Fluke 5790B, Руководство по обслуживанию

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5790B
Service Manual
2-6
System Interconnect Detailed Circuit Description
Digital Motherboard Assembly (A4)
The digital motherboard contains the soft-power circuit, line fuse, a fiber-optic
transmitter, and a fiber-optic receiver. It also contains connectors for the
transformer assembly (A22), CPU assembly (A20), front panel assembly (A2),
and the two 24 V dc fans mounted in the chassis.
The fiber-optic receiver and transmitter provide the serial communication link
between the CPU on the unguarded digital motherboard and the regulator/Guard
crossing on the guarded analog motherboard. This board also contains GPIB,
Ethernet, RS-232, and USB remote port connectors.
Transformer Assembly (A22)
The transformer assembly receives ac line inputs routed through the A4 digital
motherboard. This assembly supplies outputs throughout the Product, all of
which are routed through the A4 digital motherboard.
The transformer assembly, the filter assembly (A18), and the regulator portion of
the regulator/guard crossing assembly (A17) create the system power supply for
all analog assemblies.
Analog Motherboard Assembly (A3)
The analog motherboard contains the connectors for all assemblies in the
guarded section of the Product. The analog motherboard also contains five
relays, a fiber-optic transmitter, a fiber-optic receiver, and a cable for binding post
connections.
The fiber-optic transmitter and the fiber-optic receiver provide the serial
communication link between the regulator/guard crossing assembly and the CPU
assembly on the unguarded digital motherboard.
The cable from the motherboard to the binding posts consists of three insulated
wires and four shields.