Vicor Constant Current (CC) Demonstration Board - Manual (Page 7)

UG:007 vicorpower.com Applications Engineering: 800 927.9474 Page 7
Figure 6
PRM & VTM Under-voltage
Behavior
It is also possible to adjust (R10) clockwise fast enough before a PRM under-voltage event.
The PRM will aptly recover without registering an error. However, the VTM may have already
detected an under-voltage condition which will force it into shut down. Reset the VTM by
toggling the (SW01). The VTM requires a VC voltage if its input is lower than 26 V. An additional
circuit is required to provide a permanent solution in the special case where the PRM recovers
from a lower than 26 V. This circuit will detect a VTM fault and will force a PRM restart. Please
contact Vicor applications engineering for further details.
2.5 Measurement Precautions
The DC current limit protection uses a shunt resistor in the path of –IN and –OUT. Although
this is a non-isolated system, be advised that shorting –IN to –OUT disables this valuable
feature of the PRM. This warning extends to the use of multiple scope probes on the input
and output simultaneously.
Figure 7
PRM & VTM Under-voltage
Abnormal Behavior
VTM PC
PRM VC
VTM V OUT
PRM V OUT
VTM PC
PRM V OUT
PRM VC
VTM V OUT