Click to Zoom
QR145 Download Spec Sheet


QR145 Optical Rotary Encoder

  • Overview
  • Specifications
  • Info & Pricing

About QR145 Optical Rotary Encoder

Quantum Devices Model QR145 optical incremental encoder provides an improved feedback solution in applications typically using modular encoders. With an overall height of only 0.87” and the stability of a bearing encoder design, the model QR145 optical incremental encoder can provide significant performance upgrades in applications limited by traditional modular encoder solutions. Outputs consist of a quadrature with reference pulse and three-phase commutation, which can be configured with either the industrial standard 5 volt RS-422 Line Driver or the 5 to 26 volt OL7272 line driver. A flexible spring mount allows for much greater tail shaft run out than can be tolerated by modular encoder designs, plus it provides 30 degrees of rotation for commutation timing. A housing constructed of conductive carbon fiber composite provides the EMI shielding of an all metal housing and the performance of a lightweight robust assembly. An optional IP66 housing is available at a fraction of the cost of competitors’ comparable sealed encoders. Use QR145 with our QC201 Commutation Indicator for easier motor encoder alignment.

Contact Quantum Devices to customize QR145.

QR145 Optical Incremental Encoder Design Features:

  • 500 kHz fundamental frequency response
  • Low profile, 0.87″ assembled height
  • Bearing design simplifies encoder attachment
  • Resolution up to 5000 lines per revolution direct read
  • 4, 6 or 8 pole commutation
  • Conductive carbon fiber housing
  • 1.575″, 1.812″ bolt circle or size 15 resolver mounting
  • Optional IP66 housing
  • Through shaft sizes up to 0.375″ (10 mm) diameter
  • High noise immunity
  • Cost competitive with modular encoders


Note: prior to transitioning to RoHS-compliant, the product name was QD145 rather than QR145. Therefore, when cross-referencing a QD145 configuration, simply substitute the configuration prefix with QR145.


QR145 Optical Encoder Electrical Specifications

Input Voltage 5 VDC ±5% or 5-26 VDC
Input Current Requirements 125 mA typical @ 5 VDC plus interface loads
Input Ripple 2% peak to peak @ 5 VDC
Output Circuits 01 = 26C31 line driver (RS-422)
02 = OL7272 high voltage line driver
03 = TTL output (single-ended)
04 = ABZ 26C31 line driver, UVW open collector
*Other outputs (or combinations) upon request including open collector ABZ
Incremental Output Format Quadrature with A leading B for CW rotation
Index pulse centered over A for 2500 line count and below
Index pulse true over A and B high for 2500 line count and above
Max Operating Frequency 500 kHz
Symmetry 180º electrical ± 10% typical
Minimum Edge Separation 54° electrical
Commutation Format Three phase 4, 6 or 8 poles (other pole counts upon request)
Commutation Accuracy ±1° mechanical

QR145 Optical Encoder Environmental Specifications

Storage Temperature -40 to 125°C
Operating Temperature -20 to 100°C typical
-20 to 120°C optional
Humidity 98% non-condensing
Vibration 20 g's @ 50 to 500 CPS
Shock 50 g's @ 11 ms duration

QR145 Optical Encoder Mechanical Specifications

Maximum Shaft Speed 8000 RPM
Bore Diameter (Tolerance) 0.1875", 0.250", 0.3125", 0.375", 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 10 mm (+0.0005/-0.0000")
Allowable Shaft Runout 0.007" TIR
Axial Shaft Movement ±0.030"
Housing Carbon fiber composite (case ground via cable)
Housing Volume Resistivity 10⁻² ohm·cm
Termination 15 conductor cable, 28 AWG 18" long
9 conductor cable for non-commutated and TTL outputs
Mounting 1.575", 1.812" bolt circle or size 15 resolver
Moment of Inertia 1.5x10⁻⁴ oz·in·s²
Acceleration 1x10⁵ radians/s²
Accuracy ± 1.0 arc minute
Info & Pricing

More Information & Pricing

To get more information and pricing about this product, please tell us more about what you are looking for below and we can get you what you need:

Consult factory for configurations not shown (e.g. resolution, commutation, etc.).

Download Spec Sheet

Log In

Forgot Password?

Create an account

Create an account to gain access to all of our 3D models!

Create Account

Create an account to gain access to all of our 3D models!

Forgot Password