Variable Bright/Dim Lighting Controller
MSM295C
Product Description
The MSM295C is a two-channel variable bright/dim lighting
controller. The controller is designed to turn ON/OFF and vary the
intensity of lamps used in reading, table, or other lighting
situations. The two-channel design allows control of two lamps
from a single MSM295C. The unit uses a pulse width modulator
circuit for power efficiency. The controller has Master ON/OFF,
bright, and dim functions that override the individual control inputs.
Technical Specifications
Electrical
Power, Internal
Circuitry
2.5 A max at +28 VDC
100 mA Idle Current
Max Current
Ratings
1 A each CKT1 & CKT2
2 A both channels driven
Switch Contact In
< 1 VDC, Momentary
Ground
Features
Input Timing
The following list provides an overview of features for the
MSM295C:
Status Out LED
G
G
G
G
Dual circuits in one unit for control of two lamps
ON/OFF and variable lighting from DIM to BRIGHT functions
Single input control for each circuit
Output to light the status annunciator LED in a switch panel
when lamp is ON
G Master circuit overrides both individual circuits
G Lightweight, compact size
G Solid state circuitry
Mom. Gnd. < 250 mS =
ON/OFF
Cont. Gnd. > 250 mS =
Variable DIM to BRIGHT
Ground, 100 mA Max. Sink
Variable Output
0 to +28 VDC
Master Inputs
< 1 VDC, Momentary
ground required
Mechanical
Dimensions
5.0”L x 5.0”W x 1.0”H
Mating Connector
DBMA-25S
Weight
7.2 ounces / 201.6 grams
Application Notes
1.
2.
3.
4.
The MSM295C is designed with two independent circuits
(CKT1 and CKT2) for the control of ON/OFF, BRIGHT, and
DIM lighting functions. A master circuit controls both of the
independent circuits.
The controller powers up in the ON position and DIM state.
This configuration cannot be altered.
From the DIM state, applying a momentary ground input
greater than 250 mS on the switch contact varies the output
towards +28V, causing the lamp intensity to brighten.
Release the momentary ground input when the lamp is at the
desired brightness. The next momentary ground input less
than 250 mS turns the unit OFF. If the desired setting is
missed, the lamp must be turned OFF and ON to reset the
circuit.
The Master has 4 inputs to control CKT1 and CKT2
simultaneously. The Master SET input turns all lights
connected to this module to the ON and DIM state. The
Master RESET turns all lights connected to the module to the
OFF state. Both require momentary ground application. The
Master BRIGHT and DIM inputs require momentary ground
inputs to vary the intensity of both circuits.
Installation Guidelines
1.
2.
All power, input, output, and ground wires must be 22 AWG
minimum. Ground wires must be grounded within twelve
inches of the unit.
Protect power wires with circuit breakers or fuses located
close to the electrical power source bus.
Drawings
Description
530024 Rev IR1
MSM295C Specification Drawing
Document # 530117A – Revision History
Level
Date
Description
IR
7/1998
Initial Release
A
8/1999
Update features, correct power / weight
PROPRIETARY NOTICE
Despite any copyright notice, this data and information
disclosed herein contains confidential, proprietary designs owned
by Audio International, Incorporated. Neither this data nor the data
contained herein shall be reproduced, used, or disclosed to
anyone without the written authorization of Audio International, Inc.
Audio International, Inc. • 7300 Industry Drive, N Little Rock, AR 72117 • Phone 501-955-2929 / Fax 501-955-2988 / www.audiointl.com