1、 Reasons and Handling of Deviation in Measurement Results

Prism contamination or wear

Reason: Abnormal refraction of light caused by sample residue, oil film, or scratches.

Solution: Dip lens paper in anhydrous ethanol or isopropanol to wipe the prism surface in one direction; Stubborn residues can be quickly wiped with trace amounts of acetone and rinsed. If the prism is severely worn, it needs to be returned to the factory for replacement of the sapphire prism.

Unstable temperature

Reason: The temperature control module has not reached the target temperature or the ambient temperature fluctuates greatly.

Processing: Confirm that the instrument displays "temperature stable" (temperature control accuracy within ± 0.02 ℃) before calibration/measurement; Move the instrument to a constant temperature environment, away from air conditioning and heating; Check whether the cooling fan has accumulated dust or is faulty, and replace it if necessary.

Calibration solution failure

Reason: Expired calibration solution or concentration change.

Solution: Use a standard solution within its validity period (such as deionized water with a refractive index of 1.33300 at 20 ℃) to recalibrate.

Light source aging

Reason: Sodium lamp/LED brightness attenuation.

Solution: Check if the light source indicator light is normal. If it is dim/not on, contact the manufacturer to replace the light source module.

2、 Reasons and Handling of Alarm Malfunctions

Alarm for "no signal" or "abnormal light path"

Reason: The prism sample cell is not filled with samples, the optical path is blocked, or the photoelectric sensor (CCD) is malfunctioning.

Processing: Empty the sample pool and refill with sufficient bubble free samples; Check that there are no foreign objects in the optical path channel and that the injection tube is not offset; If the CCD sensor malfunctions, please contact the manufacturer for repair.

Temperature Alarm

Reason: Poor heat dissipation of Peltier module or malfunction of temperature sensor.

Solution: Clean the cooling fan. If the fan does not turn, replace it; If the temperature display is abnormal (with a deviation of>0.5 ℃ compared to the thermometer), it is necessary to contact the manufacturer to calibrate the temperature sensor.

Sample injection system alarm (such as leakage or inability to inject)

Reason: Loose interface of the injection tube, aging of the sealing ring of the sample cell, or blockage of the injection tube.

Solution: Tighten the interface and replace the sealing ring; Use a syringe to extract cleaning solvent and rinse the injection tube in reverse. If there is persistent blockage, inject a small amount of warm water (≤ 40 ℃) and soak for 5 minutes before rinsing.