© EPS Stromversorgung in 2022, this information is subject to change without notice
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30000800_manual_psb_10000_4u_30kw_en_04
3.4
Alarm conditions
This section only gives an overview about device alarms. What to do in case your device indicates an
alarm condition is described in section “3.7. Alarms and monitoring”.
As a basic principle, all alarm conditions are signaled optically (text + message in the display) and acoustically (if activated),
as well as status via digital interface. In addition, the alarms are reported as signals on the analog interface. For later acqui-
sition, an alarm counter can also be shown on display or read via digital interface.
3.4.1
Power Fail
Power Fail (PF) indicates an alarm condition which may have various causes:
•
AC input voltage too low (mains undervoltage, mains failure)
•
Defect in the input circuit (PFC)
•
One or multiple power stages in the device are faulty
As soon as a power fail occurs, the device will stop to supply or sink power and switch off the DC terminal. In case the power
fail was an undervoltage and is gone later on, the device can continue to work as before, but this depends on a parameter in
the settings menu called
DC terminal -> State after PF alarm
. The default setting would keep the DC terminal switched off,
but leave the alarm in the display for notification.
Powering the device down (power switch) can’t be distinguished from a supply blackout and thus the
device will signalize a PF alarm every time it’s switched off. This can be ignored.
3.4.2
Overtemperature
An overtemperature alarm can occur from an excess temperature inside the device and temporarily causes it to switch of
the power stage(s). This is usually due to the ambient temperature exceeding the specified operating temperature range of
the device. After cooling down, the device can automatically switch the DC terminal back on, depending on the setting of
parameter
DC Terminal -> State after OT alarm
. Also see section
3.5.3.1 for more information. The alarm will remain in the
display as notification and can be cleared anytime.
3.4.3
Overvoltage protection
An overvoltage alarm (OVP) will switch off the DC power stage and can occur if:
•
the device itself, when running in source mode, or an external source (in sink mode) brought a voltage to the DC terminal
higher than set for the overvoltage alarm threshold (OVP, 0...110% U
Nom
) or the connected load somehow returns voltage
higher than this threshold
•
the OVP threshold has been adjusted too close above the output voltage in source mode and if the device is in CC regulation
mode and then experiences a negative load step, it will make the voltage rise quickly, resulting in an voltage overshoot for
a short moment which can already trigger the OVP
This function serves to warn the user acoustically or optically that the device probably has generated or experienced an
excessive voltage which could damage the connected load application or the device.
•
The device is not fitted with protection from external overvoltage and could even be damaged
when not powered
• The changeover from operation modes CC -> CV in source mode can cause voltage overshoots
3.4.4
Overcurrent protection
An overcurrent alarm (OCP) will switch off the DC power stage and can occur if:
•
the current in the DC terminal reaches the adjusted OCP limit.
This function serves to protect the connected load application (source mode) or the external source (sink mode) so it’s not
overloaded and possibly damaged due to an excessive current.
3.4.5
Overpower protection
An overpower alarm (OPP) will switch off the DC terminal and can occur if:
•
the product of the voltage and current in the DC terminal reaches the adjusted OPP limit.
This function serves to protect the connected load application (source mode) or the external source (sink mode) so it’s not
overloaded and possibly damaged due to an excessive power.