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Installation
B800-00-880 Issue A
Refer to
- Logic Interface Connector Pins when you connect the electrical supply to your connector mating
half.
Figure 10 - Logic interface connections - parallel mode
3.6
Connection for parallel control and monitoring
CAUTION
If you use the Normal and Fail lines to drive the coils of d.c. relays you must include a back EMF suppression
diode in parallel with each relay coil to protect the nEXT pump.
1. Connect your control equipment to the control input pins of your logic interface mating half. Refer to
,
which identifies the Logic Interface connector pins. The control inputs are as follows:
Start
Standby Speed
To activate either of these control inputs, you must 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).
Note:
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).
The RS485/RS232 slide switch must be in the (default) RS232 position to use the standby or fail signals in
parallel mode, refer to
.
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.
1. 24-48V d.c. electrical supply
2. Fuse
3. Optional LED indicator - system OK
4. Optional LED indicator - normal speed
5. Current limit resistor for LED
6. nEXT pump logic interface
7. Start switch
8. Optional standby switch
9. Optional voltmeter
to monitor analogue output
Summary of Contents for nEXT240
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