Amb Function Block - Honeywell UMC800 Reference Manual

2.7 AMB Function Block

Description
The AMB label stands for Auto/Manual Bias Function. This block is part of the Loops category. It looks
like this graphically on the Control Builder.
Function
On transfer from Manual to Auto; Bias is calculated to make PV + Bias = Output.
Inputs
PV1 = Process Variable Input (%)
TRV = Output Track Value in percentage ( Output = TRV Value when TRC is ON).
TRC = Output Track Command—1 = enable TRV(Mode = Local Override), 0 = disable
MDRQI= External Mode Request (connected to the MDRQO output of a MDSW function block) encoded
as follows:
0.0 = No Change
1.0 = Manual Mode Request
2.0 = Automatic Mode Request
Outputs
OUT = Control Output (-5 to 105%)
AL1 = Alarm 1
AL2 = Alarm 2
MODE = Actual Mode encoded as follows: (Connect to Mode Flags block [MDFL] to encode mode
status.)
4.0 LSP AUTO
5.0 LSP MAN
7.0 LSP LO (Local Override)
Block Properties
Double click on the function block to access the function block properties dialog box.
Configuration Parameters
The Auto/Manual Bias properties dialog box is divided into three tab cards
GENERAL
RANGE/LIMIT
ALARMS
Click on the tab to access the properties for that tab.
3/99 Function Block Reference Guide
Function Blocks
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