Specifications

Installation
VTM-200 Installation and Operation Handbook 2-2
COM Port Electrical Interface Selection
CAUTION — these instructions are for use by qualified personnel only. To reduce
the risk of electric shock, do not perform this installation or any servicing unless you
are qualified to do so. Refer all servicing to qualified service personnel.
The COM interface on the VTM-200 as well as the Remote Control Unit (RCU-200)
normally uses an EIA-232 electrical interface for communications. Both the RCU and
the VTM units are capable of utilizing an alternate cable interface, RS-422, which
permits longer inter-unit cabling distances. In order to support an RS-422 connection
the internal jumpers must be reconfigured. See Interface Mode Jumper Configurations
for more details.
Interface Mode Jumper Configurations
In order to utilize the RS-422 interface, internal jumpers in both the VTM and RCU
units must be repositioned. Table 2-1 details the jumper configuration for the
VTM-200 (for more information on the RCU-200, See Appendix D, “Remote Control
Unit (RCU-200)”). All signal and power cabling should be removed from the units
before disassembly.
The jumpers on the VTM-200 are located near the back connector area of the VTM204
board. In a VTM-200 with an audio option board installed, the jumpers would be
located under the audio option board, which must be temporarily removed in order to
reconfigure the jumpers.
Table 2-1. Jumper Configuration for RS-422 Interface
Connection Jumper CN1 Jumper CN3 Jumper CN5
EIA-232
Connect 1-2 No connection No connection
RS-422
No connection Connect 1-2 Connect 1-2