Parker PWD Series, Руководство по эксплуатации

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Electronic for proportional DC valves
Series PWDXXA-40X
Operation Manual
PWDXXA-40X_20 5715-677 UK.indd 26.01.17
Parker Hannifin Corporation
Hydraulics Group
Parker Hannifin Corporation
Hydraulics Group
Wiring diagram of enable input
Enable input
A signal voltage applied to the terminals 3 and
13 enables the solenoid output of the electronics.
Continuous operation of the electronics requires a
permanent voltage 5...30 V (i.e. the supply voltage).
In case of disabling the signal the solenoid output
of the electronics will be switched off in no time
independently from the command signal value. At
the same time the position controller output will be
clamped. In case of restarting the enable signal, the
valve spool takes its position always out of the fail
safe position. Preferable the enable signal should
be switched on together with the hydraulic pressure
supply. This forces the valve solenoid into drop out
condition when the hydraulic system is switched
off, and it avoids needless heating of the actuator.
The enable function represents no safety
arrangement against unwanted valve opera-
tion in terms of rules for accident prevention!
To block the valve function under all condi-
tions, more advanced steps are necessary,
i.e. the installation of additional safety check
valves.
Command signal input
The command signal to the valve will be connected
to the terminals 5 and 6 of the difference signal
input of the electronics. The connection has to be
performed shielded.
The stroke of the valve spool behaves proportional
to the command signal amplitude. Depending on
the selected electronic parameters different ver-
sions of command signal processing are available,
which are decribed below.
For the function description terminal 6 is assumed
as signal reference (0 V).
Details are shown from the technical specifi-
cations. The parameter options for the com-
mand signal input are described in the
chapter “Operating Instructions).
The command input signal needs to be fil-
tered as well as free of inductive surges and
modulations. To prevent malfunctions a high
signal quality is recommended.
Incorrect signal amplitude levels may disturb
the functionality and can damage the unit!