User Manual

Connecting to a HostE–8
Publication 2755-833
Figure E.6 Connecting NEMA Type 4 Decoder to DH485
Network
L
D
P
R
M
N
Shield
TxB
+
TxA –
RS-485
Termina-
tion
Shield
H
o
s
t
Po
r
t
2755-NC17
on Decoder
Host RS-485 Port
*
*
*
*
* Pin designations depend
on host device.
Shield
Only one of the devices in the network must have the cable shield connected to chassis ground.
Do this by connecting shield to pin A instead of pin L.
Enable line termination for the device at each end of the network. To enable line termination,
connect pins M and N together. For all other devices in the network, leave pins M and N open.
SIG GND SIG GND
TxB +
TxA –
The following parameters are fixed for DH485 communications:
8 Data bits
Even parity
1 Stop Bit