Gardner Denver AUTO SENTRY RS2000 Скачать руководство пользователя

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AUTO SENTRY RS2000 SEQUENCE SYSTEM OPERATION

Each member compressor in the system operates similarly to the Automatic mode of operation. It will
start, load, unload, blowdown, and automatically stop as necessary to meet system demand for air.
There are several differences, however, when running in the Sequence mode.

The pressure shown on the top line of the display is the average system pressure of all the members.
Each member communicates its local pressure through the communications cable, for use by others in
the system for display and control. The system responds to this average. This number will be the same
for all units in the system. To obtain the local package discharge pressure, select the "DIS PRESS"
alternate display on the lower line.

Pressure setpoints are continuously adjusted, depending on the operation of the members. The last lag
unit which is loaded will control its load and unload points to keep the system pressure within the
programmed pressure band, and serves as the trim machine. Any running lead unit will be adjusted for
slightly higher pressures, and will run at or near capacity. The first unloaded lag unit will have its load
pressure adjusted so it will come on line if the system pressure drops to the programmed Load Pressure.
The system is continuously adjusted to maintain the system pressure between the programmed
pressures.

If any lag unit is loaded, any preceding lead unit will be loaded. Its blowdown timer will reset and hold at
full value. This ensures that the last lag unit will always be the first to unload and blow down, and lead
units will be prepared to handle the demand.

When demand exceeds the capacity of the loaded lead compressor(s), the pressure will drop. If a lag
unit is stopped, its restart will be delayed. This delay is the adjustable "Lag Start Delay". This allows time
for lead units and stored air to serve intermittent demands, without starting another compressor. The
next available member accumulates any time spent below the programmed Unload Pressure, and will
start whether there are repeated brief demands or a sustained demand. The Lag Start Delay timer does
not begin timing until the preceding member of the system is loaded.

SEQUENCED SYSTEM CHECKOUT

One of the best indicators of the stability of the system is to compare the local system pressure of a
running unit with the system average pressure. To do this, simply press the [<] or [>] cursor keys until the
lower line of the display shows DIS PRES and the local pressure. In a properly operating system, this
value will be within 1-2 psi of the top line value, and will change only as delivery changes. Rapid and
large changes in local pressure indicate system problems. Ensure that all compressor units are piped to
a common system pressure with adequate storage to handle the plant demands. Select other operating
modes if rapid response to large demand changes is needed.

The system is redundant, and will tolerate any breakdown in communications. If any unit is taken out of
the Sequence mode, other members will "fill the gap" to keep the system operating. If a break should
occur in the communications cable, the compressors will continue to function as two systems, one on
each side of the break. Each will have its own lead unit (Seq 1) and may have lag units (depending on
how many controllers are on that side of the break). Look for a cable break if there are multiple units with
the same Sequence number displayed.

Each controller also monitors the communications data for errors. If these occur, the yellow advisory will
come on, and the controller displays a message to check the communications port. If this message
comes on, and one member changes to "AUTO" operation, then it has been mistakenly programmed with
the same Unit Number as another member. Refer to the sequence adjustments in the programming and
setup instructions above.