S&C Instruction Sheet 659-520
9
Components and Controls
Control Assembly
The control assembly inputs and indicators are located on the front of the control
assembly pull-out drawer located at the top-right side of the unit. See Figure 6. This
assembly contains all the necessary DSP, microcontroller, application, and scale boards
for operation. The inputs and indicators on the assembly are for service and mainte-
nance personnel use.
NOTICE
Access and use of the control assembly should be done by authorized personnel who
are trained in servicing the PCS .
Figure 6. Control assembly inputs and indicators.
Inverter
The inverter assembly consists of a three-phase, four-quadrant inverter that converts
the dc power to ac power. It creates the three-phase output from the dc battery bus.
Insulated-gate bipolar transistors (IGBTs) are used for switching, and pulse-width
modulation is used to control the real and reactive power produced and absorbed by
the PCS. See Figure 7.
Figure 7. Inverter assembly.
