Edwards nEXT nEXT85 - Connection for Serial Control and Monitoring; Connect the Serial Interface to the Customer Control Equipment; Figure 14 Logic Interface Connections - Parallel Control

Figure 14 Logic interface connecons - parallel control
1. 24 - 48 V d.c. electrical supply 2. Fuse
3. Oponal indicator - normal speed 4. Oponal indicator - system OK
5. nEXT pump logic interface 6. Start switch
7. Oponal standby switch 8. Oponal voltmeter to monitor analogue
output
1. 24 - 48 V d.c. electrical supply 2. Fuse
3. Oponal indicator - normal speed 4. Oponal indicator - system OK
5. nEXT pump logic interface 6. Start switch
7. Oponal standby switch 8. Oponal voltmeter to monitor analogue
output
4.6 Connecon for serial control and monitoring
In the serial interface, the pump is controlled through a number of serial commands or
the nST PC soware. You can also check the operaonal status in the serial interface. In
the mul-drop mode, connecon of more than one pump to a single serial port on the
control system is possible.
4.6.1 Connect the serial interface to the customer control equipment
The serial interface is available in RS485 or RS232 opons. Use the slide switch (given
adjacent to the main power lead) to select the serial interface (refer to Figure: Motor
controller status informaon on page 46). To adjust the slide switch, use a small tool to
toggle the slide switch. The default seng of the motor controller is RS232 serial
interface. Replace the round seal to make sure the pump stays IP rated.
CAUTION: PUMP GROUND CONNECTION
Risk of damage to equipment. When you connect the pump to a PC, the 0 V pin on
the RS232 connector can be connected to the ground through the PC. Make sure that
the 0 V rail of the 24 ‑ 48 V d.c. supply is not connected to the ground at other point
(example, at the power supply). If the 0 V rail of the 24 ‑ 48 V d.c. supply will not be
connected to the ground at the PC, use an opto-isolated interface to the PC.
The pump can connect to the RS485 or RS232 serial input on the control equipment or a
PC as shown in Figure: Logic interface connecons - RS232 serial control on page 46 and
Figure: Logic interface connecons - RS485 serial control on page 47. In given
conguraon, the PC is the serial link master and the pump is the slave. The distance
over which the serial link will work is dependent on the dierence in voltage between
the 0 V at the sending and receiving end. If the 0 V reference at the receiving end is in
0.3 V of the 0 V control reference pin on the pump control connector, then the serial link
has to be capable to operate at a distance up to 6 m. For longer distances, an interface
circuit external to the pump can be necessary.
Page 45
B8G000880_D - Installaon