The UDC I used has Firmware V 3505C.
I could not get it to run proportional only on either loop 1 or loop 3 with the input allocation you had.
I changed the PV Source to the same input as the loop number and it seems to work, so that's
Input 1, feedwater flow for Loop 1
Input 2, Drum level for Loop 2
Input 3, Steam Flow as the feedforward variable
Note that
Loop 1 uses a Remote Setpoint, so SP Track = RSP for Loop 1
Loop 2 uses a local setpoint (LSP)
The active setpoint appears with a solid green square to the left of the SP or RSP ID in the bottom display
ALGORITHMS
CONT ALG: PID A
PIDLOOPS: CASCADE
CONT2ALG: PID A
Timer: Disable
IN ALG 1: NONE
IN ALG 2: F FWR2
ALG 2 INA: INPUT 3
ALG 2 INB: LP2OUT
ALG 2 INC: NONE
OUTALG
OUT ALG: CURRENT
INPUT 1 (Feedwater Flow)
IN1 TYPE: 4-20MA
XMITTER1: LINEAR
IN1 HIGH 30.00
IN1 LOW: 0.00
RATIO 1: 1.000
BIAS IN1: 0.0
FILTER 1: 1
INPUT 2 (Drum Level)
IN2 TYPE: 4-20MA
XMITTER2: LINEAR
IN2 HIGH 100.00
IN2 LOW: 0.00
RATIO 2: 1.000
BIAS IN2: 0.0
FILTER 2: 1
INPUT 3 (Steam Flow)
IN3 TYPE: 4-20MA
XMITTER3: LINEAR
IN3 HIGH 30.00
IN3 LOW: 0.00
RATIO 3: 1.000
BIAS IN3: -15.0
FILTER 3: 1
CONTROL (loop 1)
PV Source: Input 1
PID Sets: 1 Only
LSP's : 1 Only
AUTOBIAS: DISABLE
SP Track: RSP
PWR Mode: A RSP (start up in Automatic mode, Remote SP)
SP Hi Limit: 30
SP Lo Limit: 0
Action: Reverse
Out Rate: Disable
Out Hi Lim: 100
Out Lo Lim: 0
CONTROL 2
PV 2 SRC: Input 2
Link LPS: Disable
PID Sets: 1 Only
LSP's : 1 Only
RSP SRC: NONE
SP Track: NONE (changed from RSP)
PWR Mode: A LSP
SP Hi Lim: 100
SP Lo Lim: 0
Action: Reverse
Out Rate: Disable
Out HiLIM: 100
Out LoLIM: 0
When I configure the tuning constants for PB = 100, Rate = 0, Reset = 0.02RPM, both loop 1 and loop 2 outputs drive in the correct directions.
Loop 1's RSP tracks Input 3 (Steam flow) - up when it goes up, down when it goes down
Loop 1's RSP inversely tracks Input 2 (drum level) - down when In2 goes up, up when In2 goes down
Loop 1's output reacts correctly to an increasing In1 PV (feedwater flow); (output decreases on increasing flowrate)
Loop 2's output reacts correctly to an increasing In2 PV (drum level); (output decreases on increasing drum level)
Loop 2's output increases when In 3 (steam flow) increases
Loop 2's output decreases when In 3 (steam flow) decreases