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Installation and Maintenance Manual, Compact CA
Installation
3.1.7 Brake MDA
Functional description
MDA brake is of multi disc type with a rotating disc-centre (brake discs) and a stationary housing
(steel discs). It is a wet brake which means discs are running in oil-bath. The brake is actuated by
spring force and released by hydraulic pressure. Brake torque builds up in disc set between rotat-
ing disc-centre (brake discs) and stationary housing (steel discs) by a spring force acting on disc
set through a piston. The brake is normally activated giving brake torque. When pressurizing brake
the piston will move against cover and stop, giving zero brake torque. Intended use is as parking
brake! The brake can also serve as security brake and emergency brake.
Oils:
Conventional petroleum based hydraulic oils.
Be aware of high water content in oil, levels above 2% are not allowed due to use of water based
glue in disc set.
Minimum viscosity limit: 20 cSt
Torque levels in tech data is based on above mentioned oil.
Other type of oils can give different torques due to different friction coefficient (different additives
in oil).
3.1.8 Control of braking torque
The motor can be used for controlling the torque for the brake.
Start to drain the brake to tank, and increase pressure for the motor until it starts to rotate. Pres-
sure drop over the motor x T
s
for the motor gives braking torque for the brake.
If the motor can not rotate the brake, increase back pressure in the brake cylinder until the motor
can rotate the brake.
Braking torque = (Pressure drop over the motor x motor torque T
s
x 100)/( % Braking torque in dia-
gram 3.1 or 3.2. )With full torque and 10 rpm, the brake must not rotate more than max 10 seconds.
Summary of Contents for Compact CA
Page 1: ...Installation and Maintenance Manual Compact CA Motors ...
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Page 3: ...Installation and Maintenance Manual Compact CA EN411 18h 2011 ...
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