Fisher FIELDVUE DVC6200f Instruction Manual page 193

Instruction Manual
D103412X012
D Cascade (Cas)—The block uses a set point supplied by another function block.
Note
The transducer block must be in Auto for the mode to go to AUTO, CAS or MAN.
D RemoteCascade (RCas)—The block uses a set point supplied by a host computer.
D Out of Service (OOS)—The block is not processed and the output is not transferred to I/O. The BLOCK_ERR [6]
attribute shows Out of service.
Mode Handling
Shed Options — RCAS Mode Only
Shed from or climb to a remote mode is determined by the parameter SHED_OPT [23]. A block climbs and sheds
through the same path. For example, if SHED_OPT [23] specifies that a block should shed to Auto, then, if the block
target mode is set to RCas, the block goes through Auto on the way to RCas. You can configure the shed option as
follows:
Shed With Return Options
Remote cascade connection failure shifts actual mode but keeps trying to restore remote cascade (in other words, the
remote cascade target mode stays in effect).
Normal—On failure of a remote cascade connection, the block attempts to attain the highest permitted non‐remote
mode until remote cascade is restored. Cas is the highest permitted non‐remote mode and Auto is is the next
permitted non‐remote mode. If Cas or Auto are not available, the block will shed by default to Man.
Retained Target—The retained target mode is the target mode for the block before changing the target mode to a
remote mode. On failure of a remote cascade connection, the block attempts to attain the retained target mode.
Auto—On failure of a remote cascade connection, the block attempts to attain Auto, if permitted, until remote
cascade is restored.
Man—On failure of a remote cascade connection, the block sheds to Man until a remote cascade connection is
restored.
Shed With No Return Options
For any shed with no return option, the target mode changes as determined by the option. Therefore, there is no
attempt to restore the connection following failure. The behavior on change to the remote cascade target mode is
identical to that for Shed With Return Options.
Normal—On failure of a remote cascade connection, the block sets the target mode to the highest permitted
non‐remote mode. Cas is the highest permitted non‐remote mode and Auto is is the next highest permitted
non‐remote mode. If Cas or Auto are not available, the block will shed by default to Man.
Retained Target—The retained target mode is the target mode for the block before changing the target mode to a
remote mode. On failure of a remote cascade connection, the block sets the target mode to the retained target mode.
Detailed Setup—DO Function Block
July 2013
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