Elektro-Automatik PSI 9000 DT Series, Operating Manual

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EA Elektro-Automatik GmbH
Helmholtzstr. 31-37 • 41747 Viersen
Germany
Fon: +49 2162 / 3785-0
Fax: +49 2162 / 16230
www.elektroautomatik.de
ea1974@elektroautomatik.de
PSI 9000 DT Series
3.3 Alarm conditions
This section only gives an overview about device alarms. What to do in case your device indi-
cates an alarm condition is described in section „3.6. Alarms and monitoring“.
As a basic principle, all alarm conditions are signalled optically (text + message in the display), acoustically (if
activated) and as a readable status via the analog and digital interfaces. For later acquisition of the number of
occurred alarms, an alarm counter can be read from the display or via digital interface.
3.3.1 Power Fail
Power Fail (PF) indicates an alarm condition which may have various causes:
•
AC input voltage too low
• Defect in the input circuit (PFC) or internal auxiliary supply
In case the PF alarm has been caused by AC supply undervoltage, the device will only temporarily stop supplying
power and can continue automatically once the undervoltage has gone, depending on the setting of parameter
“DC output after PF alarm” (see
„3.4.3. Configuration via MENU“
).
Switching off the device by the mains switch can’t be distinguished from a supply blackout and
thus the device will signalise a PF alarm every time the device is switched off. In this situation
the alarm must be ignored.
3.3.2 Overtemperature
An overtemperature alarm (OT) will cause the device to switch off the power stages and can occur if
•
the internal temperature of the device exceeds a specific level (overheating).
This would be the case if the ambient temperature also exceeds the rated operation temperature limit or when the
device fan has failed. After cooling down, the device can automatically switch the power stage back on, depending
on the setting of parameter “DC output after OT alarm”. See section
„3.4.3.1. Menu “General Settings”“.
3.3.3 Overvoltage protection
An overvoltage alarm (OVP) will cause the device to switch off the DC output and can occur if
• the power supply itself, as a voltage source, generates an output voltage higher than set for the overvoltage
alarm threshold (OVP, 0...110% U
Nom
) or the connected load somehow returns voltage higher than set for the
overvoltage alarm limit.
• the OV threshold has been adjusted too close to the output voltage. If the device is in CC mode and if it then does
a negative load step, it will cause the voltage to rise very quick, possibly resulting in a short voltage overshoot
which could already trigger the OVP.
This function serves to warn the power supply user acoustically or optically that the device has probably generated
an excessive voltage which could damage the connected load.
• The device isn’t fitted with protection from external overvoltage
• The changeover from operation mode CC -> CV can generate voltage overshoots
3.3.4 Overcurrent protection
An overcurrent alarm (OCP) will cause the device to switch off the DC output and can occur if
• the output current in the DC output exceeds the adjusted OCP limit.
This function serves to protect the connected load application so that this isn’t overloaded and possibly damaged
due to an excessive current.
3.3.5 Overpower protection
An overpower alarm (OPP) will cause the device to switch off the DC output and can occur if
•
the product of the output voltage and output current in the DC output exceeds the adjusted OPP limit.
This function serves to protect the connected load application so that this isn’t overloaded and possibly damaged
due to an excessive power consumption.