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EPS Stromversorgung GmbH
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Germany
Fon: +49 821 / 570451-0
Fax: +49 821 / 570451-25
PSI 9000 3U Series
3.5.4.5
Simplified diagram of the pins
+
Digital Input (DI)
It requires to use a switch with low resist
-
ance (relay, switch, circuit breaker etc.) in
order to send a clean signal to the DGND.
A digital output from a circuit or PLC may
not be sufficient if not an “open collector”.
V~0.5
AGND
Analog Input (AI)
High resistance input (impedance
>40 k....100 kΩ) for an OA circuit.
4.
7k
12V
+10V
Digital Output (DO)
A quasi open collector, realised as high
resistance pull-up against the internal sup-
ply. In condition LOW it can carry no load,
merely switch, as shown in the diagram
with a relay as example.
V~2
AGND
Analog Output (AO)
Output from an OA circuit, only mini
-
mally impedant. See specifications
table above.
3.5.4.6 Application examples
a) Switching the DC output with pin “REM-SB”
A digital output, e.g. from a PLC, may be unable to cleanly pull down the pin as
it may not be of low enough resistance. Check the specification of the controlling
application. Also see pin diagrams above.
In remote control, pin REM-SB is be used to switch the DC output of the device on and off. From
KE firmware version 2.07, this is also available without remote control being active.
It is recommended that a low resistance contact such as a switch, relay or transistor is used to
switch the pin to ground (DGND).
Following situations can occur:
• Remote control has been activated
During remote control via analog interface, only pin “REM-SB” determines the states of the DC output, according
to the levels definitions in
. The logical function and the default levels can be inverted by a parameter in the
setup menu of the device. See
If the pin is unconnected or the connected contact is open, the pin will be HIGH. With parameter
“Analog interface REM-SB” being set to “normal”, it requests “DC output on”. So when activating
remote control, the DC output will instantly switch on.
• Remote control is not active
In this mode of operation pin “REM-SB” can serve as lock, preventing the DC output from being switched on by
any means. This results in following possible situations:
DC-
output
+
Pin
„REM-SB“
+
Parameter
„Rem-SB“
Behaviour
is off
+
HIGH
+
normal
DC output not locked. It can be switched on by pushbutton “On/Off”
(front panel) or via command from digital interface.
LOW
+
inverted
+
HIGH
+
inverted
DC output locked. It can’t be switched on by pushbutton “On/Off”
(front panel) or via command from digital interface. When trying to
switch on, a popup in the display resp. an error message will be
generated.
LOW
+
normal