User manual

GMC-I Messtechnik GmbH 17
☞ During auto-sensing: Sensing lead polarity is reversed, or an
output lead is/was interrupted or was not taken into
consideration when adjusting OVSET, so that the voltage at
the output terminals which is relevant for the OVP function is
increased by the amount to be compensated for at both leads,
and is higher than USET voltage as controlled by the
sensors at the load side (too little difference between
selected USET and OVSET values).
☞ Parallel connected voltage sources
Green CC LED OCP (overcurrent protection)
Overcurrent protection is active.
If the OCP ON function has been activated,
the output was operated for a duration of
t > DELAY in the current limiting mode
(current regulation). The output has been
deactivated.
Possible causes:
☞ Current setpoint ISET has been set too low manually, memory
recall, programming error or Iset control signal to the
analog interface
☞ Current transients caused by switching inductive
consumers (DELAY time may be set too low)
Yellow Pmax LED OTP (overtemperature protection)
Electronic power limiting has been
triggered
(overload! Pout > Pnom).
Possible causes:
☞ Impaired cooling, e.g. air inlet or exhaust vents are
obstructed.
☞ Excessive ambient temperature
The KONSTANTER is capable of continuously supplying
nominal power at ambient temperatures of up to 50 °C
(measured at the air inlet vents). Approximately 120 to
130% nominal power can be drawn intermittently
(triggering point for electronic power limiting). Continuous
operation at these levels may cause triggering of the
overtemperature protection function.
☞ The fan has failed.
☞ A device error or defect has occurred.
After the cause of triggering has been eliminated, the output can be
reactivated.
[4] Output
Selected constant voltage or constant current is available from
the safety jacks at the front panel.
 blue Negative output pole
 red Positive output pole
yellow-green Earth connection point for the output or
shield terminal if shielded output leads are
used. The ground terminal is connected to
the housing and the earthing contact at the
mains connection.
The power consumer can also be connected to the OUTPUT
interface [22] at the rear panel.
[5] Left-Hand Display with [7]
[6] Display Parameter Indicators (LEDs)
As a default setting, the measured output voltage value Uout
appears in volts at the left-hand display.
The display can be switched to the momentary measured voltage
value Uset by slightly turning the voltage adjusting knob [5], or by
pressing the <ENTER> key.
The LEDs allocated to the display indicate which value is being
displayed (green LED = measured value, yellow LED = setting
value).
 Uout / V (gr) = Measured output voltage value in V
 Uset / V (ye) = Output voltage setpoint in V (blinking
indicates that the displayed value has not
yet been set)
If no adjustment is made for a period of 10 seconds during the
display of a setting value, the display returns to Uout
automatically.
Additional KONSTANTER functions can be selected with the
<SELECT>, <FUNCTION>, <RCL> and <SAVE> keys. The function
code or the parameter name appears at the left-hand display
in this case.
[7] Rotary Knob for Voltage Adjustment <Uset>
Voltage is adjusted in the usual fashion with the rotary knob.
However, the adjusting element is not a potentiometer, but
rather a rotary pulse encoder which generates 24 pulses per
revolution, whose setting resolution (step size per pulse) can
be set to either coarse, medium or fine with the <SELECT>
function. This allows for convenient, precise adjustment on the
one hand, and also assures that no change occurs to the
selected value when switching between remote control and
manual operation.
When the voltage adjusting knob is turned, the left display is
first switched to the Uset display and the current voltage
setpoint appears. After approximately 0.4 seconds, one of the
decimal places starts blinking at the display in order to indicate
selected adjusting sensitivity. From this point on, turning the
rotary knob changes the display value, and thus the setpoint
value, at the selected decimal place.
Clockwise rotation increases the value, and counterclockwise
rotation decreases the value.
If no adjustment is made for a period of 10 seconds, the
display automatically returns to the measured voltage value
Uout. The display can be immediately switched to the Uout
value by pressing the <CE/LOCAL> key.
☞ Detailed explanations are included in chapter 4.6.
[8] Right-Hand Display with [10]
[9] Display Parameter Indicators (LEDs)
As a default setting, the measured output current value Iout
appears in amperes at the right-hand display.
The display can be switched to the momentary current setpoint
Iset by slightly turning the current adjusting knob [8], or by
pressing the <ENTER> key twice.
The LEDs allocated to the display indicate which values are
being displayed (green LED = measured value, yellow LED =
setting value).
 Iout/A (gr) = Measured current value in A
 Iset / A (ye) = Current setpoint in A (blinking indicates that
the displayed value has not yet been set)
If no adjustment is made for a period of 10 seconds during the
display of a setting value, the display returns to Iout
automatically.