National Instruments RMX-4120 User Manual page 142

RMX Programmable Power Supplies User Manual
The output voltage or output current fluctuates.
Are you using master-slave parallel operation? Compared to independent operation, the
performance degrades slightly during master-slave parallel operation.
Are the remote sensing cables and the sensing connectors connected? When you are not using
remote sensing, connect the sensing connectors in local sensing mode.
Are both the CV and CC LEDs turned on? If the output is oscillating when you are using remote
sensing, insert a capacitor across the load.
The circuit may be malfunctioning. Immediately stop using the RMX programmable power
supply, and have it repaired.
Do the sensing cables or load cables have poor contact, or are the cables broken? Turn the
POWER switch off, and check the wiring.
Does the load current have peaks, or is it pulse shaped? The peak values may be exceeding the
set constant current. Increase the set constant current or increase the current capacity.
The output voltage is offset from the voltage that the RMX programmable power supply
was generating when it was turned on.
Has 30 minutes passed since the power was turned on? Warm up the RMX programmable power
supply for at least 30 minutes.
Is the bleeder circuit set to oFF?
Is the bleeder circuit set to oFF? If the bleeder circuit is set to oFF, the voltage that was present
when the output was on will remain. Set the bleeder circuit to on.
Output Ripple is Large
The ripple sometimes becomes large.
Is the input voltage outside the range? Apply a voltage that is within the input voltage range.
The ripple increased when the RMX programmable power supply was installed in a
different location.
Is something nearby generating a strong magnetic or electrical field? Take measures such as
moving the RMX programmable power supply away from the field sources or twisting the
cables connected to the RMX programmable power supply.
The output ripple is large during external control.
Is there a large amount of external voltage noise? Take measures against noise.
The ripple increased when the load cable was changed.
Are the remote sensing cables connected? When you are not using remote sensing, disconnect
the remote sensing cables.
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