Edwards, nEXT Turbomolecular Pumps, nEXT240, nEXT300 and ...

B800-00-880 Issue B
The pump will then accelerate to full operating speed. The green indicator LED will illuminate when the pump
reaches Normal speed. (This is 80% of full rotational speed by default but you may have selected a different value to
suit your application).
4.5.3 Standby speed
To run the nEXT pump at Standby Speed, send the following command over the serial communications link:
Operation
The reply you receive will be as follows:
Command ! C 8 6 9 sp 1 cr
Reply * C 8 6 9 sp r cr
If the pump is currently below Standby Speed then it will accelerate until it reaches Standby Speed. If it is running
faster than Standby Speed, it will decelerate until Standby Speed is reached.
To return the pump to full speed, send the following command:
The reply you receive will be as follows:
Command ! C 8 6 9 sp 0 cr
4.5.4 Stop the pump
Reply * C 8 6 9 sp r cr
To stop the nEXT pump, send the following command over the serial communications link:
The reply you receive will be in the following format:
Command ! C 8 5 2 sp 0 cr
On successful receipt of the stop command, the pump rotor will decelerate to rest.
4.5.5 Temperature readings
Reply * C 8 5 2 sp r cr
You can monitor the temperatures of both the pump motor and the internal electronics of the nEXT pump by sending
the following query:
Command ? V 8 5 9 cr
The reply you receive will be as follows, where the first number is the motor temperature and the second number
the internal Controller temperature, both measured in °C:
Reply = V 8 5 9 sp d d d ; d d d cr
4.5.6 Link parameter readings
You can monitor the internal voltage, current and motor power of the nEXT pump by sending the following query:
Command ? V 8 6 0 cr
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