How to judge the stand or fall of the encoder? Daqo encoder test method

Encoder in use process, prone to failure due to rotation frequency. This fault is small, large noise and sound power switch failure, etc. So how do we judge of the encoder? Electronics, here to teach you a simple encoder test method. Ready to common tools, multimeter. Example: with A, B fixed end of said encoder, P said the slide end of the encoder. . ( 1) Measuring encoder. A, B is the total resistance is in line with the nominal value take pens and respectively in A, B, whether the multimeter reading is consistent with the nominal value. ( 2) Detect the activities of the encoder arm contact with the resistors are in good condition with A multimeter ohm block test, P or P, B at both ends, slowly turn the encoder, resistance should be continuously becomes large or small, if there is resistance, contact shows activity have poor contact failure. ( 3) The stand or fall of measuring switch encoder with encoder switch, check the available digital multimeter measuring diode block by measuring 'switch' between the two welding pieces of on-off situation to judge whether it is normal. If the 'switch' when closed, digital multimeter sounding, shows the internal switch touch point contact bad; If the 'switch' opens, digital multimeter without sounding, shows the internal switch is out of control. ( 4) Check the shell and the insulation will be digital multimeter pin a pens and encoder housing, another pens and contact them one by one each pin, resistance should be infinite; Otherwise, defective insulation between shell and pins.