FlexVander NX 910 IO list

Use this page as the terminal, wiring, jumper, and interface reference for a supported FlexVander NX 910 installation.

Hardware overview

Item	Value
Controller	NX 910
Supply	100-260 VAC and 8-36 VDC
Outputs	4 normally-open relay outputs, max. 5 A @ 250 VAC / 30 VDC
Digital inputs	5 inputs. DIN1-DIN4 can be normal digital inputs or S0 inputs. DIN5 can be wakeup input.
Analog inputs	2 inputs, selectable 0-10 VDC or 0-20 mA
Field interfaces	RS485, 1-Wire, and selectable external DC output for supported sensors and accessories

How to use this IO list

For basic FlexVander operation, connect supply, required pump command outputs, and required pump operating feedback signals for the selected program.

Configure the active pump program with FVAPRG.
Configure local push-button behaviour with FVALOCIN.
Configure output pulse time with FVADOUTT#.
Configure stop-contact behaviour with DWCONTACT# where the installation uses that option.

Required basic pump wiring

Supply voltage

Supply	Connection	Terminal	Condition
100-260 VAC	Phase	`P`	Use for AC supply.
100-260 VAC	Neutral	`N`	Use for AC supply.
100-260 VAC	Protective earth	PE terminal	Required with AC supply.
8-36 VDC	Positive	`DCIN`	Use for DC supply.
8-36 VDC	Negative	`XGND`	AC and DC supply can be connected at the same time when required by the cabinet design.

Program 1 basic wiring: two pressure pumps

Program 1 controls one or two pressure pumps without a submersible pump. Wire the command outputs and feedback inputs for each installed pressure pump.

Relay outputs

The relay outputs are potential-free normally-open contacts. FVADOUTT# sets pulse time. DWCONTACT# can change stop-contact behaviour where the installation requires it.

Output	Function	Terminals	Condition
Relay 1	Start pressure pump 1	`R1A`, `R1B`	Required when pressure pump 1 is installed.
Relay 2	Start pressure pump 2	`R2A`, `R2B`	Use only when pressure pump 2 is installed.
Relay 3	Stop pressure pump 1	`R3A`, `R3B`	Required when pressure pump 1 is installed.
Relay 4	Stop pressure pump 2	`R4A`, `R4B`	Use only when pressure pump 2 is installed.

Operating feedback

Connect a compatible pump-running or status signal to each listed input. The signal must be active when the pump is running.

Input	Pump	Terminals	Signal	Condition
`DI2`	Pressure pump 1	`DI2`, `GND`	Pump-running feedback	Required when pressure pump 1 is installed.
`DI3`	Pressure pump 2	`DI3`, `GND`	Pump-running feedback	Use only when pressure pump 2 is installed.

Program 2 basic wiring: submersible pump and pressure pumps

Program 2 controls one submersible pump and one or two pressure pumps. Wire command outputs and feedback inputs for each installed pump.

Relay outputs

The relay outputs are potential-free normally-open contacts. FVADOUTT# sets pulse time. DWCONTACT# can change stop-contact behaviour where the installation requires it.

Output	Function	Terminals	Condition
Relay 1	Start submersible pump	`R1A`, `R1B`	Required when the submersible pump is installed.
Relay 2	Start pressure pump 1	`R2A`, `R2B`	Required when pressure pump 1 is installed.
Relay 3	Start pressure pump 2	`R3A`, `R3B`	Use only when pressure pump 2 is installed.
Relay 4	Stop all pumps	`R4A`, `R4B`	Required stop output for program 2.

Operating feedback

Connect a compatible pump-running or status signal to each listed input. The signal must be active when the pump is running.

Input	Pump	Terminals	Signal	Condition
`DI1`	Submersible pump	`DI1`, `GND`	Pump-running feedback	Required when the submersible pump is installed.
`DI2`	Pressure pump 1	`DI2`, `GND`	Pump-running feedback	Required when pressure pump 1 is installed.
`DI3`	Pressure pump 2	`DI3`, `GND`	Pump-running feedback	Use only when pressure pump 2 is installed.

Interface overview

Interface	Terminals	Use	Continue
Digital inputs	`DI1`-`DI5`, `GND`	Pump feedback and local push buttons	Program 1, Program 2, Local push buttons
Relay outputs	`R1A`-`R4B`	Pump start and stop commands	Program 1, Program 2
Analog inputs	`AI1`, `AI2`, `AGND`	Pressure transmitters and analog field sensors	Pressure control, Mini Weather Station
RS485	`RS485_1+`, `RS485_1-`, `SGND`	Energy meters and supported field instruments	RS485 energy metering
1-Wire	`1Wire`, `1Wire-LED`, `SGND`	Supported temperature or ID accessories	Mini Weather Station

Optional standard features

Local push buttons

Local push buttons are active only when the FlexVander setup uses FVALOCIN. Set the input jumper to match the installed signal type.

Input	Function	Terminals	Signal	Condition
`DI1`	Program 1 pressure pump 1 button	`DI1`, `GND`	Local contact or input signal	Use only when selected by `FVALOCIN`.
`DI4`	Program 1 pressure pump 2 button or program 2 local button	`DI4`, `GND`	Local contact or input signal	Use only when selected by `FVALOCIN`.

Pressure control

Use pressure control only when pressure transmitters are installed. Select voltage or current input from the transmitter nameplate and the selected input setup.

Input	Function	Terminals	Signal	Continue
`AI1`	Pressure line 1	`AI1`, `AGND`	0-10 V or 0-20 mA	`FVAPRESS`, `FVAPTRMODE`
`AI2`	Pressure line 2	`AI2`, `AGND`	0-10 V or 0-20 mA	`FVAPRESSDELAY1/2`

For transmitter wiring details, see Analog transmitter wiring.

RS485 energy metering

Use RS485 energy metering only when an energy meter is installed and assigned to FlexVander. Terminate the RS485 bus only at the two physical endpoints.

Port	Terminals	Use	Condition
RS485 port 1	`RS485_1+`, `RS485_1-`, `SGND`	Energy meter bus	Use a twisted pair and common signal ground.

See Energy meters and Serial RS485 communication for the shared bus requirements.

Mini Weather Station and DataGuard path

Use the controller interfaces below only when the FlexVander installation includes matching sensors and DataGuard reporting.

Sensor path	Interface	Terminals	Condition
Analog level or pressure sensor	Analog input	`AI1` / `AI2`, `AGND`	Use only if the input is not already assigned to pump pressure control.
Temperature or ID accessory	1-Wire	`1Wire`, `1Wire-LED`, `SGND`	Use the accessory wiring supplied with the sensor.
Weather or level instrument	RS485	`RS485_1+`, `RS485_1-`, `SGND`	Use when the instrument is a supported RS485 device on the installation.

See Climate and level sensors for supported serial instruments.

External DC output

Output	Terminals	Use	Condition
12 V / 24 V DC output	`DCOUT`, `SGND`	Supported sensors and accessories	Select the voltage that matches the installed load and current limit.

Hardware jumper reference

The Viking defaults are the delivered FlexVander setup. Change a jumper only when the connected signal or instrument requires a different input type.

Jumper	Function	Viking default	Other setting	Change when
`JPDI1`-`JPDI4`	Input mode for `DI1`-`DI4`	Position `S` for standard FlexVander contact/S0-style wiring	Position `N` for normal positive digital input	The connected feedback or push-button signal requires normal input mode.
`JPAI1`-`JPAI2`	Analog input mode	Current input when pressure transmitter is delivered	Voltage input	The connected transmitter is 0-10 V.
RS485 termination	120 ohm endpoint termination	Installed only when delivered as an RS485 endpoint	Not installed	The controller is not one of the two physical endpoints on the RS485 bus.
DC output selection	12 V or 24 V accessory supply	24 V when delivered for standard sensor supply	12 V	The connected sensor requires 12 V and stays within the current rating.