Start-Up and Shutdown
RTAF-SVX001K-EN
65
Running (Lag Compr/Circuit Start - Run)
The figure below shows a typical start and run sequence
for the lag compressor and its circuit.
Figure 43.
Sequence of operation: running (lag compressor/circuit start nd run)
*
Note: The decision to stage on or off another compressor is determined by
the Average Running Compressor Load Command, Water Temperature Error, and Time Since Last Stage
All
Compressors
Running
Chiller and Both Circuit
Modes are “Running”
Modulate
Compressor for
Capacity Control
De-energize
Oil Heaters
Of Lag Circuit
Control Both Circuit
Condenser Fans for
Optimum Differential
Pressure,
ƒ(Cprsr Spd, OA Temp)
6
6
/
/
/
/
6
6
6
6
6
6
1
1
1
2
2
2
/
/
/
/
2
2
2
2
2
2
2
2
2
0
0
0
1
1
1
2
2
2
-1
1
1
2
2
2
/
/
/
/
2
2
2
2
2
2
1
1
1
1
1
1
/
/
/
/
1
1
1
2
2
2
0
0
0
1
1
1
2
2
2
Enforce All Running Mode Diagnostics for Chiller, Lead Compressor and its Circuit
Modulate
Compressor
for Limit
Control
Modulate Compressor
for
Capacity Control
/
/
/
/
6
6
6
1
1
1
/
/
/
/
/
/
2
2
2
/
/
/
/
2
2
2
2
2
2
/
/
/
/
/
0
0
0
1
1
1
2
2
2
-
7
7
7
/
/
/
/
7
7
7
2
2
2
/
/
/
/
/
4
4
4
/
/
/
/
4
4
4
2
2
2
/
/
/
/
/
0
0
0
1
1
1
2
2
2
Running
6/
6
6 13/
/
3
3 2012
7
7
7
/
/
/
/
/
/
/
7
7
7 2
2
2
2
2
/
//
/
/
/
/
3
3
3
/
/
/
/
3
3
3
2
2
2
/
/
/
/
/
0
0
0
1
1
1
2
2
2
-
8
8
8
/
/
/
/
8
8
8
1
1
1
/
/
/
/
/
/
4
4
4
/
/
/
/
4
4
4
2
2
2
/
/
/
/
/
Running
7/
7
7 24
2
2 /
4
4 2012
6/
/
/
6
6 1
1
1
1
1
1
3
3
3
3
/
/
/
/
/
3
3
3
3
3
2
2
2
2
2
2
2
2
0
0
0
0
0
0
0
0
1
1
1
1
1
1
2
2
2
2
2
2
Milest
s
s on
n
n
n
n
n
e
e
e
e
D
D
D
D
e
e
e
e
e
e
e
e
e
e
D
D
D
D
D
D
D
D
D
s
s
s
s
c
c
c
c
s
s
s
s
s
s
r
r
r
r
i
i
i
i
i
p
p
p
p
p
t
t
t
t
p
p
p
p
p
i
i
i
i
i
o
o
o
o
n
n
n
n
Exit
Limit Mode
Enter
Limit Mode
0
0
0
/
/
/
/
0
0
0
2
2
2
/
/
/
/
/
8
8
8
/
/
/
/
8
8
8
2
2
2
/
/
/
/
/
0
0
0
1
1
1
2
2
2
-
1
1
1
2
2
2
/
/
/
/
2
2
2
1
1
1
/
/
/
/
/
/
1
1
1
/
/
/
/
2
2
2
/
/
/
/
/
0
0
0
1
1
1
2
2
2
Running
Energize Maximum
Capacity Relay after the
Adjustable Filter Time
(0 to 1500 Seconds)
Continue
Running
(All
Cprsrs &
Max
Capacity
Maximum Capacity
Submode
9
9
9
/
/
/
/
9
9
9
1
1
1
/
/
/
/
/
/
1
1
1
/
/
/
/
2
2
2
/
/
/
/
/
0
0
0
1
1
1
2
2
2
-
1
1
1
0
0
0
/
/
/
/
0
0
0
3
3
3
/
/
/
/
/
0
0
0
/
/
/
/
0
0
0
2
2
2
/
/
/
/
/
0
0
0
1
1
1
2
2
2
Running
8/
//
8 1
// 3/
//
3 2
// 012 - 9/
//
9 1
// 1/
//
2
// 0
0
0
1
1
2
Running
Lag Circuit:
Running Limit
9/
9
9 11/
/
1 2012
8/
8
8 13/
/
3
3 2012
1
1
1
or
0
0
0
r
/
/
/
0
0
0
0
30
0
/
/
0
0
2012
2
2
All Compressors Running
At or Near Max Capacity
(Unable to Achieve CWSP)
Modulate EXV for
Pressure Control