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SYDFED-2X, SYDFED-3X, SYHDFED-1X
| Installation
Bosch Rexroth AG, Edition 11.2021, RE 30017-B
Recommendation:
The voltage supply for the VT-DFPD pilot valve should be protected with a 4 A/
slow-blowing fuse on the system side.
The pilot valve is not provided with an enable input to block the function of the
valve.
In the event of an error, the controller enable should be withdrawn via field
bus. All further, safety-relevant interventions must be made by the higher-level
control (e.g. switching the drive motor OFF, closing the shut-off valves, ....).
7.6.8 Selection, place of installation and mounting orientation of the pressure
transducer
To reduce the number of variants, only pressure rating “315 bar” is given in the
ordering code of the SY(H)DFED control systems. If required, other pressure
ratings can be combined (with the correct selection of the relevant electrical
interface!). Such pressure transducers must, however, be ordered separately for
the SY(H)DFED control system.
In terms of signals, the sensors have to be distinguished as follows:
• Sensors with current interface and
• Sensors with voltage interface
Here, the usual signal limits are between 0...20 mA or 0...10 V, respectively.
Within these limits, there are further modifications that depend on further options,
such as monitoring for cable break.
From a technical point of view, the efficiency of the pressure transducer must be
adapted to the SY(H)DFED system in order that the best possible results can be
obtained with regard to accuracy, dynamics and repeatability.
The pressure transducers recommended by us are listed in the RE data sheets of
the relevant SY(H)DFED system.
• Our pressure transducer model “HM20-2X“ with current interface (4...20 mA)
is provided with a 2-conductor connection and allows the fail-safe transmission
of signals – even over greater distances (depending on the cable used and the
permitted load of the pressure transducer).
Further pick-offs can be looped in taking into account the relevant input
resistances.
• Our pressure transducer model “HM20-2X“ with voltage interface (0...10 V) has
a 3-conductor connection and an integrated DC/DC converter, which effectively
rules out disturbances on the analog signal caused by the voltage supply.
The transmission of the signal over longer distances should be avoided.
The advantage of the pressure transducer lies in the simple checking of
the signals by measurement using a voltmeter without intervention into the
connection cables.
• The “HM20-2X/...F-C13” pressure transducer has a voltage interface (0.5...5 V)
with a ready-to-connect, standardized connection cable for direct connection to
X2M1 or X2M2.
CAUTION
! Uncontrolled increase in pressure!
Risk of injury!
▶ The pressure transducer must be wired so that it cannot be short-circuited,
because in the event of a missing pressure signal, the control electronics
can no longer detect the pressure, which causes an uncontrolled increase in
pressure.
Observe the operating instructions of the pressure transducer HM20, RE 30272-B.
Selection of the pressure
transducers
