metso automation PDP 400 maxDPU4F Series, Руководство по оборудованию

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Chapter 7
Starting the DPU
Startup States
Refer to this chapter to learn how to:
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Start a standalone DPU
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Start DPUs in a backup pair
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Replace a DPU in a backup pair
When a DPU is first powered, it checks for a valid configuration and
database existing in its flash memory and proceeds to load it. The DPU then
listens over the backup link to see if another DPU is active and in control
before it operates on the loaded configuration.
If no backup DPU is present (no backup link communications, no Network
A/B communications, no active pulses on the backup link cable) then, the
DPU continues to operate with its loaded configuration and intended
operation as either a standalone DPU or a backup DPU. It becomes the
Active DPU since no other DPU is in control.
If a backup DPU is present then, this DPU listens to the other DPU over the
backup link as to its current operation as Standalone or Redundant DPU. If
the other active DPU is set as a Redundant DPU (NOT Standalone) then, this
inactive DPU will erase its configuration/database and proceed to gather
configuration and database information over the backup link. This DPU will
move from an empty state to a warming state and then to a hot standby state
and becomes ready to assume control when commanded to take over.
Demanding a Blank Startup
When a DPU is first placed in service it is advisable to clear any previous
configuration data that may remain in its flash memory. To do this, before
applying power to the DPU, set the Mode switch to ‘B’ on the DPU. After
the DPU has gone through its startup sequence as described in "Starting a
Standalone DPU," be sure to set the Mode switch back to ‘F’ to prevent
future Cold startups.