Crown MRX-12S Quick Reference Manual

* System
@crown
®
MRX-12

Overview

™
The MRX-12 is a computerized relay patch
bay system. It also is available in a slave ver-
sion ( MRX-12S ). Operating under IQ control,
both versions have twelve 1x1 SPST relays
for switching electrical signals. The MRX-12/
12S is ideal for routing unbalanced audio from
line level to high powered speaker level, AC
or DC power, digital signal routing and switch-
ing, and other electrical signals. Each relay
can handle at least 6 amperes at 240V. Pic-
tured to the right are the front panels of an
MRX-12 and an MRX-12S . Simple descrip-
tions follow that introduce each feature of the
unit, and provide brief overview of operation
and basic electrical specifications.

Masters and Slaves

In terms of practical operation, the slave ver-
sion is almost identical to the master version.
A slave utilizes the microprocessor of its
master to operate its own relays. Up to 31
slaves may be operated from any one mas-
™
ter, including MRX-24 master units ( MRX-
24 is another Matrixer model with a different
relay configuration). Without its own proces-
sor, slave unit Aux ports are inoperative and
it has no battery backup. Slaves communi-
cate with their master via special slave bus,
and the addressing of masters and slaves is
handled differently. By using the processing
power of a master unit, using slaves in larger
B
MRX-12/12S MODULE CIRCUIT BOARD
®
Quick Reference
™
/12S MATRIXERS
Matrixer systems is highly cost effec-
tive.

IQ-CAG Card Cage Installation

All IQ Matrixer units are designed for
easy installation into a Card Cage. The
IQ-CAG is a four rack space cage
which can hold about 6 MRX modules
plus an IQ-LPS +12 VDC Linear Power
Supply. Matrixers require +12 VDC. If
an IQ-LPS is not used, another supply
such as an adaptor or battery is re-
quired. Components designed to mount
in the IQ-CAG are modular in construc-
tion. They slide into the cage on rails,
and are held in place by small screws.
At the rear of the cage "T-board" is used
to provide connection to relays, and for
Digital Communication. The T-board for
MRX-12/12S units is shown on the fol-
lowing page.

Front Panels

Front panels for both versions are
shown to the right. On each is a power
indicator showing that the unit is pow-
ered by +12 VDC. A DSPI indicator also
lights up to indicate that digital information
addressed to that unit is being received.
When power is removed an internal battery
will maintain programming memory in a mas-
ter unit for at least 60 days.
A
MRX – 12
DSPI
POWER
1718 W. Mishawaka Rd.
Elkhart, IN 46517 U.S.A.
MRX-12 (MASTER) & MRX-12S (SLAVE)

A. Relays

MRX-12/12S relays are SPST devices which
can handle 25 Amperes at 250V, and are ar-
ranged as a bank of 12 1x1 relays. By tying
relays together at the T-board, any ma
F E C
MRX – 12
DSPI
POWER
1718 W. Mishawaka Rd.
Elkhart, IN 46517 U.S.A.
D