Hysteresis Brakes and Clutches - Electro

HYSTERESIS BRAKES
AND CLUTCHES
PROVIDING TECHNICAL SOLUTIONS TO YOUR TENSION CONTROL PROBLEMS
Frictionless
n
Longer Expected Life
n
Superior Repeatability
n
Less Maintenance
n
Less Downtime
Pioneers in Hysteresis Torque Control
Founded in 1953, Magtrol, Inc. pioneered the technology of applying the principles of magnetic hysteresis to meet the critical
needs for reliable, smooth and adjustable torque control. This pioneering effort led to the development of Magtrol’s Hysteresis
Brake and Clutch products, which feature superior torque repeatability, longer expected life, a broad speed range and lower
operating costs. A leading edge company, Magtrol serves a wide array of torque and tension control applications and continues to
develop innovations in hysteresis technology. This catalog features our standard English brake and clutch products. A complete
line of metric hysteresis devices are also available. For more information, please refer to Magtrol’s Hysteresis Brake Metric
Product Guide which can be accessed from our web site at http://www.magtrol.com/brochures/metricbrake.pdf.
Principles & Advantages of Hysteresis Brakes .... page 3
Hysteresis Brakes ............................................... pages 4-7
Hysteresis Clutches......................................... pages 8-10
Matched Brakes and Applications ............ pages 11-13
Permanent Magnet Brakes & Clutches..... pages 14–15
How to Select a Brake or Clutch ................ pages 16-17
Special Designs and Modifications .................. page 18
Options and Accessories .................................. page 19
Hysteresis Principles
PRINCIPLES OF HYSTERESIS
Overview
Control
The hysteresis effect in magnetism is applied to torque control
by the use of two basic components –a reticulated pole structure
and a specialty steel rotor/shaft assembly–fastened
together but not in physical contact. Until the
field coil is energized, the drag cup can
spin freely on the ball bearings. When a
magnetizing force from either a field
coil or magnet is applied to the pole
structure, the air gap becomes
a flux field. The rotor is
magnetically restrained,
ROTOR
providing a braking (Drag Cup)
action between the pole
structure and rotor.
In an electrically operated Hysteresis Brake, adjustment and
control of torque is provided by a field coil. This allows for
complete control of torque by adjusting DC
current to the field coil.
POLE STRUCTURE
Adjustability from a
minimum value (bearing
SHAFT
drag) to a maximum value
of rated torque is possible.
Additional torque in the
BALL BEARINGS
range of 15-25% above
rated torque may be
FIELD COIL
available on some brakes.
HUB
Because torque is produced
strictly through a magnetic
air gap, without the use
of friction or shear forces,
Magtrol Hysteresis Brakes
provide absolutely smooth,
infinitely controllable torque loads,
independent of speed, and they operate quietly without any
physical contact of interactive members. As a result, with the
exception of shaft bearings, no wear components exist.
The amount of braking
torque transmitted by the
brake is proportional to the
amount of current flowing
through the field coil. The
AIR GAP
direction of current flow
(polarity) is of no consequence
to the operation of the brake. For optimum
torque stability, a DC supply with current regulation is
recommended. This will help to minimize torque drift attributable
to changes in coil temperature and in-line voltage, which can result
in changes in coil current, and consequently, in torque.
ADVANTAGES OF HYSTERESIS DEVICES
Long, Maintenance-Free Life
Superior Torque Repeatability
Magtrol Hysteresis Brakes produce torque strictly through
a magnetic air gap, making them distinctly different from
mechanical-friction and magnetic particle devices. Because
hysteresis devices do not depend on friction or shear forces
to produce torque, they do not suffer the problems of wear,
particle aging, and seal leakage. As a result, hysteresis devices
typically have life expectancies many times that of friction and
magnetic particle devices.
Because torque is generated magnetically without any
contacting parts or particles, Hysteresis Brakes provide
superior torque repeatability. Friction and magnetic particle
devices are usually subject to wear and aging with resultant loss
of repeatability. Magtrol devices will repeat their performance
precisely, to ensure the highest level of process control.
Life Cycle Cost Advantages
Magtrol hysteresis devices offer the highest slip speed range
of all electric torque control devices. Depending on size,
kinetic power requirements and bearing loads, many Magtrol
Brakes can be operated at speeds in excess of 10,000 rpm. In
addition, full torque is available even at zero slip speed and
torque remains absolutely smooth at any slip speed.
While the initial cost of hysteresis devices may be the same
or slightly more than that of their counterparts, the high
cost of replacing, repairing and maintaining friction and
magnetic particle devices often makes hysteresis devices
the most cost-effective means of tension and torque control
available.
Operational Smoothness
Because they do not depend on mechanical friction or particles
in shear, Hysteresis Brakes are absolutely smooth at any slip
ratio. This feature is often critical in wire drawing, packaging
and many other converting applications.
3
Broad Speed Range
Excellent Environmental Stability
Magtrol hysteresis devices can withstand significant variation
in temperature and other operating conditions. In addition,
because they have no particles or contacting active parts,
Hysteresis Brakes are extremely clean. Magtrol devices are
used in food and drug packaging operations, in clean rooms,
and environmental test chambers.
M AGTROL
HB Series
Hysteresis Brakes
HB Series
Data Sheet
DESCRIPTION
Pure Hysteresis Brakes produce torque strictly through a
magnetic air gap without the use of magnetic particles or
friction components. This method of braking provides far
superior operating characteristics (smoother torque, longer life,
superior repeatability, high degree of controllability, and less
maintenance and down time) which make them the preferred
choice for precise tension control during the processing of
nearly any material, web or strand.
RATINGS
Number 1 Coil
Number 2 Coil
Number 3 Coil
Minimum
Torque
Res. at
Res. at
Res. at
Watts Rated
Watts Rated
Watts
Brake
at Rated Rated
25°C
VDC
25°C
VDC
25°C
VDC
(Nom.) Current
(Nom.) Current
(Nom.)
Model
Current Current ±10%
±10%
±10%
oz·in
mA
At Rated I
mA
At Rated I
mA
At Rated I
Ω
Ω
Ω
HB-2.5
2.5
37 2430.0
90.0
3.3
146
171
25.0
3.7
333
36.0
12.0
4.0
HB-8
8
38 1900.0
72.0
2.7
133
180
24.0
3.2
270
45.0
12.0
3.3
HB-16
16
45 2300.0 103.0
4.6
192
125
24.0
4.6
375
32.0
12.0
4.5
HB-32
32
67 1350.0
90.0
6.1
250
105
26.3
6.6
530
22.5
12.0
6.4
HB-50
50
67 1350.0
90.0
6.0
253
95
24.0
6.1
480
25.0
12.0
5.8
HB-140
140
60 1537.0
93.0
5.6
253
95
24.0
6.1
504
23.2
11.7
5.9
HB-250
250
89
957.0
84.9
7.5
270
96
25.9
7.0
533
24.0
12.8
6.8
HB-450
450
116
805.0
93.6
10.9
442
50
22.1
9.8
703
19.5
13.7
9.6
HB-750
750
107
845.0
90.0
9.6
383
60
23.0
8.8
N/A
HB-840
840
160
562.5
90.0
14.4
600
40
24.0
14.4
1230
9.8
12.0
14.8
HB-1750
1750
149
604.0
90.0
13.4
500
52
26.0
13.0
N/A
HB-3500
3500
298
302.0
90.0
26.8
1000
26
26.0
26.0
N/A
Brake
Model
HB-2.5
HB-8
HB-16
HB-32
HB-50
HB-140
HB-250
HB-450
HB-750
HB-840
HB-1750
HB-3500
Maximum
Speed
rpm
20,000
20,000
20,000
15,000
15,000
12,000
10,000
8,000
7,000
6,000
6,000
6,000
Kinetic Power Rating*
Drag Torque**
watts
De-energized
5 Minutes
Continuous
oz·in
20
5
0.05
60
15
0.10
75
20
0.10
90
25
0.20
90
23
0.20
300
75
0.70
450
110
1.00
670
160
2.00
1,000
200
7.00
1,340
300
4.00
2,400
350
13.00
4,800
600
19.20
External
Inertia
lb·in·s²
3.8 × 10-6
3.3 × 10-5
5.6 × 10-5
8.6 × 10-5
1.478 × 10-4
9.1 × 10-4
2.75 × 10-3
6.55 × 10-3
1.283 × 10-2
1.31 × 10-2
5.28 × 10-2
1.056 × 10-1
Angular
Model Weight
Acceleration
rad/s²
lb
41,100
0.24
15,200
0.49
17,900
0.65
23,300
1.06
21,000
1.72
9,620
4.06
5,680
7.73
4,290
12.90
3,450
28.30
4,010
26.30
2,070
54.00
2,070
110.00
* Kinetic power ratings are maximum values based on limiting coil and/or bearing temperature to approximately 100ºC, and should not
be exceeded. Actual values in service may vary ±50% depending on mounting, ventilation, ambient temperature, etc.
** Drag torque is based on 1000 rpm shaft speed.
4
M AGTROL
Dimensions
HB Series
BRAKE DIMENSIONS
E
D
N
M
NOTE: All dimensions are in English
units (inches). Metric brakes are
available as a separate product
line—please refer to our Metric
Product Guide available online at
http://www.magtrol.com/brochures/
metricbrake.pdf
N
M
ØA ØC ØB
ØB
F
J
K (3) Mounting Holes - equally spaced
I
ØL Bore Circle
Brake
Model
HB-2.5
HB-8
HB-16
HB-32
HB-50
HB-140
HB-250
HB-450
HB-750
HB-840
HB-1750
HB-3500
H
G
ØA
ØB
ØC
D
E
1.250
1.800
1.970
2.155
2.360
3.624
4.437
5.420
6.220
5.485
8.900
8.900
0.1250
0.1875
0.1875
0.2500
0.2500
0.3750
0.5000
0.5000
0.6250
0.5000
1.0000
1.0000
0.375
0.500
0.500
0.625
0.625
0.875
1.125
1.125
1.375
*
2.000
*
0.012
0.021
0.015
0.025
0.033
0.025
0.035
0.035
0.035
*
0.056
*
0.030
0.096
0.096
0.094
0.096
0.140
0.156
0.156
0.163
*
0.250
*
F
G
0.73 1.564
0.82 2.120
0.81 2.109
1.25 3.000
1.56 3.000
1.53 3.968
1.98 4.718
2.06 5.156
2.87 6.930
4.13 7.750
3.00 8.312
6.00 12.460
H
I
0.29
0.50
0.51
0.56
0.56
1.00
1.06
1.06
1.50
1.00
2.04
2.04
0.94
1.00
0.95
1.69
1.69
2.00
2.53
2.87
3.74
*
4.18
*
J
K
L
M
0.29 #4-40 × 0.16 0.750
0.50 #4-40 × 0.19 0.687
0.55 #4-40 × 0.19 0.750
0.63 #6-32 × 0.25 0.906
0.63 #6-32 × 0.25 0.906
0.80 #8-32 × 0.37 1.500
0.93 #10-32 × 0.50 1.750
1.03 #10-32 × 0.37 1.750
1.50
1⁄4-20 × 0.44 2.750
*
*
1.00
1.79
1⁄4-20 × 0.50 3.000
*
*
2.04
N
----0.375 0.025
0.375 0.025
0.375 0.025
0.375 0.025
0.625 0.060
0.625 0.060
0.625 0.060
0.750 0.060
0.625 0.060
keyway
keyway
Solid
Model
3
3
3
3
3
3
3
3
3
3
3
3
* HB-840 and HB-3500 are double brake assemblies that require base mounting. See base mounting under “Brake Options” for details.
Magtrol manufactures double brakes to increase torque capability. For more information and a drawing, contact Magtrol.
PILLOW BLOCK DIMENSIONS
ØU
V (Drill Thru and
T
Counter-bore for
3 Socket Head
Cap Screws)
ØW (holes thru)
S
R
Q
P
X
O
Pillow
Block
Model
4736
4702
4703
4705
4705
4711
4714
4717
4720
4722
For
Brake
Model
HB-2.5
HB-8
HB-16
HB-32
HB-50
HB-140
HB-250
HB-450
HB-750
HB-1750
O
1.75
2.50
2.50
2.50
2.50
4.00
4.00
4.62
5.25
7.50
P
1.500
2.125
2.125
2.125
2.125
3.500
3.500
4.000
4.500
6.500
Q
0.31
0.37
0.37
0.37
0.37
0.37
0.37
0.50
0.75
1.00
Y
R
1.000
1.437
1.437
1.437
1.437
2.000
2.375
3.000
3.250
5.000
S
1.500
2.120
2.120
2.120
2.120
3.190
3.690
4.310
5.125
7.000
T
ØU
0.25
0.38
0.38
0.38
0.38
0.50
0.50
0.56
0.75
1.00
0.750
0.687
0.750
0.906
0.906
1.500
1.750
1.750
2.750
3.000
V
ØW
#4-40
#4-40
#4-40
#6-32
#6-32
#8-32
#10-32
#10-32
1⁄4-20
1⁄4-20
0.125
0.201
0.201
0.201
0.201
0.201
0.201
0.201
0.343
0.328
X
0.125
0.187
0.187
0.187
0.187
0.250
0.250
0.250
0.375
0.500
Y
0.25
0.38
0.38
0.38
0.38
0.50
0.50
0.50
0.75
1.00
Solid
Model
3
3
3
3
3
3
3 Solid 3-D models are available for this unit by contacting Magtrol Customer Service.
5
M AGTROL
Applications
HB Series
Slitter Blades
Idler Rollers
Magtrol Hysteresis Brakes offer
frictionless, non-breakaway
force for tensioning materials
during slitting and many
other material processing
operations.
Brake Roller
Ribbons
Slitting
Tension Brake
Unwind
Tension Holding
Hysteresis Brake
Motor
Hysteresis Brake
Hysteresis Clutch
Ball Screw
Load
Magtrol Hysteresis Brake used for holding of
backdriving load.
Motor
Motor
Ball Screw
Load
Hysteresis Brakes
Magtrol Hysteresis Brakes are widely
used in load simulation applications for
life testing on electric motors, actuators,
small gas engines, gearboxes, and many
other rotating devices and assemblies.
Motors
6
M AGTROL
Applications
HB Series
Magtrol Hysteresis Brakes provide
precise control of wire tension during
wind, hook and cut operation of high
speed automated winding machines.
Control Panel
Armature
Hysteresis
Brake
Hysteresis
Brake
Wire
Magazine
Wire
Magazine
Hysteresis Brakes
Transformer and coil winding operations employing
Hysteresis Brakes in open loop control for maintaining
precise tension during winding process.
Wound Coil
Wire Spool
Regardless of control scheme (dancer roll, follower arm, photo or
ultrasonic sensors), Magtrol Hysteresis Brakes provide the ultimate in
tension control devices.
Follower Arm
Holdback
Hysteresis
Brake
Photo Eye
Gap
Hysteresis
Brake
Potentiometer
Controller/
Power Supply
Controller/
Power Supply
7
M AGTROL
HCS Series
Hysteresis Clutches
HCS Series
Data Sheet
DESCRIPTION
Like Magtrol’s Hysteresis Brake, the Hysteresis Clutch
develops torque strictly through a magnetic air gap, ensuring
an absolutely smooth transmission of torque from the drive unit
to the driven element. Designed to be powered without the use
of brushes or slip rings, and being a pure hysteresis device that
does not rely on friction elements or magnetic particles, there is
never any fear of contamination due to wear particles or leaky
seals. This makes Magtrol Hysteresis Clutches and Brakes ideal
for use in food processing and clean room environments.
RATINGS
Number 1 Coil
Number 2 Coil
Number 3 Coil
Minimum
Torque
Res. at
Res. at
Res. at
Clutch
Watts Rated
Watts Rated
Watts
at Rated Rated
25°C
VDC
25°C
VDC
25°C
VDC
Model
(Nom.) Current
(Nom.) Current
(Nom.)
Current Current ±10%
±10%
±10%
oz·in
mA
At Rated I
mA
At Rated I
mA
At Rated I
Ω
Ω
Ω
HCS-8
8
38
1,900
72
2.5
197
142.0
28
5.51
361
33
12
4.3
HCS-16
16
45
2,300
103
4.5
192
125.0
24
4.61
375
32
12
4.5
HCS-32
32
71
1,500
106
7.5
332
72.5
24
8.00
667
18
12
8.0
HCS-120
120
79
1,200
95
7.5
200
120.0
24
4.80
400
30
12
4.8
HCS-210
210
123
751
93
11.4
375
75.0
28
10.50
736
19
14
10.2
HCS-420
420
162
517
84
13.6
460
52.0
24
11.00
914
30
12
10.8
Clutch
Model
HCS-8
HCS-16
HCS-32
HCS-120
HCS-210
HCS-420
Maximum
Speed
rpm
3,600
3,600
3,600
3,600
3,600
3,600
Kinetic Power Rating*
Drag Torque**
watts
De-energized
5 Minutes
Continuous
oz·in
60
15
0.1
75
20
0.1
90
25
0.1
300
75
0.7
450
110
1.0
670
160
2.0
External
Inertia
lb·in·s²
3.3 × 10-5
5.6 × 10-5
8.6 × 10-5
9.1 × 10-4
2.75 × 10-3
6.55 × 10-3
Angular
Model Weight
Acceleration
rad/s²
lb
15,200
0.33
17,900
0.94
23,300
1.56
8,240
4.78
4,700
9.15
4,010
19.50
* Kinetic power ratings are maximum values based on limiting coil and/or bearing temperature to approximately 100ºC, and should not
be exceeded. Actual values in service may vary ±50% depending on mounting, ventilation, ambient temperature, etc.
** Drag torque is based on 1000 rpm shaft speed.
8
M AGTROL
Dimensions
HCS Series
CLUTCH DIMENSIONS
Lead Wires (2)
12” Lg. Standard
Coil Assembly
Output Shaft
Input Shaft
M
N
ØA
ØD
ØE
ØB
ØC
G
F
K (3) Mounting Holes - equally spaced
ØL Bore Circle
Clutch
Model
HCS-8
HCS-16
HCS-32
HCS-120
HCS-210
HCS-420
I
J
ØA
ØB
ØC
ØD
ØE
F
1.88
2.00
2.09
3.62
4.47
5.72
0.1875
0.1875
0.2500
0.3750
0.5000
0.7500
0.375
0.375
0.500
0.625
0.750
1.000
0.8750
0.8750
1.1250
1.6250
2.1654
2.6772
1.56
1.67
1.67
3.20
3.96
5.07
0.100
0.100
0.212
0.312
0.312
0.375
G
H
I
0.897 0.69
1.062 0.75
1.603 * 0.87
1.430 1.00
1.912 1.10
2.449 1.25
NOTE: All dimensions are in
English units (inches).
H
J
1.156
1.321
2.006
2.625
2.975
3.811
K
0.750 #4-40 × 0.19
0.875 #6-32 × 0.22
0.740 #6-32 × 0.28
0.952 #10-32 × 0.25
1.312 #10-32 × 0.39
1.686 #10-32 × 0.38
ØL
M
N
1.250
1.250
1.437
2.750
3.000
3.875
0.37
0.37
0.37
0.50
-----
0.02
0.02
0.03
0.06
-----
* HCS-32 shaft is stepped up to 0.3750/0.3745 inches diameter, 0.59 inches from end of shaft, for R6 bearing. Please contact Magtrol if
additional information is required.
PILLOW BLOCK DIMENSIONS
ØU
Bore Circle
Y
V (Drill Thru and
Counter-bore for
3 Socket Head
Cap Screws equally spaced)
NOTE:
Mounting
screws are
supplied with
each pillow
block kit,
For
Clutch
Model
HCS-8
HCS-16
HCS-32
HCS-120
HCS-210
HCS-420
BB
Y
Bearing
S
R
T
Q
P
O
X
Z
ØW
(4) Thru Holes
REAR VIEW
Pillow
Block
Model
4742
4744
4753
4755
4760
4759
AA
O
P
Q
R
S
T
2.625
2.625
2.625
4.250
5.000
6.000
2.250
2.250
2.250
3.750
4.500
5.500
0.38
0.38
0.38
0.50
0.50
0.50
1.437
1.437
1.437
2.000
3.000
3.500
2.25
2.25
2.31
3.62
4.88
5.88
1.94
1.94
2.06
3.20
4.25
5.12
SIDE VIEW
ØU
V
ØW
FRONT VIEW
X
1.250 #4-40 0.201 1.531
1.250 #6-32 0.201 1.696
1.437 #6-32 0.201 2.381
2.750 #10-32 0.204 3.125
3.000 #10-32 0.266 3.470
3.875 #10-32 0.266 4.436
Y
Z
AA
BB
Screw Bearing
Number Number
0.38
0.38
0.38
0.50
0.50
0.62
1.906
2.071
2.756
3.625
3.970
5.061
1.156
1.321
2.006
2.625
2.970
3.811
1.88
1.88
1.88
3.25
4.00
5.00
50-5729
50-5707
50-5707
50-5731
50-5770
50-5770
50-6432
50-6432
50-6460
50-6460
50-6192
50-6432
If Magtrol pillow block kits are not used, the clutch must be piloted and adequately supported on the input bearing.
The mounting face must be square to the centerline of the input and output shafts to within 0.001” per inch and the
output shaft must be supported using the bearing listed in the table above.
9
M AGTROL
Applications
HCS Series
Closed-loop winding tension and speed
control – Hysteresis Clutch on powered
rewind. Tension controlled by means of
dancer roller with potentiometer, clutch
and controller
Hysteresis
Clutch
Dancer Roll
Potentiometer
Motor
Controller/
Power Supply
Hysteresis
Clutches
Magtrol Hysteresis Clutches provide
precise control of torque for
capping,bolting and other screw
applications. Their clean particlefree nature eliminates fear of
contamination, making them ideal
for use in food processing and clean
room environments.
Bottles
with
caps
Bottles
without
caps
Hysteresis Brake
Hysteresis Clutch
Torque limiting Hysteresis Clutch arrangement prevents
over torque and provides precise, stable and smooth
application of torque.
Ball Screw
Load
Ball Screw
Motor
Load
M AGTROL
10
Motor
MHB Series
MatchedHysteresisBrakes
MHB Series
Data Sheet
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.
RATINGS
Number 1 Coil
Number 2 Coil
Number 3 Coil
Minimum
Torque
Res. at
Res. at
Res. at
Watts Rated
Watts Rated
Watts
Brake
at Rated Rated
25°C
VDC
25°C
VDC
25°C
VDC
(Nom.) Current
(Nom.) Current
(Nom.)
Model
Current Current ±10%
±10%
±10%
oz·in
mA
At Rated I
mA
At Rated I
mA
At Rated I
Ω
Ω
Ω
MHB-2.5
2.5
30
2724
82.0
2.47
98
262
26.0
2.53
353
34.0
13.0
4.00
MHB-10.5
11
52
1803
95.0
5.00
201
113
23.0
4.57
317
43.0
14.0
4.35
MHB-38
38
79
1052
83.0
6.60
250
105
26.3
6.60
461
26.7
12.3
5.70
MHB-50
50
67
1350
90.0
6.00
253
95
24.0
6.10
480
25.0
12.0
5.80
MHB-140
140
60
1537
93.0
5.60
253
95
24.0
6.10
504
23.2
11.7
5.90
MHB-250
250
89
957
84.9
7.50
270
96
25.9
7.00
533
24.0
12.8
6.80
MHB-450
450
116
805
93.6
10.90
442
50
22.1
9.80
703
19.5
13.7
9.60
MHB-750
750
107
845
90.0
9.60
383
60
23.0
8.80
N/A
MHB-1750
1750
149
604
90.0
13.40
500
52
26.0
13.00
N/A
Brake
Model
MHB-2.5
MHB-10.5
MHB-38
MHB-50
MHB-140
MHB-250
MHB-450
MHB-750
MHB-1750
Maximum
Speed
rpm
20,000
20,000
15,000
15,000
12,000
10,000
8,000
7,000
6,000
Kinetic Power Rating*
Drag Torque**
watts
De-energized
5 Minutes
Continuous
oz·in
20
7
0.05
60
15
0.10
90
25
0.20
90
23
0.20
300
75
0.70
450
110
1.00
670
160
2.00
1,000
200
7.00
2,400
350
13.00
External
Inertia
lb·in·s²
3.8 × 10-6
3.3 × 10-5
8.6 × 10-5
1.478 × 10-4
9.1 × 10-4
2.75 × 10-3
6.55 × 10-3
1.283 × 10-2
5.28 × 10-2
Angular
Model Weight
Acceleration
rad/s²
lb
41,100
0.24
19,900
0.49
27,600
1.06
21,000
1.72
9,620
4.06
5,680
7.73
4,290
12.90
3,450
28.30
2,070
54.00
* Kinetic power ratings are maximum values based on limiting coil and/or bearing temperature to approximately 100ºC, and should not
be exceeded. Actual values in service may vary ±50% depending on mounting, ventilation, ambient temperature, etc.
** Drag torque is based on 1000 rpm shaft speed.
11
M AGTROL
Dimensions
MHB Series
BRAKE DIMENSIONS
E
D
N
M
NOTE: All dimensions are in English
units (inches). Metric brakes are
available as a separate product
line—please refer to our Metric
Product Guide available online at
http://www.magtrol.com/brochures/
metricbrake.pdf
N
M
ØA ØC ØB
ØB
F
J
K (3) Mounting Holes - equally spaced
I
ØL Bore Circle
Brake
Model
MHB-2.5
ØA
H
G
ØB
ØC
D
E
F
G
H
I
J
K
L
M
N
---
---
1.250 0.1250 0.375 0.010 0.030
0.73
1.564
0.30
0.94
0.29
#4-40 × 0.16 0.750
MHB-10.5 1.800 0.1875 0.500 0.015 0.096
0.82
2.159
0.50
1.00
0.55
#4-40 × 0.19 0.687 0.375 0.025
MHB-38
2.155 0.2500 0.625 0.032 0.096
1.25
3.000
0.56
1.69
0.63
#6-32 × 0.25 0.906 0.375 0.025
MHB-50
2.360 0.2500 0.625 0.033 0.096
1.56
3.000
0.56
1.69
0.63
#6-32 × 0.25 0.906 0.375 0.025
MHB-140
3.624 0.3750 0.875 0.025 0.140
1.53
3.968
1.00
2.00
0.80
#8-32 × 0.37 1.500 0.625 0.060
MHB-250
4.437 0.5000 1.125 0.035 0.156
1.98
4.718
1.06
2.53
0.93 #10-32 × 0.50 1.750 0.625 0.060
MHB-450
5.420 0.5000 1.125 0.035 0.156
2.06
5.156
1.06
2.87
1.03 #10-32 × 0.37 1.750 0.625 0.060
MHB-750
6.220 0.6250 1.375 0.035 0.163
2.87
6.930
1.50
3.74
1.50
1⁄4-20 × 0.44 2.750 0.750 0.060
MHB-1750 8.900 1.0000 2.000 0.056 0.250
3.00
8.312
2.04
4.18
1.79
1⁄4-20 × 0.50 3.000
Solid
Model
3
3
3
keyway
PILLOW BLOCK DIMENSIONS
ØU
V (Drill Thru and
T
Counter-bore for
3 Socket Head
Cap Screws)
ØW (holes thru)
S
R
Q
P
X
O
Y
Pillow
Block
Model
4736
MHB-2.5
1.75
1.500
0.31
1.000
4702
MHB-10.5
2.50
2.125
0.37
1.437
4705
MHB-38
2.50
2.125
0.37
4705
MHB-50
2.50
2.125
0.37
4711
MHB-140
4.00
3.500
4714
MHB-250
4.00
4717
MHB-450
4720
MHB-750
4722
MHB-1750
For Brake
Model
O
P
Q
R
S
V
ØW
X
Y
Solid
Model
T
ØU
1.500
0.25
0.750
#4-40
0.125
0.125
0.25
3
2.120
0.38
0.687
#4-40
0.201
0.187
0.38
3
1.437
2.120
0.38
0.906
#6-32
0.201
0.187
0.38
3
1.437
2.120
0.38
0.906
#6-32
0.201
0.187
0.38
3
0.37
2.000
3.190
0.50
1.500
#8-32
0.201
0.250
0.50
3.500
0.37
2.375
3.690
0.50
1.750 #10-32
0.201
0.250
0.50
4.62
4.000
0.50
3.000
4.310
0.56
1.750 #10-32
0.201
0.250
0.50
5.25
4.500
0.75
3.250
5.125
0.75
2.750
1⁄4-20
0.343
0.375
0.75
7.50
6.500
1.00
5.000
7.000
1.00
3.000
1⁄4-20
0.328
0.500
1.00
3
3 Solid models are available for this unit by contacting Magtrol Customer Service.
12
M AGTROL
Applications
MHB Series
TYPICAL BRAKES VS. MATCHED
Typical
Matched Brakes
Brake
Power
Supply
Transducer
op
t
ic
s
nd
ra
St
Brake
Power
Supply
Fi b
er
Transducer
Brake
Brake
Power
Supply
Transducer
Matched Large Bore
Hysteresis Brakes
Brake
Brake
Brake
Power
Supply
Hysteresis Brakes, installed in a fiber optic
stranding machine to control the tension of
the wrapping material.
Transducer
Multiple Pay-Off System
Magtrol
Matched
Hysteresis Brakes used in
a multiple pay-off system
where one sensor controls
tension in the system. Due
to specially calibrated
“matched” brakes, it is
possible to hold each
pay-of f tension within
±1% at matched point
value.
Extruder
Wires or
Thread
Matched
Hysteresis Brake
Spool
Follower Arm
Pot
(Enlarged View)
13
Controller/
Power Supply
Matched
Hysteresis
Brakes
M AGTROL
HPM Series Permanent
MagnetBrakes&Clutches
HPM Series
Data Sheet
DESCRIPTION
Magtrol Hysteresis Permanent Magnet Brakes and Clutches are
ideal in applications where electrical power cannot be provided
to a brake or clutch coil. While best suited to applications
where fixed torque is to be applied, adjustable units can be
made specifically tailored to the application. While typically
provided as brake units, by the addition of an input shaft, the
same unit can be used as a clutch. In a clutch application, the
pole/case member becomes the drive element, and the rotor/
shaft assembly becomes the driven element of the clutch
with torque being transmitted through the magnetic air-gap.
Magtrol Hysteresis Permanent Magnet devices provide all the
superior operating characteristics of smooth operation, precise
repeatability and long life inherent in our standard Hysteresis
Brakes and Clutches.
PERMANENT MAGNET BRAKE RATINGS
Brake
Model
HPM-2.5
Rated
Torque*
oz·in
Maximum
Speed**
rpm
Kinetic Power Ratings
watts
5 Minutes Continuous
External
Inertia
lb·in·s²
Angular
Acceleration
rad/s²
Model
Weight
lb
2.5
10,820
20
7
3.8 × 10-6
41,100
0.17
HPM-8
8
10,140
60
15
3.3 × 10-5
15,200
0.49
HPM-16
16
6,340
75
20
5.6 × 10-5
17,900
0.65
HPM-32
32
3,800
90
25
8.6 × 10-5
23,300
1.06
HPM-120
120
3,380
300
75
9.1 × 10-4
8,240
4.06
HPM-210
210
2,900
450
110
2.75 × 10-3
4,770
7.73
PERMANENT MAGNET CLUTCH RATINGS
Clutch
Model
HPMC-2.5
Rated
Torque*
oz·in
Maximum
Speed**
rpm
Kinetic Power Ratings
watts
5 Minutes Continuous
External
Inertia
lb·in·s²
Angular
Acceleration
rad/s²
Model
Weight
lb
2.5
10,820
20
7
3.8 × 10-6
41,100
0.17
HPMC-8
8
10,140
60
15
3.3 × 10-5
15,200
0.49
HPMC-16
16
6,340
75
20
5.6 × 10-5
17,900
0.65
HPMC-32
32
3,800
90
25
8.6 × 10-5
23,300
1.06
HPMC-120
120
3,380
300
75
9.1 × 10-4
8,240
4.06
HPMC-210
210
2,900
450
110
2.75 × 10-3
4,770
7.73
* Permanent Magnet Brakes can be charged at factory to produce lower torque if desired.
** Maximum speed listed will produce 5-minute kinetic power rating at rated torque.
14
M AGTROL
Dimensions
HPM Series
PERMANENT MAGNET BRAKE DIMENSIONS
E
D
N
M
M
N
ØA ØC ØB
ØB
F
J
K (3) Mounting Holes - equally spaced
I
ØL Bore Circle
Brake
Model
HPM-2.5
HPM-8
HPM-16
HPM-32
HPM-120
HPM-210
H
G
ØA
ØB
ØC
D
E
F
G
H
I
J
K
ØL
M
N
1.250
1.750
1.970
2.250
3.625
4.437
0.1250
0.1875
0.1875
0.2500
0.3750
0.5000
0.375
0.500
0.500
0.625
0.875
1.125
0.015
0.015
0.015
0.025
0.025
0.035
0.030
0.060
0.096
0.094
0.130
0.156
0.840
0.915
0.812
0.865
0.985
2.410
1.564
2.109
2.109
2.431
3.490
4.693
0.290
0.500
0.515
0.562
0.910
1.062
0.940
0.953
0.946
1.125
1.654
2.510
0.290
0.584
0.545
0.625
0.800
0.930
#4-40 × 0.16
#4-40 × 0.16
#4-40 × 0.25
#6-32 × 0.20
#8-32 × 0.25
#10-32 × 0.38
0.750
0.687
0.750
0.906
1.500
1.750
--0.375
0.375
0.375
0.625
0.625
--0.025
0.025
0.030
0.060
0.060
Solid
Model
3
3
PERMANENT MAGNET CLUTCH DIMENSIONS
E
D
N
M
M
N
ØA ØC ØB
ØB
F
J
K (3) Mounting Holes - equally spaced
I
ØL Bore Circle
Clutch
Model
HPMC-2.5
HPMC-8
HPMC-16
HPMC-32
HPMC-120
HPMC-210
ØA
1.250
1.750
1.970
2.250
3.500
4.437
ØB
0.1250
0.1875
0.1875
0.2500
0.3750
0.5000
H
G
ØC
D
E
F
G
H
I
J
1.059
1.000
1.000
1.500
2.000
2.250
0.032
0.032
0.032
0.032
0.032
0.062
0.250
0.312
0.312
0.375
0.375
0.500
0.840
0.915
0.812
0.865
1.150
2.410
1.803
2.375
2.350
2.719
3.732
5.060
0.290
0.500
0.515
0.562
1.000
1.062
1.224
1.295
1.290
1.532
1.932
3.067
0.290
0.584
0.545
0.625
0.800
0.935
K
#4-40
#4-40
#4-40
#6-32
#8-32
#10-32
ØL
M
0.750
0.687
0.750
0.906
1.500
1.750
--0.375
0.375
0.375
0.625
0.625
Solid
Model
--3
0.025
3
0.025
0.030
0.060
0.060
N
3 Solid models are available for this unit by contacting Magtrol Customer Service.
15
M AGTROL
How to Select a Brake or Clutch
To properly size a brake or clutch, the operating parameters of MAXIMUM TORQUE (T), SLIP SPEED (RPM), and KINETIC
POWER (W) have to be determined. Once calculated, these parameters can be used to select the proper size brake or clutch from
the technical data provided on the product data sheets found in this catalog. These parameters are easily calculated from system
operating requirements such as: total web or strand tension (F); the radius of the full reel, roller, pulley, etc. (d/2); and linear
velocity/feed rate (v). The following example is given to show the relationship of these system requirements to the calculation
of the brake operating parameters. Since this example is not meant to cover all possible applications, an application data sheet
is provided on the following page. If additional assistance is needed, simply complete a copy of the data sheet and fax it to
Magtrol. Our Application Engineering staff will be pleased to assist you.
SAMPLE PROBLEM
Select a brake to tension a 7-inch diameter payoff reel in a system requiring total (web or strand) tension of 2 lb
and a process speed of 600 ft/min.
GIVEN:
FIND:
d
Diameter
=
7 in
T
Torque (lb·in)
F
Tension/Force
=
2.0 lb
RPM Slip Speed (rpm)
v
Linear Velocity
=
600 ft/min
W
Kinetic Power (watts)
Torque (T)
T
T
T
or T
=
=
=
=
Velocity/Feed Rate (v)
Force (lb) × Radius (in)
F × (d/2)
2 lb × 3.5 in = 7 lb·in
32 oz × 3.5 in = 112 oz·in
Total
Web/Strand
Tension (F)
Slip Speed (RPM)
RPM
RPM
RPM
RPM
RPM
=
=
=
=
=
Linear Velocity (in/min) / Circumference (in)
v × (π·d)
(600 ft/min × 12) / (π × 7 in)
7200 in/min / 21.98 in
327 rpm
Kinetic Power (W) see notes at box in right
W
W
W
W
=
=
=
=
SOLUTION:
NOTE:
16
hp × 746
(torque (lb·in) × speed (rpm) / 63025) × 746
(T × RPM / 63025) × 746
(7 lb·in × 327 rpm / 63025) × 746 = 27 watts
Full Roll
Diameter (d)
Hysteresis
Brake
NOTES
1 hp = 746 watts
Basic Horsepower Formula:
hp = torque (lb·in) × speed of rotation (rpm)
63025
From the Hysteresis Brake ratings on page 2, it can be seen that an HB-140 Hysteresis Brake
which has a rated torque of 140 oz·in, a maximum speed capability of 12,000 rpm, and a kinetic
power capability of 75 watts continuous, would be the proper selection for this application.
In a clutch application, slip speed is the difference in rotational speed between the input and output
members of the clutch assembly. If, in the above example, tensioning were being accomplished with
a clutch inserted between a take-up reel and a motor driving at 500 rpm, the actual slip speed used
to compute the kinetic power requirements would be 500 rpm (clutch input speed) - 327 rpm (clutch
output speed = 173 rpm). The difference in speed would obviously impact the result for kinetic power.
M AGTROL
Application Data Sheet
Company Information
Application Specifications
Company
Max. Torque Required
Address
Minimum Torque
Normal rpm
Intermittent rpm
Contact
Duty Cycle
Phone
Anticipated Qty
Fax
Target Price
E-mail
Electrical Specifications
Device Type
r
r
r
r
r
r
Hysteresis Brake
Matched Hysteresis Brake
Desired Volts, DC
Available DC Current
Electrical Time Constant
Large Bore Brake
Hysteresis Clutch
Ambient Conditions
Permanent Magnet Brake
Ambient Air Temperature
Permanent Magnet Clutch
Other Special Conditions
Application Description
Application Sketch
Complete the Application Data Sheet and fax, with an application sketch if necessary, to Magtrol, Inc. at (716) 668-8705.
17
M AGTROL
Special Designs and Modifications
Since 1953, Magtrol has created literally thousands of special and modified brake designs to help solve specific application
problems for our customers.
COMMON MODIFICATIONS
•
•
•
•
•
•
•
•
Non-Standard Coil Voltages
Special Shaft Configurations: keyways, flats, holes and
hollow
Dust Covers
Speed Pickups
Special Mounting Configurations
Non-Standard Lead: material, lengths, location
Higher Torque Devices
High Speed Units
FORCED AIR COOLED BRAKES
Compressed Air Cooled
HIGHER TORQUE CAPABILITY
It is Magtrol’s policy never to overstate the capabilities of
our products. As a result, our brakes are conservatively rated.
Higher torque values (15-25% above rated torque) are typically
available from each brake, depending on the brake being
ordered. In addition, special designs capable of producing
even higher torques are available.
Maximum Torque
+15 to +25%
TORQUE
Rated Torque
CURRENT
Blower Cooled
Unlike many other forms of braking devices, Magtrol
Hysteresis Brakes can be safely operated at relatively high
speeds, provided the combination of applied torque and speed
of operation do not cause the brake to be operated above its
kinetic power rating. The kinetic power rating of the brake
can be increased significantly, when necessary, by forced
air cooling. Magtrol has designed brakes with provisions
for forced air cooling utilizing compressed air supplied by
the machine builder and has also created special designs and
blower packages for use in high-torque/high-speed applications
where compressed air is not available.
METRIC HYSTERESIS BRAKES
Most of Magtrol’s Hysteresis Brakes and Matched Hysteresis Brakes are available in a metric design. For more details, please
refer to Magtrol’s Hysteresis Brake Metric Product Guide which can be accessed from our web site at http://www.magtrol.com/
brochures/metricbrake.pdf. Additional brake and clutch products that are currently available in standard English dimensions can
also be modified to meet metric requirements. Contact Magtrol or your local sales agent for more information.
Large Bore Brakes
For many years Magtrol has designed customized Hysteresis Brakes with large bores, and without
a shaft or bearings. These brakes are used for superior tension control for helical wrapping,
braiding and other feed through applications. Magtrol Large Bore Brakes are used in machines
for manufacturing cable, wire, fiber optic cable, rope and tape, among others. Magtrol Large Bore
Brakes provide smooth, repeatable torque, largely independent of speed. Maximum speeds up to
8000 rpm are available.
18
M AGTROL
Options and Accessories
BRAKE OPTIONS
POWER SUPPLIES
Base Mounting
For optimum torque stability, Magtrol offers four different
power supplies for its Hysteresis Brakes and Clutches:
Base mounting is standard on all HB-840 and HB-3500 brakes,
and is an available option on all other brakes.
Base Mount Ordering Information:
An HB-450 with a base mount is an HB-451 and an HB-1750
with a base mount is an HB-1751.
EE
ØKK (4)
Thru Holes
DD
JJ
BB
CC
AA
HH
GG
FF
All other dimensions per standard brakes
AA
BB
CC
DD
EE
FF
GG
HH
JJ
ØKK
*
0.201
HB-451
2.50 0.25 2.00 0.50 3.15 5.25 4.75 0.25
HB-840
4.13 0.25 3.63 0.50 3.15 5.25 4.75 0.25 1.81 0.204
HB-1751 4.00 0.50 3.00 0.50 4.75 9.00 8.00 0.50
*
0.406
HB-3500 5.00 0.50 4.00 0.50 4.75 8.50 7.50 0.50 3.73 0.406
* Contact Magtrol for drawing.
Torque Current Curves
Nominal performance characteristic curves similar to that
shown on page 16 will be provided by Magtrol, upon request.
Precise calibration curves for individual brakes can be
provided, but must be specified at time of order and do require
an additional charge. Contact Magtrol for price and delivery
of brakes complete with calibration curves.
Pillow Blocks
Pillow Block Assemblies are available for all brake and clutch
units except the HB-840 and HB-3500. Refer to each product’s
dimension page for pillow block drawings and dimensions.
Pillow
Block #
4702
4703
4705
4711
4714
4717
4720
4722
4736
4742
4744
4753
4755
4759
4760
19
Fits Brake/Clutch Model(s)
HB-8, HPM-8, HPMC-8, MHB-10.5
HB-16, HPM-16, HPMC-16
HB-32, HB-50, HPM-32, HPMC-32, MHB-38, MHB-50
HB-140, HPM-120, HPMC-120, MHB-140
HB-250, HPM-210, HPMC-210, MHB-250
HB-450, MHB-450
HB-750, MHB-750
HB-1750, MHB-1760
HB-2.5, HPM-2.5, HPMC-2.5, MHB-2.5
HCS-8
HCS-16
HCS-32
HCS-120
HCS-420
HCS-210
Model 6100 Closed Loop
SpeedControl/PowerSupply
The 6100 is a durable, variable,
closed loop speed control
power supply governed by an
adjustable proportional/integral
(PI) control algorithm for
unsurpassed stability in its class. Designed to work with a
Magtrol Hysteresis Brake that is specially fitted with a speed
pick-up, the 6100 functions as a power supply and also features
an easy-to-read digital speed display.
Model 5200 Power Supply
The Model 5200 is an unregulated 0 to 35 VDC Power Supply
which offers control and regulation of the braking torque via a
10 turn potentiometer. The 5200 is our most basic control for
manual testing in an open loop torque control mode.
Model 5210 Current Regulated Power Supply
The Model 5210 provides the same control capabilities as the
5200, and also provides current regulation of the brake. With
regulated current, the 5210 will eliminate torque drift caused
by temperature changes within the brake coil.
Model 5250 Current Regulated Power Supply
Model 5250-2 is an open frame, current regulated power supply.
COUPLINGS
Although intended for coupled service, moderate overhung
loads can be tolerated, depending on such operating
characteristics as speed, weight, and center of gravity of
load. Care should be taken to make certain that the shaft is
properly aligned. Couplings should be of proper size and
flexibility to adequately protect bearings from undue stress
and shock loading.
ORDERING INFORMATION
Specify the brake model number from the product ratings
table, followed by a -1, -2, or -3 signifying the required coil
voltage. For example, an HB-140 brake with a nominal 24
VDC coil would be ordered as an HB-140-2.
M AGTROL
OTHER MAGTROL PRODUCTS
Motor Testing Equipment
Magtrol offers three types of Dynamometers, each with a
different braking system to absorb load: hysteresis, Eddycurrent and powder. The dynamometers are complemented
by DSP-based controllers, power analyzers and LabVIEW™
based motor test software. Magtrol’s dynamometers,
electronics and software are used for testing all types of
electric and pneumatic motors, gas engines and gearheads, as
well as servo drives and inverters. With over 50 dynamometers
to choose from, and the availability of Customized Motor Test
Systems (CMTS), virtually every motor testing requirement can be met. Features include:
Torque from 0.02 N·m to 1200 N·m; Speed from 0 rpm to 70,000 rpm; Power from 7 W to
140 kW; DSP-based high speed controller with RS-232 and GPIB communication; Single and
three-phase power analyzers; LabVIEW™ based motor test software. Customized turnkey
systems with table/cabinet, power supply, PC, printer, fixtures, etc. available.
Load-Force-Weight Transducers
Highly reliable systems to measure and monitor load, force
and weight, commonly used to provide safety, control and
overload protection. Typical applications requiring LoadForce-Weight Systems include cranes, harbor installations,
oil drilling (on and off shore), hoists, winches and other heavy
lifting equipment. The systems are extremely accurate, can
be used for static or dynamic measurement, and are able
to withstand the most extreme environmental conditions.
Features include: Nominal value up to 2500 kN; Accuracy
class < 0.5%; Protection up to IP67; Transducer made of high resistance stainless steel;
Overload admissible 150%; Overload at rupture up to 500%; Test and certificate for component
to CE standards and material certificate on request; Analog or digital signal conditioner with
inputs up to 2 channels, 0–10 V, 4–20 mA outputs or bus interface, and digital display.
Displacement Transducers
Provides contactless measurement of absolute piston position
in hydraulic and pneumatic cylinders, and other applications.
Features include: Accuracy of 0.3%; Range from 50 mm to
1 m; High shock and vibration resistance; Ability to withstand
pressure up to 450 bar; Operating temperature of -40 °C
to +80 °C with active temperature compensation. High
temperature version up to 200 °C available.
Rotary Transmitters
Used for signal transmission of transducers on a rotating
part (e.g. engine shaft) to a stationary system (measuring
instrument or PC). Common applications include
thermocouples and strain gauges, as well as piezo electric
transducers to measure oscillation, acceleration, force and
pressure. The transmitter can also provide the supply signal
to each transducer. Features include: Noise 25 µV; 1, 4, 8 or
12 channels; Speed up to 40,000 rpm; Resistance < 0.2 mΩ;
Very low inertia; No slip-rings.
Due to the continual
development of our
products, we reserve
the right to modify
specifications without
forewarning.
ISO 9001
FIC A
01/05
WWW
TI
CER
TI
ON
SWISS
HB
Magtrol SA ISO 9001:2000 certified
For more information, contact your local sales agent:
For over 50 years, Magtrol
Inc and Magtrol SA have
been providing customers
with high quality products
to test, measure and control
torque-speed-power, loadforce-weight, tension and
displacement. Magtrol Inc,
which is headquartered
in the USA, is a leading
manufacturer of motor test
equipment and hysteresis
brakes and clutches. Magtrol
SA, located in Switzerland,
also offers motor test
equipment as well as products
to measure, control and
monitor load-force-weight
and displacement. Magtrol
offers customers a wide array
of measurement and control
solutions, combined with
excellent worldwide sales and
service.
MAGTROL INC
70 Gardenville Parkway
Buffalo, New York 14224 USA
Tel: +1 716 668 5555
Fax: +1 716 668 8705
E-mail: [email protected]
MAGTROL SA
Route de Moncor 4B
1701 Fribourg, Suisse
Tel: +41 (0)26 407 3000
Fax: +41 (0)26 407 3001
E-mail: [email protected]
Subsidiaries in:
France • Germany • U.K.
For worldwide network of sales
agents, visit our web site:
www.magtrol.com