User`s manual

28
Magtrol WB/PB DynamometersChapter 1 – Introduction
4
MAGTROL
pB DynaMoMeter ratings
Spec ifications
* Voltage at 20 °C is 30 volts.
The PB Powder Dynamometers contain, as their name
suggests, a magnetic powder. The electrical current passing
through the coil generates a magnetic field, which changes
the property of the powder, thus producing a smooth braking
100
1000
10
1
1
10
0.1
0.01
1 10 100 1000
3000 rpm480 rpm
10,000
Speed Limit for PB
Rotation Speed (rpm)
Torque (N·m)
Power (kW)
2 PB 115 (PO
WER)
1 PB 115 (POWER)
2 PB 115 (TORQUE)
1 PB 115 (TORQUE)
torque through friction between rotor and stator. The Powder
Dynamometers (PB) produce their rated torque at zero
speed. The element to be tested can be loaded at standstill to
determine the starting torque.
poWDer DynaMoMeter operating principLes
pB torque–speeD–poWer curves
The diagram below shows the characteristic curves for the 115 Series Powder Dynamometers.
Optical Speed Sensor
Each 115 Series PB Dynamometer has an optical speed sensor
with a 60-bit pulse wheel delivered as standard. For better
speed resolution in low speed applications, Magtrol offers a
600-bit or 6000-bit speed pickup (encoder) as an option.
Cooling Water Consumption
For all PB models: z 30 l/kWh at $t = 30 °C (Metric)
 z 8 gal/kWh at $t = 86 °F (US)
Model
Rated Torque
Drag Torque
De-energized
Nominal Input Inertia
Rated
Power
Rated
Speed
Max.
Speed
Excitation
Current*
N·m lb·ft N·m lb·in kg·m² lb·ft·s² kW rpm rpm A
1 PB 115
100 73.7 2 17.7 1.24 × 10
-2
9.14 × 10
-3
5 480 3000 2.5
2 PB 115
200 147.5 4 35.4 2.50 × 10
-2
1.84 × 10
-2
10 480 3000 5
PB 115