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

B800-00-880 Issue B
Installation
2. To monitor Analogue Output, connect your control equipment to the pump Analogue Output (pin 9) and to pin 2
of your logic interface mating half.
When you receive your pump, the Analogue Output will be configured to monitor pump rotational speed. If you wish
to monitor any other parameter you must re-configure your nEXT pump using commands over the Serial Interface.
Refer to Section 3.7 for further details.
3. To monitor the Normal status output, connect your control equipment to the Normal status output (pin 15) and
to pin 2 of your logic interface mating half. You can use the output to control other devices in your pumping
system. The output can drive a low power relay of up to 24 V coil rating (up to 20mA).
4. To monitor the Fail status output, connect your control equipment to the Fail output (pin 7) and to pin 2 of your
logic interface mating half. You can use the output to control other devices in your pumping system. The output
can drive a low power relay of up to 24 V coil rating.
3.7 Connection for serial control and monitoring
The Serial Interface allows you to control the nEXT pump and to interrogate its operational status using a number of
serial commands. There is a multi-drop mode that allows you to connect more than one nEXT pump to a single serial
port on your control system.
3.7.1 Connect the serial interface to your control equipment
The serial interface is available in RS485 or RS232 options which can be selected using the slide switch located above
the controller connector, shown in Figure 12. To adjust the slide switch simply remove the plastic connector cover
on the controller and toggle the slide switch using a small tool. Sliding the switch to the right will enable RS232 serial
interface and to the left will enable RS485 serial interface. The controller default setting is RS232 serial interface.
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