Honeywell UDC 3300 manual What happens when you change modes, Changing Operating Modes Mode Change

What happens when you change modes

Table 5-8 explains what happens to the controller when you switch from one mode to another.

Table 5-8 Changing Operating Modes

Mode Change

Manual to Automatic Local Setpoint

Description

The Local Setpoint is usually the value previously stored as the Local Setpoint.

PV tracking is a configurable feature which modifies this. For this configuration, when a loop is in manual mode, the local setpoint value tracks the process variable value continuously.

Manual or Auto Local to Automatic Remote SP

Automatic Remote Setpoint to Manual or Auto Local Setpoint

The Remote Setpoint uses the stored ratio and bias to calculate the control setpoint.

Auto bias is a configurable feature which modifies this. When it is selected the transfer from automatic local to automatic remote or from manual remote to automatic remote adjusts the bias based on the local setpoint such that Bias = LSP – (RSP Input x R).

If configured for Local Setpoint Tracking, when the controller transfers out of remote setpoint the last value of the control setpoint is inserted into the local setpoint.

If LSP tracking is not configured, the local setpoint will not be altered when the transfer is made.

4/00 UDC 3300 Controller Product Manual 157