Grundfos NBE Series - 5.8.9 Signal cables; 5.8.10 Bus connection cable

5.8.9 Signal cables
Use screened cables with a cross-sectional area of minimum 28
AWG (0.5 mm
2
) and maximum 16 AWG (1.5 mm
2
) for the external
on/off switch, digital inputs, setpoint and sensor signals.
The wires in the motor terminal box must be as short as possible.
5.8.9.1 Connecting signal cables
1. Connect the screens of the cables to the frame at both ends
with good connection. The screens must be as close as
possible to the terminals.
TM021325
Model J
TM082967
Model K
2. Connect the signal cables to the terminals.
3. Depending on the model, tighten one or two earth clamp
screws.
See the section on functional modules.
5.8.10
Bus connection cable
5.8.10.1 Connecting a 3-core bus cable, GENIbus
For the bus connection, use a screened 3-core cable with a cross-
sectional area of minimum 28 AWG (0.5 mm
2
) and maximum 16
AWG (1.5 mm
2
).
• If the motor is connected to a unit with a cable clamp which is
identical to the one on the product, connect the screen to the
cable clamp.
• If the unit has no cable clamp, leave the screen unconnected at
this end.
A
Y
B
A
Y
B
TM070223
5.8.10.2
Connecting a 3-core bus cable, Modbus
A screened, twisted-pair cable must be used. The cable screen
must be connected to protective earth at both ends.
Recommended connection
Terminal
Modbus Colour code Data signal
A D1 Yellow Positive
B D0 Brown Negative
Y Common/GND Grey Common/GND
Fitting the cable
1. Connect the yellow conductor to terminals D1 and A.
2. Connect the brown conductor to terminals D0 and B.
3. Connect the grey conductor to terminals Common/GND and Y.
4. Connect the cable screens to protective earth via the earth
clamp.
D1
GND
D0
A
Y
B
TM083382
It is important to connect the screen to protective earth
through the earth clamp and to connect the screen to
protective earth in all units connected to the bus line.
5.8.10.3 Connecting a 2-core bus cable
• Connect a screened 2-core bus cable as follows:
A
1
2
Y
B
A
Y
B
1
2
TM070221
5.8.10.4 Connecting an Ethernet cable
For the USA and Canada, the connection of Ethernet cables must
be done by connecting the Ethernet cable screen to an earth clamp
on the terminal box, as shown below.
TM085827
Connecting an Ethernet cable
The Ethernet cable must be rated at least Cat5e/Cat6 with
screening.
The recommended Ethernet cable types for earth clamp
applications are SF/UTP, S/FTP or SF/FTP, where the cable screen
consists of both a braided and a foil screen.
5.8.10.5
Bus signal
The product enables serial communication via an RS-485 input.
The communication is carried out according to the Grundfos
GENIbus protocol and enables connection to a building
management system or another external control system.
Via a bus signal, you can remote-set operating parameters, such as
setpoint and operating mode. At the same time, the product can
provide status information about important parameters, such as the
actual value of the control parameter, input power and fault
indications, via the bus.
Contact Grundfos for further information.
23
English (US)