Rockwell Automation SA3100 Power Module Interface (PMI) Regulator - Manual (Page 31)

PMI Regulator Motherboard 2-15
The system also warns of a DC bus undervoltage condition if the DC bus voltage
drops below the value of local tunable UVT_E0%. The system will set bit 1 in the Drive
Warning register (203/1203) if an undervoltage condition is detected.
A drive fault is generated (register 202/1202, bit 6) and the drive is shut down if the
DC bus voltage drops below the value stored in the Power Loss Fault Threshold local
tunable (PLT_E0%).
DC bus voltage ripple is monitored to detect an input phase loss in the rectifier section
of a three-phase AC input. However, this function can also be used with a common
bus supply. If the ripple exceeds the value stored in local tunable VRT_E0%, bit 3 will
be set in the Drive Warning register (register 203/1203).
The DC bus voltage is displayed in volts in UDC register 206/1206 (BUS_VDC%).
Bus voltage is measured across the bus capacitors and is resistively isolated before it
is sent to the power technology circuit.
2.2.3.6 Ground Current Feedback
The power technology circuit monitors the analog ground current feedback signal
through hardware and software to determine if the ground current is at a warning or a
fault level. The input signal is fed into a hardware comparator which will generate a
drive fault (register 202/1202, bit 2) and shut down the drive if the ground current
exceeds 20A for Power Modules A001/Q001 and A003/Q003, or 100A for all other
Power Modules.
The signal is also converted to a digital value and compared to the ground fault
warning threshold (GIT_E1%) local tunable. A drive warning is issued (register
203/1203, bit 2) if this threshold is reached.
Ground current feedback is displayed in amps in register 208/1208 (GI_FB%).
2.2.3.7 DESAT
The DESAT signal is used to indicate an overcurrent in one of the output power
devices (IGBTs). If an overcurrent is detected, the gate driver will shut off the IGBT to
prevent its destruction. Register 204, bit 6 (Inverter Power Device Fault) and register
202, bit 3 (Instantaneous Overcurrent Fault) will be set.
2.2.3.8 AC Line Feedback
The AC_LINE signal is used on drives larger than 30 HP to indicate the presence or
absence of the incoming AC line voltage.
Pin 28: GND_SHRT Ground current
Pin 29: DESAT
Pin 30: AC_LINE AC line voltage