B800-00-880 Issue D
Page 36
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Installation
3.6
Connection for parallel control and monitoring
CAUTION
If using the normal and fail lines to drive the coils of d.c. relays, include a back EMF suppression diode in parallel
with each relay coil to protect the nEXT pump.
1. Connect the customer control equipment to the control input pins of the customer logic interface mating half.
Refer to
Table 11
, which identifies the logic interface connector pins. The control inputs are as follows:
Start
Standby speed
To activate either of these control inputs, connect the control input pin to the 0 V control reference.
To start the pump, connect pin 3 (Start / Stop) to pin 2 (0 V Reference). To stop the pump, break the connection
between pin 3 and pin 2. To put the pump into standby, connect both pin 4 (Standby) and pin 3 (Start/Stop) to pin 2
(0 V reference).
Notes:
1 Serial enable is also a control input but is not required in a system operating purely under parallel
control. Make sure that there is no connection to serial enable (pin 5).
2 The RS485/RS232 slide switch must be in the (default) RS232 position to use the standby or fail parallel
interface signals, refer to
Section 3.7.1
.
2. To monitor analogue output, connect the customer control equipment to the pump analogue output (pin 9) and
to pin 2 of the customer logic interface mating half.
When the pump is shipped, the analogue output is configured to monitor pump rotational speed. To monitor other
parameters, re-configure the nEXT pump using commands over the Serial Interface. Refer to
Section 3.7
for further
details.
3. To monitor the normal status output, connect the customer control equipment to the normal status output (pin
15) and to pin 2 of the customer logic interface mating half. The output can be used to control other devices in
the pumping system. The output can drive a low power relay of up to 24 V coil rating (up to 20 mA).
4. To monitor the fail status output, connect the customer control equipment to the fail output (pin 7) and to pin 2
of the customer logic interface mating half. The output can be used to control other devices in the 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 the nEXT pump to be controlled and to be interrogated as to its operational status using
a number of serial commands. There is a multi-drop mode that allows for the connection of more than one nEXT pump
to a single serial port on the control system.
3.7.1
Connect the serial interface to the customer 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.
