Edwards nRVi, Instruction Manual

Page: 46 / 100

Figure 8 Logic interface connections - parallel control
1. Start switch 2. nRVi pump logic interface
3. Standby switch (optional)
1. Start switch 2. nRVi pump logic interface
3. Standby switch (optional)
4.9 Connect the analogue speed control
The analogue speed input is a process control source which enables the pump to run at
variable operating speeds. This speed control source is an alternative to standby speed
control.
Using the 15-way D-type connector (
Figure: Pump controls and indicators on page 13 ,
item 3) apply the following signal configurations to enable the analogue speed control
source (refer to Table: Logic interface connector pins on page 25 ).
1. To activate the analogue speed control input, connect the Remote control input
(pin 14) to the 0 V reference (pin 2).
2. Connect the analogue speed enable control input (pin 1) to the 0 V control
reference (pin 2).
3. Connect a suitably calibrated analogue voltage source (0 to +10 V), for example
(DAC), to the analogue speed control input (pin 9).
4. Alternatively connect the output of a potentiometer referenced to the nRVi
reference voltage (pin 11) to the analogue speed control input (pin 9). Refer to
Figure: Logic interface connections - analogue speed control on page 43 . The 0 V
rail of the external voltage source must be connected to the 0 V control reference
(pin 2) of the pump controller.
Page 42
A65901880_D - Installation