Selection, Installation Location, And Installation Direction Of The Pressure Transducer - Bosch REXROTH A4 Series Instruction Manual

58/104 Installation
Selection of the pressure
transducers
Bosch Rexroth AG, A4... with HS5E pilot control valve/Series 3x, RE 92076-01-B/10.2017
Recommendation:
On the system-side, the voltage supply of the HS5E pilot control valve should be
fuse-protected using a 4 A slow-blow fuse
The pilot valve does not have an enable input to block the function of the valve.
In the event of a fault, the drive enable should be canceled via fieldbus. All other
safety-relevant intervention must be carried out by the higher-level control (e.g.
drive motor OFF, close isolator valves, etc.)
7.6.7 Selection, installation location, and installation direction of the pressure
transducer
To reduce the number of variants, only the 630 bar pressure stage of the HS5E
control systems is listed. If necessary, it is also possible to combine other pressure
stages (under selection of the appropriate electrical interface!) It is, however, only
possible to deal with orders for pressure transducers of this type separately from the
HS5E control system.
A differentiation is made on a signal-specific basis between
• sensors with a current interface, and
• sensors with a voltage interface.
Here, the usual signal limits are between 0...20 mA or 0...10 V.
Within these limits, there are further modifications that depend, for example, on
whether cable breaks are to be monitored too.
From a technical point of view, the efficiency of the pressure transducer must be
matched to the HS5E system to make it possible to achieve optimum results for
accuracy, dynamics, and reproducibility.
The pressure transducers that we recommend are listed in the RE sheets of the
respective HS5E system.
• Our pressure transducer model "HM20-2X" (HS5EP) with (4...20 mA) current
interface has a two-wire connection and makes it possible to transfer signals on
a noise-immune basis across relatively long distances (depending on the cable and
the permissible ohmic resistance of the pressure transducer)
Looping in of further pick-ups is possible taking into account the respective input
resistances.
• Our pressure transducer model "HM20-2X" with (0...10 V) voltage interface has
a three-wire connection and a built-in DC/DC converter that effectively rules out
disturbances to the analog signal that are caused by the voltage supply.
You should avoid transferring the signal across long distances.
The benefit of the pressure transducer is that you easily check the signals using
a voltmeter without needing to interfere with the connection lines.