Delta Controls
Access System Manager
Page 15 of 18
Direct Connect Cable (Crossover Cable)
In making direct connect (cross patch) cables, the wires must be crossed over so that transmit, receive and the
bi-directional signals are switched, as follows.
LINK
NET AND
MS/TP N
ETWORKS
& C
ABLING
R
EQUIREMENTS
To ensure network stability and reliable communications, particularly at high speeds on the LINKnet or MS/TP
networks for a number of devices, it is imperative that you adhere to the following network and cabling
requirements:
Item
Description
Cabling
For MS/TP and LINKnet networks it is recommended that you use network cabling that
matches the following specifications:
•
Balanced 100 to 120 ohm nominal impedance Twisted Shielded Pair (TSP) Cable
•
Nominal capacitance of 16 PF/FT or lower
•
Nominal velocity of propagation of 66% or higher
Topology
Ensure the cable is installed as a
daisy chain
from one device to the next.
Max. Controllers
(Access Door
Modules)
The maximum number of controllers per LINKnet network is
12
.
Max. Controllers
for MS/TP
The maximum number of controllers per MS/TP segment is
99
.
Termination
Boards
A termination board (TRM-768)
must
be installed at
each end
of each MS/TP network
segment – or two per MS/TP or LINKnet network. Ensure you do not overlook this in
laying out your network architecture and ordering product.
The LINKnet network must be connected to NET2 of the Access System Manager. The Access Door Modules
reside on the LINKnet network of the Access System Manager.
For more detailed information, including wiring, refer to the RS-485 Network Installation Guide (DOC818-11).
Pin # for left end
Pin # for right end
1
3
6
1
3
2
4
7
8
2
4
5
5
6
7
8
Cable
sheath
1 TX+
2 TX-
3 RX+
4 BD1+
5 BD1-
6 RX-
7 BD2+
8 BD2-
TX+ 1
TX- 2
RX+ 3
BD1+ 4
BD1- 5
RX- 6
BD2+ 7
BD2- 8
