User manual

Page 44
EL 9000 T Series
www.elektroautomatik.de
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EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
3.6 Alarms and monitoring
3.6.1 Denition of terms
There is a clear distinction between equipment alarms (see „3.3. Alarm conditions“) such as overvoltage or over-
heating,anduserdenedeventssuchase.gOVD overvoltage monitoring.Whilst device alarms primarily serve
toprotectthesourcebyswitchingofftheDCinput,userdenedeventscanalsoswitchofftheDCinput(Action=
ALARM),butcanalsosimplymaketheuserawarebyapop-upinthedisplay.Theactionsdrivenbyuserdened
events can be selected:
Action Impact Example
NONE Userdenedeventisdisabled.
SIGNAL
On reaching the condition which triggers the event, the action SIGNAL will
show a text message in the status area of the display.
WARNING
On reaching the condition which triggers the event, the action WARNING
will show a text message in the status area of the display and pop up an
additional warning message.
ALARM
On reaching the condition which triggers the event, the action ALARM will
show a text message in the status area of the display with an additional
alarm pop-up. Furthermore the DC input is switched off. Certain device
alarms are also signalled to the analog interface or can be queried via the
digital interface.
3.6.2 Device alarm and event handling
Important to know:
• The current drained from a switching power supply or similar sources can be much higher than
expected due to capacities on the source’s output, even if the source is current limited, and
might thus trigger the overcurrent shutdown OCP or the overcurrent event OCD of the electronic
load, in case these supervision thresholds are adjusted to too sensitive levels
• When switching off the DC input of the electronic load while a current limited source still sup-
plies energy, the output voltage of the source will rise immediately and due to response and
settling times in effect, the output voltage can have an overshoot of unknown level which might
trigger the overvoltage shutdown OVP or overvoltage supervision event OVD, in case these
thresholds are adjusted to too sensitive levels
A device alarm incident will usually lead to DC input switch-off, the appearance of a pop-up in the middle of the
display to make the user aware. The alarm must always be acknowledged. If the alarm condition no longer exists,
e.g. the device has cooled down following overheating, the alarm indication will disappear. If the condition persists,
the display remains and, following elimination of the cause, must be acknowledged again.
► How to acknowledge an alarm in the display (during manual control)
1. If the alarm is indicated as a pop-up, tap OK.
2. If the alarm has already been acknowledged, but is still displayed in the status area,
thenrsttapthestatusareatomakethealertpopupagainandthenacknowledge
with OK.
In order to acknowledge an alarm during analog remote control, see „3.5.4.3. Acknowledging device alarms“. To
acknowledge in digital remote, refer to the external documentation “Programming ModBus & SCPI”.