Edwards nEXT400 User Manual

The message protocol in the mul‑drop mode is di
erent than the protocol given for the
serial messages in the single pump systems. The dierences in the mul‑drop message
protocol are:
▪ All mul‑drop commands, queries or replies have the rst character as #.
▪ All commands, queries and replies have a header that has:
▪ the address of the node that the message is to
▪ the address of the node that the message is from
▪ Delimiter character: (colon) which separates the two mul‑drop addresses in the
header
▪ The remaining message (command, query or reply) obeys the same protocol as
given for the single pump systems.
▪ The wild card address 99 is useful which means 'any' node.
Aer a pump has been assigned a mul‑drop address, it will ignore the messages in the
format for the single pumps. An individual pump will ignore all the command messages
unless the mul‑drop address matches its own address.
4.8 Connecon for mixed parallel and serial operaon
You can use the parallel interface control inputs to control the pump. At the same me,
you can use the serial interface or the USB service port (using the manufacturer's nST PC
soware) to monitor dierent pump parameters.
Alternavely, you can use the commands sent over the serial interface to control the
pump. At the same me, you can monitor the normal signal and analogue output over
the parallel interface.
Refer to Figure: Logic interface connecon - mixed parallel and serial operaon for the
schemac diagram of a system that demonstrates how to do this. The connecon is a
combinaon of the parallel and serial connecon, given in Connect the parallel control
and monitoring on page 46 and Connecon for serial control and monitoring on page 47.
Opons given in the secons are available in a mixed parallel and serial operaon.
Note:
While serial enable is acve to enable the serial link, the parallel s
tandby and fail signals
are not available.
The mul-drop connecon is shown in Connecon for serial control and monitoring on
page 47. You can use the mul‑drop connecon with mixed parallel and serial operaon.
You can use the mul‑drop connecon with mixed parallel and serial operaon.
You cannot use the parallel interfaces and serial interfaces at the same me to control
the pump. For example, if you start the pump by sending a start command over the
serial interface, you cannot stop the pump by using the start or stop switch on the
parallel interface. To stop the pump, send a serial stop command. Only when the serial
stop command has been received by the pump can any commands sent through the
parallel interface be acted on.
If you use the start switch on the parallel interface to start the pump, you cannot stop
the pump by sending a stop command over the serial interface. To stop the pump, use
the parallel stop switch. The serial interface accepts the start or stop commands only
when you use the parallel interface switch to stop the pump.
04/2022 - ©Edwards Limited
Page 56B80000880_G
B80000880_G - Installaon

Edwards nEXT400 Specifications

General

Brand	Edwards
Model	nEXT400
Category	Water Pump
Language	English