Noise Development In The Unit; Pulsation Damper; Master/Slave Operation - Bosch REXROTH A4 Series Instruction Manual

30/104 About this product
Bosch Rexroth AG, A4... with HS5E pilot control valve/Series 3x, RE 92076-01-B/10.2017

5.6.1 noise development in the unit

"Noise" consists of various components. The "noise" overall result is not just
affected by airborne noise but also by structure-borne and fluid noise.
Due to unfavorable installation and piping conditions, the sound pressure level of
the overall system can be 5 to 10 dB(A) higher than the pump's individual value.
Measures for reducing noise include, for example:
• Low-noise containers
• A damping ring between the pump and the pump carrier
• Elastic pipe feedthrough
• Damping rails below the motor
• Installing the pump at an adequate distance from the container wall

5.6.2 Pulsation damper

With some special applications, we recommend using a pulsation damper for
operation. Due to the reduction in the pressure pulsation that is typical of pumps,
this also positively affects the noise level of the hydraulic system.
You can find information about this in data sheet RE 50142.
5.7

Master/slave operation

p, Q
p
U(i)
(α )
actual
MASTER
Pressure
Swivel
angle
Setpoint
value
Fig. 5: Hydraulic coupling of HS5E control systems
In theory, you can hydraulically couple any HS5E control systems you like to achieve
higher displacements.
When doing this, you only need to specify one master pump to which the pressure
transducer is connected.
Now, the master regulates both the pressure and the swivel angle according to
the external command value specifications and passes on its internal swivel angle
command value to the slave pumps as the swivel angle command value. This
guarantees even and synchronous swiveling.
(α )
set
Slave
1
(α )
set
Slave
n