US Digital | FIRST US Digital designs and manufactures incremental and absolute magnetic and optical encoders, inclinometers and interfaces for the OEM manufacturer. Made in the USA. Copyright 2008 US Digital. Thu, 17 May 2012 00:10:11 PDT What are the electrical signals I need to hook up? Thu, 17 May 2012 00:10:11 PDT +5 VDC power Quadrature A channel Ground Quadrature B channel How do I connect to the E4Ps? Thu, 17 May 2012 00:10:11 PDT Use the provided cable(s). If you need other cabling options, browse our 4-pin cables . What resolution are these encoders? Thu, 17 May 2012 00:10:11 PDT The encoders provided are 360 CPR. With 4X quadrature decoding, you get 1440 positions per revolution. Which gives you a unique position every 0.25 degrees. The maximum RPM for these encoders is 10,000 RPM. Here is how maximum RPM is calculated: For the E4P, the maximum output frequency is 60 kHz (60,000 cycles per second). A 360 CPR encoder produces 360 pulses on each channel per revolution. To solve for how fast the encoder's shaft must turn per second to reach the maximum output frequency, divide the maximum frequency by the pulses per revolution. 60,000 / 360 = 166 revolutions per second. To convert to RPM multiply by 60 (10,000 RPM). What is quadrature? Thu, 17 May 2012 00:10:11 PDT Most incremental encoders provide quadrature output signals. A single track optical disk encoder can provide speed information only. Adding a second track to the optical disk and offsetting it by 1/4 cycle from the first track is quadrature and provides two advantages: Rotation direction can be determined by examining the relative phase of the two channels (i.e. whether A-leads-B or B-leads-A) The encoder resolution is effectively increased since there are now 4 transitions for each line pair, instead of 2.   What is the difference between absolute and incremental encoders? Thu, 17 May 2012 00:10:11 PDT Absolute encoders can determine their position at power up. Incremental encoders only show relative movement after power up and would require a homing cycle in some applications. How do I assemble the E4P? Thu, 17 May 2012 00:10:11 PDT See the E4P assembly instructions . What can the E4P measure? Thu, 17 May 2012 00:10:11 PDT E4Ps are incremental encoders outputting 2-channel quadrature. They are capable of measuring shaft position, speed and direction. What encoders are included in my kit? Thu, 17 May 2012 00:10:11 PDT Your kit includes two E4P-360-250-D-H-D-B . These are miniature optical encoders with two-channel quadrature outputs. They are 360 codes per revolution and fit on a 0.25" shaft. See the E4P web page .