User manual

Page 44
EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
[e-mail]
PS 3000 C Series
• 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o
+
HIGH
+
normal

DCoutputnotlocked.Itcanbeswitchedonbypushbutton“On/O”
(front panel) or via command from digital interface.
LOW
+
inverted
+
HIGH
+
inverted

DCoutputlocked.Itcannotbeswitchedonbypushbutton“On/O”
(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
IncasetheDCoutputisalreadyswitchedon,togglingthepinwillswitchtheDCoutputo,similartowhatitdoes
in analog remote control:
DC-
output

Pin
„REM-SB“
+
Parameter
„REM-SB“

Behaviour
is on

HIGH
+
normal

DC output remains on, nothing is locked. It can be switched on or
obypushbuttonordigitalcommand.
LOW
+
inverted

HIGH
+
inverted

DCoutputwillbeswitchedoandlocked.Lateritcanbeswitched
on again by toggling the pin. During lock, pushbutton or digital com-
mand can delete the request to switch on by pin.
LOW
+
normal
b) Remote control of current and power.
Requires remote control to be activated (Pin “Remote” = LOW)
The set values PSEL and CSEL are generated from, for ex-
ample, the reference voltage VREF, using potentiometers for
each. Hence the electronic load can selectively work in current
limitingorpowerlimitingmode.Accordingtothespecication
of max. 5 mA for the VREF output, potentiometers of at least
10kΩmustbeused.
The voltage set value VSEL is directly connected to AGND
(ground)andthereforehasnoinuenceonconstantcurrentor
power operation.
If the control voltage is fed in from an external source it is nec-
essary to consider the input voltage ranges for set values (0...5
V or 0...10 V).
Use of the input voltage range 0...5 V for 0...100% set value halves the eective resolution.
Example with
external voltage
source
Example with
potentiometers
c) Reading actual values
The AI provides the DC output values as current and voltage monitor. These can be
read using a standard multimeter or similar.