The compact option of HVM sistem is designed to supply of test and small size experimental setup.
The base module of sistem is Master Unit uncluded LV and HV source to supply up
to 8 of 16 channels HV distribution modules.
PCI HVM Host card is used to drive Master and Distribution modules.
The positive and negative HVM options are possible.
For more detail review see:
System CMS/LHCb HV for LHCb experiment