8
3.0 System Overview
3.2 Dynamometer
The dynamometer stand provides all of the connections from the sensors to the data acquisition system
and the mount for the power absorber.
SF-902S
The SF-902S system utilizes a floor-mounted absorber stand and a roll-around engine docking cart to
maximize test efficiency in high-volume environments. The versatile docking engine carts are used to
pre-stage and dress the engines before they are installed in the test cell. The dynamometer stays in the
test cell connected to all its supply lines and support systems. Roll the engine into the cell, dock the cart to
the dyno, and attach the fuel supply, airflow turbine, oil and coolant lines, and sensors. The cart is clamped
to the absorber stand for testing.
The boom provides clean routing of cables, fuel lines, and cooling pipes. It keeps all the accessories and
engine support lines close and available when needed.
The docking cart and boom system keep the test cell safe, organized, and attractive while allowing rapid
engine changes. Additional mounts for ignition boxes and work tools can be added if desired. Optional
features include cooling flow measurement, and temperature control on oil and engine coolant.
High-speed bearings are available for both the
SF-833 and SF-871 to increase the capability when
testing at extended intervals at speeds greater
than 12,000 rpm. The standard bearings can
handle speed up to 12,000 rpm as long as it is for
short durations. High-speed testing (>10,000 rpm)
shortens the life span of the bearings. The rate
of degradation is strongly linked with lubrication.
Fresh oil is better than older, contaminated oil.
Specifications
• Maximum absorber speed
– Standard bearings:
10,000 rpm
– High-speed bearings:
14,000 rpm
• Tachometer (magnetic pickup on 60-tooth gear)
– Range:
0–22,000 rpm
• Torque (Temperature-compensated strain gauge)
– Standard strain gauge:
0–1,000 lb-ft (0–1350 N-m) x 0.3 ± 0.2% fs
– High-torque strain gauge:
0–2,000 lb-ft (0–2,700 N-m) x 0.3 ± 0.2% fs
– Compensated temperature range:
0–150°F (–15° to 65°C)
Figure 3.3: SF Water Brake Absorber
Torque Capacity
