Instruction Manual
DVC6200f Digital Valve Controller November 2011
D103412X012
Note A downstream block changing to Out of Service impacts the mode of the upstream block. Refer to the block hierarchy in figure D‐2.
Figure D‐2. Digital Valve Controller Block Hierarchy Example
RESOURCE BLOCK
PID BLOCK
ANALOG OUTPUT (AO) BLOCK
TRANSDUCER BLOCK
NOTES: 1. CHANGING THE RESOURCE BLOCK TO OUT OF SERVICE CHANGES ALL FUNCTION BLOCKS TO OUT OF SERVICE, BUT DOES NOT AFFECT THE TRANSDUCER BLOCK. 2. CHANGING A DOWNSTREAM BLOCK TO OUT OF SERVICE AFFECTS THE UP STREAM BLOCK. FOR EXAMPLE: WHEN THE TRANSDUCER BLOCK IS OUT OF SERVICE, THE AO BLOCK MODE WILL CHANGE TO IMAN (INITIALIZE MANUAL).
Note There is no mode associated with the FOUNDATION fieldbus Loop. Mode is dependent on the blocks within the Loop.
Explanation of Modes Out of Service (OOS)—The functions performed by the block are not executed. If the block has any outputs, these typically do not update and the status of any values passed to downstream blocks will be “BAD”. To make changes to some of the parameters in a block requires that the block be Out of Service. Initialization Manual (IMan)—Only the AO, DO, OS and PID blocks support this mode. When one of these blocks detects a loss of a correct path to the downstream block (such as when the downstream block is in the OOS, Man, or LO mode), it enters the IMan mode. For example, when the transducer block enters the OOS mode, the AO block enters the IMan mode. Local Override (LO)—Only the AO, DO, and PID blocks support this mode. If the PID block enters the LO mode, the block output follows the tracking value (TRK_VAL), if external tracking is enabled by TRK_IN_D. In the AO and DO block, the block enters LO mode when the block detects that fault state is active. In this case, the output is determined by the selection for I/O_OPTS. Manual (Man)—If the data status of a function block's input is bad or its target mode is Man, the block enters the manual mode. In this mode, the function block does not update its OUT value. If the target is Man, the user may write a desired value to the output. Automatic (Auto)—The block performs the specified calculations based on the local set point and outputs the result, independently without interfacing with another block. The user can write to the set point of a block in this mode. Any block outputs continue to update. Cascade (Cas)—The block performs the specified calculations based on the set point from another block via the cascade input parameter and outputs the result. Any block outputs continue to update.
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