Dynapar - Rotary Feedback products. Innovation, Customization, Delivery.

Innovation, Customization, Delivery

Dynapar encompasses the broadest line of trusted brands in motion feedback control, including Dynapar encoders and Hengstler brand incremental encoders and absolute rotary encoders, Northstar heavy-duty magneto-resistive and Heavy-Duty optical encoders and high-performance Harowe brand resolvers. Only Dynapar feedback solutions offer these world-class rotary feedback brands from one Global Supplier with 3 day delivery on most models for customer peace of mind.

Joliet Technologies is the preferred Dynapar Integrator for the Chicagoland area.

RIM Tach® 1250 Digital TachometerRIM Tach® 1250 Digital Tachometer

Quick Specs…

  • Accepts shaft diameters up to 8″ – ideal for crane & hoist applications
  • Non-contact design mounts directly on motor frame
  • Double C face can be sandwiched between motor and brake
  • Zero speed sensors are unaffected by grease, salt water, dirt or other common contaminants.

Overview / Design Principle:

The RIM Tach® 1250 is designed for 12.5 inch diameter type C face motor frames and accessory mounts. This tachometer provides precise, reliable speed signals for many monitoring and control applications and is a standard feedback device for AC & DC variable speed drives. The RIM Tach® 1250 is the process industry’s answer to a large thru-shaft option for precise speed control.

Constructed of ductile cast iron, it ensures maximum strength and endurance for possible exposure to acid wash down in pulp and paper applications. The enclosure accommodates both end-of-shaft and thru-shaft mountings and is universally machined to accommodate all sensor modules, regardless of the desired pulse count.

The RIM Tach® 1250 sensor module is engineered to provide a non-contact sensor and electronics in one interchangeable hermetically sealed package. Encapsulated surface mount electronics provide resistance to water, oil, dirt, high temperatures, shock and vibrations and overall harsh environments. The RIM Tach® 1250 can accommodate up to 2048 pulses per revolution and is bidirectional providing square wave outputs. The sensor module is very simple to change, just remove four screws and slide the new module in place.

There are no bearings to fail or requirements for flexible couplings because its magnetized drum assembly is attached directly to the shaft. The mill duty latching connectors are are easy to wire with no need to field solder or to struggle with a crimp pin.

Features and Benefits:

  • Rugged Mill Duty Construction
  • Reliable Magnetoresistive Technology
  • Easy Installation
  • Modular design for fast, easy field service.
  • Resolutions to 2048 PPR – optional Index


NorthStar’s RIM Tach® 1250 digital tachometer provides position and velocity feedback from both AC & DC electric motors, providing precise, reliable speed signals for many monitoring and control applications


Standard Operating Characteristics

Code: Incremental
Pulses per Revolution: 60-2048
Phasing Sense: A leads B for Counter-Clockwise rotation (CCW) viewing encoder-mounted end
Quadrature Phasing: 90° ± 22°
Symmetry: 180° ± 54°
Index: 270° gated to falling B edge


Input Voltage Requirement: Requirements: 5-15 Volts DC, 45 mA typical per sensor module plus line driver load
Output Signals: Line Driver, 150mA source/sink
Frequency Response: 0 – 120kHz Data & Index
Electrical Immunity: 2kV ESD, Reverse Polarity, Short Circuit
Connector: 10 pin industrial duty latching, sealed NEMA 4 &12, IP65


Shaft Speed: 5,000 RPM (J or K wheels);
3600 RPM (L wheels)
Mounting Configuration: 12.5” face mount for NEMA MG1 standards
Housing Material: Cast Iron/Stainless Steel
Acceleration Rate: 3600 rpm/sec max
Shaft Length Required: 3.0” min
Allowable Shaft End-Play: ± 0.050”
Allowable Shaft Runout: 0.003” TIR


Operating Temperature Range: -40°C to +80°C
Storage Temperature Range: -40°C to +120°C
Humidity: to 98% RH (non-condensing)
Shock (Sensor Module): 1 meter drop test, 30 G’s Min
Vibration: 18 G’s @ 5-2000 Hz spectrum

Available Specifications:

Related Products & Resources:

For additional information or to receive a full-line catalog, contact your Dynapar representative at 1.800.873.8731 or visit their web site at: www.dynapar.com
Headquarters:1675 Delany Road • Gurnee, IL 60031-1282 • USA
Phone: 1.847.662.2666
Fax: 1.847.662.6633
Email: custserv@dynapar.com or dynapar.techsupport@dynapar.com
© 2009 Dynapar Corp. Printed in U.S.A. • Feedback Quick Reference Guide P/N# N-FLB130 (11/09) 5M

Call Joliet Technologies TODAY 

If you have any questions concerning Dynapar products, feel free to contact us:
Phone (815) 725-9696,
Toll Free (866) 492-9888,
Fax (815) 725-9393 or
E-mail info@joliettech.com

Joliet Technologies custom packages, integrates and engineers AC Variable Frequency Drives (VFD), DC Variable Speed Drives (VSD) and AC Drive Controllers using top of the line manufacturers, like ABB, Emerson-Control Techniques, Siemens and Saftronics (Fincor). Our custom drive packages are built to your specifications for your application. We specialize in large horsepower drive systems (500Hp and above). Call us at (815) 725-9696 or fax us at (815) 725-9393 or e-mail us or fill out an RFQ with your requirements. Serving the greater Chicagoland area and the World.