SM500A—Automatic Switching System
Black Box Corporation
8
990-000-0001-E8
1 General Description
1.1 Introduction
The Automatic Switching System SM500A provides an efficient, reliable means of switching
different interfaces between “active” and “fallback” positions.
The SM500A can perform switching at the channel, chassis, or system level. At the system
level, up to 64 chassis can be ganged together. Each chassis accommodates one Power
Supply/Control Card or Advanced Control Card and up to 16 Switching Interface Cards with
up to 32 switching channels, for a system maximum of 2048 switching channels.
Switching Interface Cards are transparent to all communication formats and speeds. For
switching, they use magnetic latching relays, which remain in the last switched position in the
event of power loss. A wide variety of Switching Interface Cards—RS-232/V.24, EIA-530,
Coax, RJ-11, RJ-45, V.35, and others—can be mixed within the same chassis, affording
maximum flexibility to the user.
For additional reliability, two Power Modules (SM514-A-PS or SM514-A-PS-E) per chassis
or an AC Redundant Power Supply (SM535A) may be used with the Automatic Switching
System SM500A. The SM500A also has options to operate with -48VDC.
1.2 User Interfaces
This documentation describes five types of control for the SM500A Automatic Switching
System—control via manual switching, SNMP protocol, ASCII commands, Web browser and
GUI based software. For manual control, the following Power Supply/Control Cards may be
used: SM531 C (12VAC) or SM532 C (-48VDC). For SNMP, ASCII, Web browser or GUI
based software, the following Advanced Control Cards may be used: SM533 C (12VAC) or
SM534 C (-48VDC).
1.3 System Switching Functions
The Automatic Switching System SM500A provides the following switching functions:
Individual card switching
—this function applies only to a single channel and is triggered by
the toggle switch located on the front of the corresponding Switching Interface Card. For
cards with double channels, two toggle switches (one per channel) are available. The two
toggle switches may be connected in parallel (via jumper selection) to perform simultaneous
switching of the two channels, if required. The switching is enabled/disabled by turning the
key-activated switch on the chassis front panel.
Group gang switching—
this function applies to a selected group of Switching Interface
Cards that simultaneously switch within one chassis. The group is defined by assigning a
number (via jumper selection) to each card in the group. Up to four groups may be defined.
Switching of the group is performed by any one of the toggle switches of the cards that
belong to the group. The switching is enabled/disabled by turning the key-activated switch on
the chassis front panel.
Chassis gang switching
— this function simultaneously switches all Switching Interface
Cards within one chassis. It is performed by toggling the GANG switch located on the chassis
front panel. GANG switching is enabled/disabled by turning the key-activated switch on the
chassis front panel.
