiment will be automatically completed,' is accurate, but the prerequisite is that every step of the preparation work is in place. Organize the complete operation process and follow it without any problems.

Step 1: Check the alcohol level and turn on the device

Before starting up, check the alcohol level in the cold bath, which must be higher than the refrigeration coil and sample level. If insufficient, add anhydrous ethanol first, and then connect the power supply (220V/10A or above, must have a good grounding wire).

After booting up and entering the main interface, do not immediately click "start" - this is a detail that is easily overlooked. The instruction manual clearly requires that when entering the system settings interface, first turn on the refrigeration device to lower the temperature of the bath by 3-5 ℃ (because the temperature of the test tube lags behind the bath), and then return to the main interface to prepare for the experiment. Directly starting without pre cooling will result in no cooling effect in the first few minutes and prolonged measurement time.

Step 2: Parameter Setting

Click on 'Parameter Settings' to confirm or modify:

Date and time: Ensure that the historical data archive time is correct

Sample number: convenient for historical data query and report generation

Expected freezing point: Fill in the approximate freezing point of the tested coolant - this parameter directly affects the timing of measurement and the temperature control range of the bath

Expected freezing point setting logic: The instrument detects the freezing point from 15 ℃ above the expected freezing point and records the temperature every 15 seconds. If the expected freezing point has not been detected by the time it is reached, the instrument will automatically extend the detection to 30 ℃ below the expected freezing point to provide sufficient detection range.

Step 3: Sample installation

Take 75-100mL of the sample from the measuring cylinder, put it into a clean and dry freezing point test tube, and cover it with a rubber stopper. Install the sensor in the center position of the mixer ring, ensuring that the sensor is in full contact with the sample but not with the pipe wall. After adjusting the position of the mixer, place the test tube in a cold bath.

Step 4: Start testing

After everything is ready, click the "Start" button on the main interface. The entire experiment is automated: the instrument automatically cools down, monitors the temperature curve, identifies the freezing point inflection point, beeps after the test is completed, the mixing motor automatically stops, the freezing point results are automatically printed, and the results are saved to the historical database.

Step 5: Post completion processing

After the experiment is completed, enter the system settings interface to turn off the compressor. To quickly return the bath to room temperature, the heating device can be turned on in the system settings. When the cold bath temperature rises to about 15 ℃, the heating system will automatically turn off.