Micromod Micro-DCI: 53MC5000 MicroLink - Manual (Page 14)

4.1.2 SUPERVISOR-PC UNIT
The 53SU5000 SUPERVISOR-PC unit can be ordered with MicroLink communications capabilities,
or an existing unit that is an IBM AT-compatible PC (see IB 53SU5000, Section 2, for specified ven-
dor model numbers and minimum configuration) can be field upgraded with installation of a Mi-
croLink SUPERVISOR board (p/n 686B619) and software. Standard Datalink SUPERVISOR
boards (p/n 686B574) can not be upgraded to MicroLink network functionality. It is possible to
have one standard Datalink SUPERVISOR board and one MicroLink SUPERVISOR board, or two
MicroLink SUPERVISOR boards, in the same PC unit. The SUPERVISOR board can be installed
in any full length slot of an IBM AT-compatible PC as described in IB 53SU5000, Section 2 (Install-
ing the SUPERVISOR-PC Cards). If the SUPERVISOR-PC unit is installed on a redundant net-
work, then the redundant MicroLink card must be installed in the slot immediately to the right of the
MicroLink SUPERVISOR board. Installation of the MicroLink SUPERVISOR board is the same for
non-redundant and redundant networks.
4.1.3 PC UNIT WITH 53WS5000 PRODUCT PACKAGE INSTALLED
The 53WS5000 product package can be ordered with MicroLink communications capabilities to be
installed into a PC unit that is an IBM AT-compatible PC (see IB 53WS5000, Section 2, for mini-
mum PC configuration). As with the SUPERVISOR-PC unit, it is possible to have one standard
Datalink SUPERVISOR board (p/n 686B574) and one MicroLink SUPERVISOR board (p/n
686B619), or two MicroLink SUPERVISOR boards, in the same PC unit. The SUPERVISOR board
can be installed in any full length slot of an IBM AT-compatible PC as described in IB 53WS5000,
sub-section 2.3.1.1. If the PC unit is installed on a redundant network, then the redundant Mi-
croLink card must be installed in the slot immediately to the right of the MicroLink SUPERVISOR
board. Installation of the MicroLink SUPERVISOR board is the same for non-redundant and redun-
dant networks.
4.2 CABLING
A detailed illustration of MicroLink network cabling is provided as Figure 4-1. Note that the SUPER-
VISOR board and the SUPERVISOR redundant MicroLink card each have only a single modular
connector for MicroLink attachment. Therefore, a Communications Interface Terminal Board is
needed to provide two connections when the network is arrayed in a T-Configuration as illustrated
in Figure 4-2. Figure 4-2 shows the drop cable (T-stem) coming from the ITB to the PC. (The drop
cable should be as short as possible, preferably less than five feet [1.5 meters].) Network cables
interconnect network nodes to the left and to the right of the Communications ITB (T-bar). Also, at
each physical end of the network, a Communications ITB is installed as a terminator. The termina-
tion resistors installed on the Communications ITB are designed for 12 or more nodes on the net-
work. If one to three nodes are installed, the standard 100 ohm terminating resistor should be
removed and replaced with a 910 ohm resistor (p/n 161K228U24). If the network has four through
eleven nodes, the standard 100 ohm terminating resistor should be removed and replaced with a
470 ohm resistor (p/n 161K228U17). The resistors should be changed in both terminators and
should be connected between terminals 3 and 4 of TB1 on the Communications ITB. If the Commu-
nications ITB is to be used for interconnection instead of termination, the resistors should be re-
moved.
Section 4. MicroLink Installation
12