ABB ACH550-UH HVAC, User Manual

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ACH550-UH User’s Manual 1-155
Parameters
4010 SET POINT SEL 0…2, 8…17, 19…20 1 0 (
KEYPAD
)

Defines the reference signal source for the PID controller.
• Parameter has no significance when the PID regulator is by-passed (see 8121
REG BYPASS CTRL
).
0 =
KEYPAD
– Control panel provides reference.
1 =
AI
1 – Analog input 1 provides reference.
2 =
AI
2 – Analog input 2 provides reference.
8 =
COMM
– Fieldbus provides reference.
9 =
COMM
+
AI
1 – Defines a fieldbus and analog input 1 (
AI
1) combination as the reference source. See Analog input
reference correction below.
10 =
COMM * AI
1 – Defines a fieldbus and analog input 1 (
AI
1) combination as the reference source. See Analog input
reference correction below.
11 =
DI
3
U
,4
D
(
RNC
) – Digital inputs, acting as a motor potentiometer control, provide reference.
•
DI
3 increases the speed (the U stands for “up”)
•
DI
4 decreases the reference (the D stands for “down”).
• Parameter 2205
ACCELER TIME
2 controls the reference signal’s rate of change.
• R = Stop command resets the reference to zero.
• NC = Reference value is not copied.
12 =
DI
3
U
,4
D
(
NC
) – Same as
DI
3
U
,4
D
(
RNC
) above, except:
• Stop command does not reset reference to zero. At restart the motor ramps up, at the selected acceleration rate,
to the stored reference.
13 =
DI
5
U
,6
D
(
NC
) – Same as
DI
3
U
,4
D
(
NC
) above, except:
• Uses digital inputs
DI
5 and
DI
6.
14 =
AI
1+
AI
2 – Defines an analog input 1 (
AI
1) and analog input 2 (
AI
2) combination as the reference source. See
Analog input reference correction below.
15 =
AI
1*
AI
2 – Defines an analog input 1 (
AI
1) and analog input 2 (
AI
2) combination as the reference source. See
Analog input reference correction below.
16 =
AI
1-
AI
2 – Defines an analog input 1 (
AI
1) and analog input 2 (
AI
2) combination as the reference source. See
Analog input reference correction below.
17 =
AI
1/
AI
2 – Defines an analog input 1 (
AI
1) and analog input 2 (
AI
2) combination as the reference source. See
Analog input reference correction below.
19 =
INTERNAL
– A constant value set using parameter 4011 provides reference.
20 =
PID
2
OUT
– Defines PID controller 2 output (parameter 0127
PID
2
OUTPUT
) as the reference source.
Analog input reference correction
Parameter values 9, 10 and 14…17 use the formula in the following table.
Where:
• C = Main reference value
( =
COMM
for values 9, 10 and
=
AI
1 for values 14…17)
• B = Correcting reference
( =
AI
1 for values 9, 10 and
=
AI
2 for values 14…17).
Example:
The figure shows the reference source curves for
value settings 9, 10 and 14…17, where:
• C = 25%.
• P 4012
SETPOINT MIN
= 0.
• P 4013
SETPOINT MAX
= 0.
• B varies along the horizontal axis.
Group 40: Process PID Set 1
Code Description Range Resolution Default S
Value setting Calculation of the AI reference
C + B C value + (B value - 50% of reference value)
C * B C value · (B value / 50% of reference value)
C - B (C value + 50% of reference value) - B value
C / B (C value · 50% of reference value) / B value
120
100
80
60
40
20
0
0
100%
9, 14 (+)
16 (-)
10, 15 (*)
17 (/)
B