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List of PID Loops
There are usually five PID loops operating on the IOC.
Brief descriptions, along with typical PID parameters,
are given below.
- 1. EV9180
-
- Liquid level LL91101 is used to control the
supply JT valve EV9180 so as to
maintain a constant liquid level in the buffer
dewar.
Input |
LL91101 |
Max Pos |
70.00 |
ST |
240.00 |
Set Val |
65.00 |
Min Pos |
see below |
Gp |
2.000 |
|
|
Max Chg |
2.00 |
Gi |
0.003 |
|
|
Min Chg |
0.50 |
Gd |
0.000 |
- 2. EV9180A
-
- Temperature diode TD9178 controls the minimum
position setting of the above PID loop for EV9180.
This ensures sufficient flow through buffer dewar to
keep the its plumbing cold. If the exhaust gas of the buffer
dewar warms much above 6 K, it can no longer be sent
to ESR's cold return line.
Input |
TD9178 |
Max Pos |
90.00 |
ST |
240.00 |
Set Val |
5.80 |
Min Pos |
30.00 |
Gp |
-10.000 |
|
|
Max Chg |
2.00 |
Gi |
-0.020 |
|
|
Min Chg |
0.20 |
Gd |
0.000 |
- 3. EV9178
- Buffer dewar pressure PI91104 is used to control
the cold return valve EV9178 so as
to maintain a pressure in the buffer dewar sufficient
to transfer liquid from the buffer dewar to the magnet dewar
(about 1350 mbar).
Input |
PI91104 |
Max Pos |
100.00 |
ST |
20.00 |
Set Val |
1335 |
Min Pos |
35.00 |
Gp |
-0.5000 |
|
|
Max Chg |
5.00 |
Gi |
-0.020 |
|
|
Min Chg |
0.20 |
Gd |
0.000 |
- 4. EV91127
-
- Separator level LL91113 is used to control the
separator throttle valve EV91127.
Input |
LL91113 |
Max Pos |
0.300 |
ST |
10.00 |
Set Val |
90.000 |
Min Pos |
0.0500 |
Gp |
0.0010 |
|
|
Max Chg |
0.150 |
Gi |
0.0005 |
|
|
Min Chg |
0.005 |
Gd |
0.0000 |
- 5. EV91120
-
- Liquid level meter LL91112 is used to control
the Run valve so that a constant level of LHe is maintained in
tailpiece.
Input |
LL91112 |
Max Pos |
0.7500 |
ST |
20.00 |
Set Val |
75.000 |
Min Pos |
0.0500 |
Gp |
0.0010 |
|
|
Max Chg |
0.150 |
Gi |
0.0020 |
|
|
Min Chg |
0.02 |
Gd |
0.0000 |
Next: Automatic Fill Sequencers
Up: PID Loops
Previous: Description
Christopher D. Keith
2001-08-23