How to detect the stand or fall of duplex coder?

Single union encoder is to use more of an encoder, its axis control only a set of encoder. And duplex coder is two encoders with mounted on a shaft, when adjusting shaft, two contact encoder rotate at the same time, so how to detect the stand or fall of duplex coder? With proper range of multimeter resistance, the measured resistance value of duplex encoder on two groups of encoder ( The resistance value between A and C and A resistance value between, C) Whether are the same and is consistent with nominal value. With A wire respectively encoder, C 'A' and encoder, C sub, and then use A multimeter measuring center head B, B ', the resistance value between the ideally, no matter what position encoder shaft to, B, B 'resistance value shall be equal to between two points A and C or A', C 'resistance between two points, The multimeter pointer should always keep in A, C, or A ', C 'resistance on the scale of fixed) 。 If the multimeter pointer deflection, bad is that the synchronization performance of the encoder. Lead to environmental temperature and humidity headphones encoder resistivity inaccurate: general material resistance decreases with the increase of environmental temperature and humidity. Relatively, the surface resistance ( Rate) Humidity is sensitive to the environment, and the body resistance ( Rate) Is sensitive to temperature. Humidity increases, the surface leakage increase, the body electric conduction current will increase. Temperature, the movement of the carrier rate is accelerated, the absorption of dielectric materials and conductance current will increase, according to relevant data, in a normal medium 70 C when the resistance value of only 10% of the 20 C. Therefore, when measuring the resistance of the material, must indicate the sample balance with the environment temperature and humidity. The quality of the encoder will affect your product is good or bad, 26 years, Shanghai electron concentration encoder, our quality target every year in progress, this year our quality goal is: 1. Parts manufacturing batch qualified rate & ge; 99. 3%; 2. Auto product final inspection failure rate & le; 65 ppm; 3. The car product final inspection failure rate & le; 200 ppm; 4. Automotive products customers return defective rate & le; 9 ppm; 5. The automobile products customers return defective rate & le; 270 ppm; 6. Average customer satisfaction & ge; 93 points. Looking for good quality for electronic encoder manufacturers.