Edwards nEXT200200, Инструкция по эксплуатации

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If you use the controller to control a TAV solenoid valve, there is a 2
‑
second delay
between receiving a stop command (or detecting a fault condition) and opening the vent
valve. The delay allows time for gauges, valves and other equipment to be switched off
before venting occurs.
The green indicator LED on the controller will extinguish as rotational speed drops below
normal speed. At very low speeds, the yellow indicator LED flashes. The yellow indicator
LED extinguishes when the pump has stopped.
6.7 Operation at extreme conditions
6.7.1 Operation with high inlet pressure
If the pump inlet pressure increases, the power supplied to the pump motor will
increase to counteract the gas frictional load.
The pump rotational speed will stay constant until the peak power level is reached. After
the peak power level, the speed of the pump will start to decrease.
If the pump speed decreases below 50% of full rotational speed, the timer will start (if it
is enabled). If the speed does not recover to more than 50% speed before the timeout
period expires, the pump will stop and display a fail signal. If the timer is disabled, the
pump will stop immediately and display a fail signal if the speed decreases below 50% of
the full rotational speed. Refer to Electrical data on page 24 for the maximum power
delivered to the pump. Refer to Table: nEXT pumps technical data on page 17 for
maximum permitted inlet pressure.
6.7.2 Operation at high temperatures
Temperature sensors in the pump mechanism and electronics are monitored by an
internal system. If the system detects that internal temperatures are too high, the power
supplied to the pump motor is reduced, the pump can possibly not be able to maintain
full rotational speed if it is too hot.
If the pump speed decreases below 50% of the full rotational speed, the timer will start
(if it is enabled). If the speed does not recover to more than 50% speed before the
timeout period expires, the pump will stop and display a fail signal. If the timer is
disabled, the pump will stop immediately and display a fail signal if the speed decreases
below 50% of the full rotational speed. Refer to Operation and storage environment on
page 22 for pump operating ranges. Refer to Cooling on page 54 for advice on pump
cooling.
6.7.3 Protection against over-speed
Control software in the motor controller control the pump rotational speed and prevents
the operation of the pump more than its normal full rotational speed.
If the control software fails, the motor controller has a built
‑
in safety circuit that checks
if the pump is operating at over
‑
speed. If an over
‑
speed condition is detected, the motor
controller automatically stops the power to the pump motor, slows the pump and stop.
The motor controller signals a fail condition if over
‑
speed is detected.
If the pump is operating at over
‑
speed, set the pump to off and contact us or the
supplier.
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B85200880_D - Operation