E8T Miniature Optical Kit Encoder
E8T Product Description
The E8T transmissive optical encoder is designed to provide digital quadrature encoder feedback for high volume, compact space applications. The E8T is designed to be a drop in replacement for the E7P/E8P that offers higher maximum speed and increased output drive. The E8T utilizes an innovative, push-on codewheel which accepts shaft diameters of .118" to .375".
The E8T default encoder base provides mounting holes for two #4-40, length 0.188" or two M2.5, length 5mm screws on a 0.75" bolt circle diameter. A 1.28" diameter bolt circle mount is also available, only with #4-40, length 0.188" screws. The encoder cover is easily snapped onto the base and is marked with the connector pin-out.
The single-ended output version is connected using a 4-conductor, high retention, polarized, 1.25mm pitch connector. The differential output version uses a similiar 6-pin connector. Mating cables and connectors (see the Cables / Connectors web page) are not included, and are available separately.
View here or download the specifications
|Operating Temperature||-20 to 100||C|
|Electrostatic Discharge, IEC 61000-4-2
Single-ended (-S option)
Differential (-D option)
|Shock, 6 millisecond, half-sine||75||G|
|Vibration (20Hz to 2kHz, sinusoidal)||20||G|
|Max. Shaft Axial Play||± .010||in.|
|Max. Shaft Runout (TIR)||.002||in.|
Maximum RPM (1)
|minimum value of
|Codewheel Moment of Inertia||1.789 x 10^-6||oz-in-s²|
|Mounting Screw Size
Default (D-option), 1.28" base (G-option)
#4-40, length 0.188"
M2.5, length 5mm
|Screw Bolt Circle Diameter
Default (D-option), Metric (M-option)
1.28" base (G-option)
|Minimum Shaft Length (2)||.295||in.|
|Maximum Shaft Length (2)||.400 (D option) /
no limit (H option)
|Mounting Screw Torque||2-3||in-lbs|
|Technical Bulletin TB1001 - Shaft and Bore Tolerances||Download|
(1) 60000 RPM is the maximum rpm due to mechanical considerations. The maximum RPM due to the module's 100kHz maximum output frequency is (6000000/CPR).
(2) Including axial play.
|Supply Current||25||30||mA||no load|
|Low-level Output||0.4||V||IOL = 8 mA|
|High-level Output||2.4||V||IOH = -8 mA|
|Output Rise Time||100||ns||no load|
|Output Fall Time||50||ns||no load
|Supply Current||27||32||mA||no load
|Differential Output Voltage High||4.75||5.0||V||Min. @ 25mA load, Typ. @ no load|
|Differential Output Voltage Low||0.25||0.60||V||Typ. @ no load, Max. @ 4.5mA load|
|Differential Output Voltage||3.0||3.8||V||RL = 100 ohm|
|Differential Output Rise/Fall Time||20||ns|
|Symmetry, S||105||180||255||electrical degrees|
|Quadrature Delay, Q||30||90||150||electrical degrees|
(1) A leads B for clockwise shaft rotation, B leads A for counter clockwise shaft rotation viewed from the cover side of the encoder.
(2) Typical values represent the encoder performance at typical mounting alignment, whereas the maximum values represent the encoder performance across the range of recommended mounting tolerance.
H-option (Hole In Cover)
The H-option adds a 0.425" diameter hole in the cover for the shaft to pass through.
M-option (Metric Mounting Screws with Default base)
Provides metric M2.5, length 5mm screws. When M-option is NOT specified the default is #4-40, length 0.188" screws. The mounting bolt circle diameter is 0.75"
G-option (1.28" diameter bolt circle mount)
Provides 1.28" diameter bolt circle mount in addition to 0.75" diameter bolt circle mount. Screws are #4-40, length 0.188"
1. Centering Tool*
Part #: CTOOL - (Shaft Diameter)
Description: This reusable tool is used to accurately center the E8T base on the shaft.
2. Spacer Tool*
Part #: SPACER-E8T
Description: This reusable tool is used to properly gap the codewheel from the encoder sensor.
*Both the CTOOL and SPACER-E8T tools are included with all packaging options.
Product Change Notifications
|Updated PCB on the US Digital E8T - PCN 6514||5/16/2018||This notice is to inform our customers of a PCB design change that is being implemented for the entire E8T product line. As part of our continuous improvement objective, the new PCB will improve overall product performance and enhance robustness of this product line. The new PCB has two mounting holes that mate with the base plate instead of one hole and one slot. This change has no impact on form, fit or function for the E8T.||Download|
|E4T, S4T and E8T Laser Markings - PCN 6227||8/8/2017||This notification is to inform our customers of a change to product markings for the E4T, E8T, and S4T series of encoders. The new marking will be utilized across all three product lines. We are making this change to improve readability for our customers and to provide consistency across the product lines.
3D Model Downloads
Please configure your product first to download a 3D model.
(Note: The formats below will become links if there are 3D models available.)
- SolidWorks format
- IGES format
- Parasolid format
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