Connecting Eaglehawk Nx Via Its Rs485-2 Interface To A Bacnet Ms/Tp Bus - Honeywell CENTRA LINE EAGLEHAWK NX Installation & Commissioning Instructions

EAGLEHAWK NX CONTROLLER – INSTALLATION & COMMISSIONING INSTRUCTIONS

Connecting EAGLEHAWK NX via its RS485-2 Interface to a BACnet MS/TP Bus

With regards to Fig. 47 and Fig. 48, please note the following:
NOTE: Always power each EAGLEHAWK NX controller and the connected BACnet MS/TP modules via separate transformers.
NOTE: For "L," see section "RS485 Standard" on pg. 10.
NOTE: If any of the devices are electrically isolated, it is recommended that those devices be connected to signal ground. See
section "RS485 Standard" on pg. 10.
NOTE: Between devices equipped with non-isolated RS485 bus interfaces, potential differences of max. ±7 V are allowed.
Further, this bus should not extend beyond a single building.
Example 1: Single EAGLEHAWK NX Controller and Connected BACnet Modules (with inserted termination
resistor)
EAGLE-
HAWK NX
2930 31
GND-2
+5V GND-2
Module #2
550 OHM 130 OHM 550 OHM
RS485-2 (+) RS485-2 (-)
NO EFFECT ON RS485-2
1 2
BACnet
Module #1
F1
24 V
230 V
Fig. 47. Connection of a single EAGLEHAWK NX controller via its RS485-2 interface to a BACnet MS/TP Bus
The termination resistor must be inserted directly into the terminals of the last BACnet MS/TP module.
Example 2: Multiple EAGLEHAWK NX Controllers and Connected BACnet Modules
EAGLE-
HAWK NX
29 30 31
GND-2
+5V GND-2
Module #2
550 OHM 130 OHM 550 OHM
RS485-2 (+) RS485-2 (-)
NO EFFECT ON RS485-2
1 2
BACnet
Module #1
F1
24 V
230 V
Fig. 48. Connection of multiple EAGLEHAWK NX controllers via their RS485-2 interfaces to a BACnet MS/TP Bus
EN1Z-1039GE51 R1218
BACnet BACnet
Module #3
*CONNECT GND, IF AVAILABLE.
EAGLE-
HAWK NX
24 25 26
GND-1
BACnet
+5V
ISO
47 kOHM 47 kOHM
RS485-1 (+) RS485-1 (-)
MID
1 2
BACnet
Module #3
F1
*CONNECT GND, IF AVAILABLE.
24 V
230 V
L
BACnet
Module #4
L
EAGLE-
HAWK NX
GND-1
BACnet
GND-1 +5V
ISO
Module
47 kOHM
1
24 V
230 V
42
BACnet BACnet
Module #N-1 Module #N
EAGLE-
HAWK NX
24 25 26 29
GND-1 +5V
47 kOHM 550 OHM 130 OHM
RS485-1 (+) RS485-1 (-) RS485-2 (+)
MID
2 1 2
BACnet BACnet
Module #N-1 Module #N
F1 F1
24 V
230 V
R
T
120 OHM
30 31
GND-2
GND-2
550 OHM
RS485-2 (-)
NO EFFECT ON RS485-2