Operating Two Loops Of Control - Honeywell UDC 3300 Product Manual

5.15 Operating Two Loops of Control

Loop operation
Operating modes and
setpoint source
Keyboard operation
Accutune
Setpoint ramp or SP
programming
Digital inputs (remote
mode switching)
Output override Hi/Lo
select
4/00
Operation of two individual loops of control is identical to operating a
single loop of control except that TUNING 2 group applies to Loop 2 only
and two PID sets, 3 and 4, are available. TUNING group applies to Loop
1 with PID sets 1 and 2 applicable.
The rules for Auto/Manual modes and changing setpoint sources are the
same as single loop operation.
Note that the loop being displayed is the only loop affected by normal
keyboard operation. However, either loop can be reconfigured when in the
Set Up mode regardless of which is being displayed during normal
operation.
Two independent loops or cascaded loops can be tuned at the same time,
if configured.
Either loop or both loops can be configured for a single setpoint ramp
operation by enabling the desired loop or loops (see Section 3 –
Configuration).
An "H" or "R" will appear when applicable, depending upon which loop
is being displayed.
The RUN/HOLD operation is shown in Table 5-15 Procedure for Running
a Setpoint Ramp.
Digital Input 2 is dedicated to Loop 2 and Digital Input 1 is dedicated to
Loop 1 when two loops or Cascade control is configured.
Output Override allows you to select the higher of Output 1 and Output 2
(Hi Select) or the lower of Output 1 and Output 2 (Lo Select) to appear at
Output 1 terminals to drive the final control element. Refer to Section 5.12
for Override rules and block diagram.
Override prompts appear under the Algorithm Set Up group, function
prompt OUT OVRD.
UDC 3300 Controller Product Manual 181