Theory of Operation

Theory of Operation

This Chapter provides a brief overview of the theory of operation for the VX1410A & VX1420A IntelliFrame Mainframe. Figure 6±1 shows the functional block diagram of the mainframe and the major components.

IntelliFrame Mainframe The standard mainframe contains the following major components:

HPower supply

HBackplane

HEnhanced Monitor board

HTemperature Sense board

Power Supply. The power supply provides all voltages and currents to the mainframe. The power supply connects to the backplane at P25, P26, P27, and P28 through the Power Supply. The power supply can be replaced as a single unit.

Backplane. The Backplane (A4) provides all the connections to module slots 0 through 12 in the mainframe. It also has connections to all other circuit boards and modules in the mainframe.

The front panel On/Standby DC switch connects to one of two connectors at the top of the backplane. When the switch is connected to J22, the switch controls the power in the mainframe. When the switch is connected to J23, the power-on functions are controlled by an external source through the 25-pin connector on the Monitor board. Although the switch still illuminates when power is applied to the mainframe, the on/off function of the switch is disabled. (Refer to Remote Power Switch Configuration on page B±1 for information on powering the mainframe with a remote momentary switch.)

The backplane connects to the Power Supply at J25 to J28. A 30-wide ribbon cable at 0J4 on the backplane connects to J16 on the Temperature Sense board. Connectors 0J1, 0J2, and 0P3 carry instrument monitoring information from the backplane to the Monitor board.

VX1410A & VX1420A IntelliFrame Mainframe Instruction Manual

6±1