Product Description
In tension control applications that have multiple webs or multiple strands, it is very desirable to match the tension of each web or strand. This is most commonly attained by using a closed loop servo control system which controls current to a braking device through the use of dancer arms, follower arms and in-line tension transducers. The problem with such systems is that each web or strand must be individually controlled, increasing the cost and complicating the system with multiple sensors and power supplies.
Magtrol has developed a system to assure that every brake of a given model designation will be matched, at a predetermined torque and current point, to other brakes of the same model designation regardless of material and manufacturing tolerances. Each brake will be matched at the selected match point to within a tolerance of ±1%. The maximum deviation in torque from brake to brake at any point along their torque/current curve (from 0 torque up to the selected matched torque point) will be less than ±4% of the selected matched torque value. With this level of matching, a system with multiple tension rollers would provide tension consistency within ±1% if set at the matched point with all brakes receiving the same current. The matched point can be any value between 50% and 100% of rated torque, which allows the brakes to be optimized for specific applications. Unless otherwise specified, all brakes are matched at 100 rpm.
Typical vs. Matched Brakes
All single Magtrol Hysteresis Brakes can be matched. When ordering, replace the HB in the Hysteresis Brake model number with MHB. For Large Bore Brakes, LB is replaced with MLB.
EXAMPLE: | Standard | Matched |
HB-140-2 | MHB-140-2
|
LB-250M-2 | MLB-250M-2
|
Specifications and Drawings - English
For complete technical specifications and a general dimension drawing, download the data sheet. For detailed dimension drawings. Click on the PDF icon in the table below and a PDF document will open in a new window. (Adobe Acrobat Reader 7.0, or later, is required.)
NOTE: Brakes will be matched at rated torque unless lower match point (to 50% of rated) is requested. Unless otherwise specified, all brakes are matched at 100 rpm.
Model | Minimum Torque at Rated Current (oz·in) | Rated Current (mA) | Maximum Speed (rpm) | Kinetic Power* - 5 Minutes (W) | Kinetic Power* - Continuous (W) | Downloads |
---|
MHB-2.5 | 2.5 | 98 | 20,000 | 20 | 7 | see data sheet |
MHB-10 | 10.0 | 133 | 20,000 | 45 | 12 | pdf |
MHB-38 | 38.0 | 250 | 15,000 | 90 | 25 | pdf |
MHB-50 | 50.0 | 253 | 15,000 | 90 | 23 | pdf |
MHB-140 | 140.0 | 253 | 12,000 | 300 | 75 | pdf |
MHB-250 | 250.0 | 270 | 10,000 | 450 | 110 | pdf |
MHB-450 | 450.0 | 442 | 8,000 | 670 | 160 | pdf |
MHB-750 | 750.0 | 383 | 7,000 | 1,000 | 200 | pdf |
MHB-1750 | 1750..0 | 500 | 6,000 | 1,200 | 350 | pdf |
Kinetic power ratings are maximum values based on limiting coil and/or bearing temperature to approximately 100 ºC, and should not be exceeded. Actual values in service may vary ±50% depending on mounting, ventilation, ambient temperature, etc. **Standard coil voltage is 24 VDC. 90 volt and non-standard coil voltages are available. 12 VDC coils are available on MHB-2.5 through MHB-750 models.
Specifications and Drawings - Metric
For complete technical specifications and a general dimension drawing, download the data sheet. For detailed dimension drawings. Click on the icon in the table below and a PDF document will open in a new window. (Adobe Acrobat Reader 7.0, or later, is required.)
NOTE: Brakes will be matched at rated torque unless lower match point (to 50% of rated) is requested. Unless otherwise specified, all brakes are matched at 100 rpm.
Model | Minimum Torque at Rated Current (N·m) | Rated Current (mA) | Voltage* (VDC) | Maximum Speed (rpm) | Kinetic Power** - 5 Minutes (W) | Kinetic Power** - Continuous (W) | Downloads |
---|
MHB-3M-2 | 0.02 | 145 | 25.0 | 20,000 | 20 | 5 | see data sheet |
MHB-10M-2 | 0.07 | 133 | 24.0 | 20,000 | 45 | 8 | pdf |
MHB-20M-2 | 0.14 | 217 | 26.0 | 20,000 | 50 | 12 | see data sheet |
MHB-50M-2 | 0.35 | 253 | 24.0 | 15,000 | 90 | 23 | see data sheet |
MHB-140M-2 | 1.00 | 253 | 24.0 | 12,000 | 300 | 75 | pdf |
MHB-250M-2 | 1.75 | 270 | 25.9 | 10,000 | 450 | 110 | see data sheet |
MHB-450M-2 | 3.20 | 442 | 22.1 | 8,000 | 670 | 160 | pdf |
MHB-750M-2 | 5.00 | 383 | 23.0 | 7,000 | 1,000 | 200 | pdf |
MHB-1750M-2 | ***13.00 | 600 | 31.2 | 6,000 | 1,200 | 350 | pdf |
*90 bolt and non-standard coil voltages are available. 12 VDC coils are available on HB-3M-2 through HB-450M-2 models. **Kinetic power ratings are maximum values based on limiting coil and/or bearing temperature to approximately 100° C, and should not be exceeded. actual values in service may vary ±50% depending on mounting, ventilation, ambient temperature, ect. ***13 N·m is attainable @ approx. 600 mA. This value may decrease to 12.36 N·m if the brake is powered by any power supply or controller limited to 500 mA.
Applications
Magtrol’s innovative approach to providing the best possible tension control systems available has led to the development of the Matched Torque Hysteresis Brake. This unique ability to provide matched performance characteristics from any number of brakes of like design and rating makes it possible to control a matched group of brakes from a single sensor or in open loop. This assures that the same level of current to each matched brake will result in virtually the same torque from each matched brake.
Magtrol Matched Hysteresis Brake used in a multiple payoff system where one sensor controls tension in the system. Due to specially calibrated matched brakes, it is possible to hold each payoff tension within ±1% at matched point value.
Large Bore Hysteresis Brakes installed in a fiber optic stranding machine to control the tension of the wrapping material.