Froude, Inc. USA
41123 Jo Drive, Novi, MI USA
Froude, Ltd. UK
Blackpole Rd, Worcester WR3 8YB

Eddy Current Dynamometers

Froude's Low Inertia Eddy Current Dynamometer: Dynamically More Responsive

The Air Gap (AG) range of Froude Eddy Current Dynamometers has been designed to be compact, robust and to allow easy maintenance. The narrow yet durable design, small footprint, and the exclusive material and construction technique ensures many years of service. These units are bi-directional, fitted with specialized bearings and extremely accurate (0.25% Full Scale Torque).

Each eddy current dynamometer is fitted with oil injected half couplings at either end of a non-magnetic stainless steel shaft which is supported in grease lubricated, deep groove ball bearings. The non-magnetic shaft means negligible magnetic field dispersion. The dynamometer casing houses twin magnetizing coils that produce a retarding controllable magnetic field that resists the applied torque. Heat generated in this process is dissipated by cooling water.

Rotation of the casing is resisted by a precision strain gauge load cell that gives accurate measurement of total input torque.

Froude Eddy Current Dynamometer
Froude Eddy Current Dynamometer

BEWARE of Froude Imposter Dynos

Only Froude designs/builds the quality dynamometers Froude is well-known for.

Specialized bearings only available from Froude

Tighter tolerances ensure quality and unmatched durability

We go to the extreme for testing our new builds

AG Dynamometer Models

Model
Max Speed (RPM)
Torque Nm (lb.ft)
Power 
kW (BHP)
*Curve Ref
AG30
12,000
95 (70)
30 (40)
Contact Sales
AG30-HS
14,000
95 (70)
30 (40)
Contact Sales
AG80
9,000
160 (118)
80 (105)
Contact Sales
AG80-HS
14,000
160 (118)
80 (105)
Contact Sales
AG200
8,000
800 (590)
200 (270)
Contact Sales
AG350
9,000
1,500 (1,120)
350 (470)
Contact Sales
AG500
7,500
3,000 (2,210)
500 (670)
Contact Sales
AG750
4,000
4,500 (3,320)
750 (1,010)
Contact Sales
AG750HS
5,500
4,500 (3,320)
750 (1,010)
Contact Sales
* Regarding Curve References: Contact sales for appropriate power curve, as multiple configurations may be available depending on your requirements.

Eddy Current (AG) Dynamometer Details

The Air Gap range of Eddy Current Dynamometers has been designed to be compact, robust and to allow easy maintenance.

Main Features:

  • Torque measurement accuracy ±0.25% of full rated torque of dynamometer
  • Speed measurement accuracy ±1 RPM using Froude controller
  • Low inertia 
  • Non-magnetic stainless-steel shaft
  • High balance (G2.5)
  • Low current draw (less than 10 amp for the complete range)
  • Bi-directional 
  • High reliability and durability  
  • Easy maintenance
  • Small footprint
  • Development and production testing of gasoline and diesel engines
  • Engine component test rigs
  • Electric motor testing
  • Educational rigs
  • Gearbox test rigs
  • Cold Temperature/High Altitude Testing

The standard AG dynamometer range extends from 30 kW to 750 kW at speeds up to 12,000 rpm and can absorb power in either direction of rotation.

Torque measurement accuracy is ±0.25% of full rated torque of the dynamometer. The speed is measured by a pulse pickup operating with a 60 tooth wheel and gives accuracy of ±1 rpm.

  • High speed versions up to 14,000 rpm
  • Calibration equipment
  • Shaft bearing thermocouples
  • Cooling water inlet filter
  • Terminal box electrical connector (position on any face of the dyno)
  • Drive / non-drive end water connections (reversibility)
  • Paint color

Information on Froude Eddy Current Dynamometers

Froude AC Dynamometer
Froude Eddy Current Dyno
F Series Hydraulic Dynamometer
High Speed hydraulic dyno
Low Speed hydraulic dynamometer
Go Power Portable Dyno
Froude Dynamometers
Froude dynamometers are renowned the world over as high quality, reliable and accurate. Our test equipment will provide a return on your investment for many years.

Froude, Inc. 
41123 Jo Drive, Novi, MI 48375 USA

Froude, Ltd. 
Blackpole Road, Worcester WR3 8YB 

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