M-Bus Connection; M-Bus Considerations - Honeywell CENTRA LINE EAGLEHAWK NX Installation & Commissioning Instructions

EAGLEHAWK NX CONTROLLER – INSTALLATION & COMMISSIONING INSTRUCTIONS

M-BUS CONNECTION

The EAGLEHAWK NX controller supports M-Bus Master
functionality via its onboard RS232 / RJ45 socket.
It uses standard PW3/PW20/PW60 converters to connect to
the M-Bus devices.

M-Bus Considerations

Max. no. of M-Bus devices per EAGLEHAWK NX: 60.
Bus Length
• Max. M-Bus length: 350 meters from PW3 / PW20 /
PW60, at communication rates of 9.6 kbps or slower with
shielded, twisted pair cable: J-Y-(St)-Y 2 x 2 x 0,8.
• The M-Bus can be extended to 1,000 meters, depending
upon the communication rate, and provided that the
following electrical limitations are observed:
˗ Bus voltage must at no point fall below 12 VDC
˗ Maximum cable capacitance of 180 nF
For bus length extension, M-Bus repeaters can be used, but
have not been tested by Honeywell. Hence, it is the
responsibility of the installing / commissioning personnel to
ensure proper functioning.
Wiring Topology
M-Bus meters are connected to the bus cable in parallel.
SLAVE 1
PW
EAGLEHAWK
CONVERTER
Fig. 51. Allowed M-Bus wiring topology
Cabling EAGLEHAWK NX to PW3/PW20/PW60
• Use the XW586 cable between the RS232 / RJ45 socket
of the EAGLEHAWK NX and the PW adapters.
• The XW586 cable has a length of 1.8 m, and the pin-out
listed in Table 25.
• In case a third-party cable is used instead of the XW586
cable, the third-party cable must have a max. length of
15 meters and a max. cable capacitance of 2,500 pF.
Table 24. EAGLEHAWK NX RS232 / RJ45 socket
specifications
RJ45 plug,
pin no.
1
2 RxD
3 TxD
4
5 GND
6
7
8
EN1Z-1039GE51 R1218
SLAVE 2 SLAVE 3
RS232 function
8 7 6 5 4 3 2 1
Fig. 52. EAGLEHAWK NX RS232 / RJ45 socket
Table 25. RS232-to-PW cable specifications
RJ45 plug,
RS232 function
pin no.
1 DCD
2 RxD
3 TxD
4 DTR
5 GND
6 DSR
7 RTS
8 CTS
-- Not used
RJ45 plug with clip at front
+5V
Fig. 53. XW586 power / communication cable details
Cabling PW3/PW20/PW60 to M-Bus
• Use shielded, twisted pair cable J-Y-(St)-Y 2 x 2 x 0,8.
• Shielding is especially recommended when the M-Bus
cable is installed in areas with expected or actual electro-
magnetic noise. Avoiding such areas is to be preferred.
• Connect the shield to a noise-free earth ground – only
once per M-Bus connection.
• Power the EAGLEHAWK NX controller and the PW M-Bus
Adapter with separate transformers – see WARNING
below.
NOTE: If, alternatively, only a single transformer is available,
when connecting a laptop, PC, web browser, CL-
rd
Touch, or 3 -party touch panel to the USB 2.0
Device Interface on the front of the EAGLEHAWK
NX controller, use an optical isolator for the USB
connection or substitute an M-Bus Mikro-Master
USB (Relay GmbH, D-33106 Paderborn) for the PW
M-Bus Adapter.
46
9-Pin sub-D
connector pin no.
1
2
3
4
5
6
7
8
9
RS232 plug
sub-D male
SHIELD
XW586