How to judge whether a rotary encoder is good or bad?

Rotary encoder are precision components, largely because of interference around the rotary encoder is more serious, such as: whether there is a large motor, electric welding machine is frequent start causing interference, whether the same pipeline transmission and power line, etc. It's also important to choose what kind of output against interference, the general output with reverse signal anti-jamming is better, namely A + to A - ,B+~B- ,Z+~Z- 8, whose character is combined with the power wire, rather than 5 thread ( A total of zero) 。 With reverse signal in the cable transmission is symmetrical, interference is small, can also add judgment in the receiving equipment ( Such as accept equipment signals using A, B & 90 deg; Phase difference, read level 10, 11, 00, 01, four kinds of condition, the meter is an effective pulse, this scheme can effectively improve the system anti-interference performance ( Count accurate) ） 。 There are good and bad is rotary encoder, the encoder, electronic chips, internal circuit, signal output of the difference is very big, or how a 1000 line of incremental encoder will be from 300 yuan to 3000 yuan the difference so big? 1) ruled out ( Move, close, isolation) Interference sources (2) determine whether for mechanical clearance accumulated error (3) determine whether control system and the encoder interface circuit mismatch ( The encoder selection error) (1) (2) (3) methods try after breakdown phenomenon, can preliminary judgment, if did not rule out further analysis. Determine whether simple method for rotary encoder failure itself is functional. Shanghai electronic products co. , LTD. , specializing in the production of rotary encoder, 25 years, already mass production, production technology has been mature, the product failure rate control in a few parts per thousand. Method the specific method is: use a same model rotary encoder to replace, if the same failure phenomenon, is the basic rule out rotary encoder failure problem, because the two rotary encoder and a small probability events occurred with fault may is very small, we can see as 0. If in a same model rotary encoder, immediately ruled out fault phenomenon, is the basic judgement is rotary encoder failure.