Section 3
SUPERVISOR CONTROLLER SEQUENCING
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machine will stop, and be held stopped.
The following table describes how the other inputs work:
Local/Master Load/Unload Operation
Open Open Normal load and unload
Open Closed Force unload
Closed Open Force load, unload at P1 max - 3
Closed Closed Force unload
The Local/Master Output(K8) is closed when the Local/Master Input is on and the machine
is not in E-stop or Stop. The Local/Master Output is a relay contact that can handle 110VAC
at 6 amperes.
Description of Typical Compressor System in Sullair Sequence Mode
MACHINE PREPARATION PRIOR TO SEQUENCING
1. Complete all machine startup procedures for stand-alone operation for the machines that
are to be sequenced together per the compressor operators manual.
2. Relocate the P2 signal for all machines to read the common header pressure. To recal-
ibrate the P2 signal for each machine so that they match within 1 psi of each other, use
the system display mode described later to view P2 on all machines. Recalibrate P2 on
each machine to match P2 on the other machines.
3. Program each machine with a different COM ID number (i.e.1, 2, 3, etc.).
4. Set UNLOAD psi, LOAD psi, BAUD RATE, SEQUENCE mode (COM ID or HOURS),
LAST COM, LOWEST and RECOVER time (normally set at 10) the same for each
machine (except for VSD applications). Leave ROTATE hours disabled except for the
specific application described. Set all SEQ HRS the same unless it is desired to force
certain machines to initially run more than others in the HOURS mode.
5. Set the machines to run in AUTO mode. Press the REMOTE key to arm the machines
for sequencing. Machines will start immediately if the P2 system pressure is low. On a
fully pressurized system the machines will go into SEQ STOP until a demand is seen.
The following operation describes how machines are started, fully loaded and unloaded
by the sequencing mode selected. The AUTO mode provides the means for each
machine to SEQ STOP by timing out on its unload timer (UNLD TIM) when the sequenc-
ing order decides the machine is to be unloaded.
SYSTEM OPERATION
For this example three machines are in a system with the load pressure set at 100, unload
at 110 psig (7.6 bar), lowest pressure at 90 psig (6.2 bar), and Recovery Time at 10 sec-
onds(default value). All machines are in sequence stop (top line of the display is SEQ
STOP). When the pressure drops below 102 psig (7.6 bar) a timer starts counting down from
120 seconds, if the pressure continues to drop the timer will count down faster. When the
timer expires or the pressure drops below 90 psig (6.2 bar) the first machine is started. If the
pressure does not go above 90 psig (6.2 bar) for 10 seconds (Recovery Time) the next
machine will start and so on until all machines are started.