Edwards nEXT200200 - Figure 11 Controller Status Information

Figure 11 Controller status in
formaon
1. Standby speed increase buon 2. RS485 / RS232 switch
3. Controller connector socket 4. Standby speed reduce buon
5. Alarm LED 6. Status LED
7. Normal LED
1. Standby speed increase buon 2. RS485 / RS232 switch
3. Controller connector socket 4. Standby speed reduce buon
5. Alarm LED 6. Status LED
7. Normal LED
CAUTION: PUMP GROUND CONNECTION
Risk of damag
e 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 sho
wn in Figure: Logic interface connecons - RS232 serial control on page 43 and
Figure: Logic interface connecons - RS485 serial control on page 43. 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 of to operate at a distance up to 6 m. For longer distance, an interface
circuit external to the pump can be necessary.
The soware in the pump can operate with the other pumps connected to a single serial
link master. This is a mul-drop mode. The RS485 opon is recommended for the mul-
drop mode. When the RS232 opon is selected, more hardware is necessary to link
number of pump units to a single serial link master. A concept drawing of one possible
arrangement is shown in Figure: Conceptual diagram for mul-drop connecon using
RS232 interface on page 45. When the RS485 opon is selected, it is easy to connect
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tallaon