Two Loops Of Control - Honeywell UDC3500 Product Manual

Monitoring and Operating the Controller
Operation
Operate the Auto/Manual Station as follows:
Set the Local Setpoint 2 to 0 % of the Input 2 range.
These features work with the Auto/Manual Station.
• In the SP RAMP set up list, SP PROG (acts on SP1 for backup operation).
• In the SP RAMP set up list, SP RAMP (acts on SP1 for backup operation).
• In the CONTROL set up list, ACTION as DIRECT or REVERSE for the backup
PID A operation.
• The PD+MR action is forced to be DIRECT as required for the pass through of
the output signal.

4.17 Two Loops of Control

Introduction
As an option, this instrument can operate using two independent loops of control or
internal Cascade Control.
Two Independent Loops
See Functional Overview Block Diagrams for Loop 1 and Loop 2 (Figure 4-3) for
selections based on these diagrams.
The following rules apply for two independent loops:
•
Control and Alarm Outputs are allocated per Table 2-6 and Table 2-7.
•
Current output on Loop 2 requires that either Second Current Output or Third
Current Output be installed.
•
Loop 2 relay output is always dedicated to relay outputs 3 and 4.
•
No Three Position Step output on Loop 2.
230 UDC3500 Universal Digital Controller Product Manual 3/07