Edwards nXDS10i nXDS15i, Инструкция по эксплуатации

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5.4.1 Hardware configuration
Using the 15
‑
way D
‑
type connector ( Figure: nXDS scroll pump on page 11 , item 7) apply
the following signal configurations to enable the Analogue Speed Control source (refer
to Table: Logic interface connector pins on page 22 ):
Connect the Analogue Speed Enable control input (pin 1) to the 0 V Control Reference
(pin 2).
Connect a suitably calibrated analogue voltage source (0 to + 10 V), for example, (DAC)
to the analogue speed control input (pin 9). Alternatively connect the output of a
potentiometer referenced to the pump reference voltage (pin 11) to the analogue speed
control input (pin 9). Refer to Figure: Logic interface connections - analogue speed
control on page 34 . The 0 V rail of the external voltage source must be connected to the
0 V Control Reference (pin 2) of the pump controller.
5.4.2 Operation
▪ A + 10 V input equates to a mechanical running speed which is equal to: 100% of
the default run speed, that is, 30 Hz.
▪ The minimum running speed provided by the Analogue Speed control source, is
clamped at the minimum Standby Speed Setting, that is, approximately 67% of the
default run speed of 20 Hz.
▪ The maximum running speed provided by the Analogue Speed control source is
clamped by the maximum Standby Speed Setting, that is, 100% of the default run
speed of 30 Hz.
5.5 Auto-run
The auto
‑
run setting configures the pump to start at power
‑
up without any customer
intervention. This parameter is customer configurable via serial communications or using
the START / STOP buttons. Holding down either the START or STOP button, for more than
eight seconds, will enable or disable the auto
‑
run setting. The status of the auto
‑
run
setting is visible via the auto
‑
run LED.
The pump can be stopped using either manual, parallel or serial control modes whilst in
auto
‑
run.
5.6 Use of gas ballast control
The gas ballast control can be used to optimise the performance of the scroll pump for
the application. The performance characteristics of the pump with gas ballast on are
shown in Performance characteristics on page 16 . The position of the gas ballast control
can be changed when the pump is either off or operating.
5.6.1 Gas ballast control
Use the gas ballast control to introduce air into the final stage of the pump. Use of gas
ballast will reduce the condensation of vapours in the pump. The condensates would
contaminate the pump.
There are only two positions, 0 and 1. The gas ballast control knob will rotate 360° in
either direction at 90° intervals.
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A73501880_G - Operation