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Redundancy CPU

The redundancy CPUs have been designed specifically for Series 90-70 Hot Standby CPU

Redundancy applications.

Features

The Enhanced Hot Standby CPU supports floating point calculations, offers remote programmer keyswitch memory protection, and has seven status LEDs. Operation of the CPU may be controlled by the three-position RUN/STOP switch on the module, or remotely by an attached programmer. Program and configuration data can be locked through software passwords or manually by the memory protect keyswitch. When the key is in the protected position, a programmer connected to the Bus Transmitter Module can only change program and configuration data.

In a Hot Standby CPU Redundancy system, one CPU is configured as the Primary CPU and the other as the Secondary CPU. The Primary unit and the Secondary unit must each have a Redundancy CPU installed in slot 1 of rack 0.

 

 

Secondary Unit

 

 

 

 

 

Primary Unit

P C

B

R G

 

 

 

 

P C

B

R G

 

 

 

 

S P

T

C B

 

 

 

 

S P

T

C B

U

M M C

 

 

 

 

U

M M C

30

31

 

Redundancy Communications Link

CGR935

Redundancy Communications Link

or

 

CGR772

Genius Bus

in these slots

 

Not all features of other Series 90-70 CPUs are available in redundancy models. See chapter 4 for details.

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Series 90™-70 Enhanced Hot Standby CPU Redundancy User's Guide – May 2000

GFK-1527A

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Image 23
GE 90-70 manual Redundancy CPU, Features