Johnson Controls Frick QUANTUM LX Manual page 13

If the Difference is
Proportional Band:
Capacity Change = Lower Cycle Time
After the capacity decrease has been calculated, the
leader then finds the compressor whose capacity
should be changed. To make this determination, the
leader sorts all the compressors based on their start
number. Beginning at the compressor with the
highest start number, the leader finds the last
compressor on the list that is running and whose
Minimum Capacity
capacity is above its
two compressors are currently running at or below
Minimum Capacity
their
allow any additional compressors to unload. This will
allow the Suction Pressure to continue to drop and
will cause the leader to turn off one of the unloaded
compressors. If the leader sees that only one
compressor is running in its system, it will continue to
unload the compressor
Automatic Capacity Mode Minimum Slide Valve
Position
setpoint.
If the selected compressor is running the Quantum™
LX software, the capacity decrease is subtracted from
the compressor's current capacity. This new value is
then sent to the compressor as its
Command , and that compressor will try to decrease
its capacity to match the Command value.
If the selected compressor is controlled by a
Quantum™ 1-4 or a Plus panel, the capacity decrease
is interpreted as the time-period for an unload pulse
and is sent to the compressor as an unload command.
The follower compressor will then turn on its
unload output for the given number of seconds.
High Stage/Booster
The High Stage System Link
a system of Booster compressors to a system of High
Stage compressors. For example, if the Booster
compressors are setup on System #1 and the High
Stage Compressors are on System #2, the High Stage
System Link setpoint from System #1 would be set as
System 2
.
When the Booster System's leader wants to start the
first Booster compressor, it first checks that a Booster
compressor is available to run and then sends a signal
to the High Stage System's leader telling it to start a
High Stage compressor. If all the High Stage
compressors are off, the High Stage System's leader
will start its first compressor, regardless of what the
High Stage Control Input
Booster System's leader observes that a High Stage
compressor is running, it will allow a Booster
compressor to start.
After the first High Stage compressor begins to run,
compressors in both systems will cycle on and off as
FRICK ® QUANTUM™ LX COMPRESSOR CONTROL PANEL
OPERATION - SERVICE
greater than the Lower
setpoint. If
setpoints, the leader will not
down to the leader's
Capacity
setpoint is provided to tie
is reading. When the
their Control Inputs move up and down. The only
stipulation to the control strategy is that one High
Stage compressor must always remain on as long as
at least one Booster compressor is running. If all the
Booster compressors turn off, the High Stage
compressor can then turn off as well.
Establish Sequencing Communications Using An
Ethernet Connection
Perform the following steps on each panel that will be
part of the sequencing group:
 From the Main Menu, select [Session].
At the Session menu, set the User Level to

[2], and enter a password of [20], then press
[Submit]. This will set the user access to
level 2, which is the minimum level needed
to access the sequencing feature.
 Next press [Menu] > [Configuration] and
select [Compressor].
 On the Compressor Configuration screen, tab
down to enable [Sequencing], then tab over
to [Mode 3] and enable it. Press [Submit].

Once again select [Menu] > [Setpoints] >
[Sequencing] then [System 1 Setup].

On the [System 1 Setup] screen, tab to
Sequencing and [Enable] it. Next set the
Control Setpoint to the value that you wish
to control to. Set the Minimum Runtime to
[10 Min], and set High Stage System Link as
[None].

Now set Sequencing ID #1 as [last octet of
1 st Compressor's IP address], set the Start #
as [1], Compressor and Capacity Modes as
[Remote Seq.] and Minimum Capacity as
proper value.

Next set Sequencing ID #2 as [last octet of
2 nd Compressor's IP address], set the Start #
as [2], Compressor and Capacity Mode as
[Remote Seq.] and Minimum Capacity as
proper value.

Go to [Menu] > [Modes]. Verify that the
Active Mode is set to either Mode 3 or Mode
4.

Finally, go to the [Menu] > [Operating
Values] > [Sequencing]. Ensure that a status
other than not communicating is present for
both machines.
This concludes the Sequencing setup.
090-022 O (NOV 09)
Page 13