Agilent Technologies 5071A manual A11 Power Steering Logic Assembly

Assembly-Level Service

Theory of Operation

A11 Power Steering Logic Assembly

Option 048: The paragraph that describes the power-steering logic circuit on page 3-

25 is changed:

A11 directs the outputs of two power sources to the main instrument input bus in a hierarchical order. The two power sources are: 1) the external dc input and 2) the dc from the ac line (through a transformer, rectifier, and filter). The main instrument power input goes directly to A12 Dc-Dc Power Converter Module which supplies power to all instrument components (except A11 Power Steering Logic Assembly itself, which has its own supply). All circuits are divided up into three functional blocks: external dc, housekeeping, and dc from ac line.

Figure 3-3. A1 Power Supply/Distribution Schematic Diagram

Option 048: The circuit diagram on page 3-26 is changed:

•The input voltage range for the External DC Input Filter Block is 40-58 VDC,

•The value of C2 is 470 ∝ f,

•The value of C4 is 4700 ∝ f ,

•The value of R4 is 17.8 Ω ,

•The voltage rating of VR1 is 68V,

•The value of L1 is 235 ∝ H.

Figure 3-3. A1 Power Supply/Distribution Schematic Diagram (cont.)

Option 048: The circuit diagram on page 3-27 is changed:

•The value of C3 is 470 ∝ f,

•The value of R7 is 31.6 kΩ .

•The value of R8 is 31.6 kΩ .

Figure 3-4. A1 Slot/Module Interconnect Diagram

Option 048: The slot/module interconnect diagram on -page3-28 is changed.

The Ext DC Connector (J1) is deleted and replaced by a five-screw terminal strip and associated subpanel assembly ( part number 05071-60277) that includes the dc input fuse.

Refer to Figure 2-1 for a schematic diagram of the five-screw dc input terminal strip and associated power steering diodes for dc power input 1 and input 2.

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