Introduction; Signal Conditioning Module; Signal Conversion Module; Display Module - EIT MULTIBRITE MB100AC1 Operator's Manual

INTRODUCTION

1.
The MultiBrite System is presented to fill the need for monitoring several UV light sources for the purpose
of relaying a single alarm to an operator when any of the sources falls below the specified limit.
A MultiBrite System is comprised of three major components, the Signal Conditioning Module, the Signal
Conversion Module, and the Display Module, each of which will be described below.

Signal Conditioning Module

1.1
The Signal Conditioning Module accepts up to 4 signals from 4 different UV sensors. Current signals from
the sensors are individually converted to a voltage level that is supplied to the Signal Conversion Module
and to the Display Module. One of the 4 signals is selected by the signal selection switch to be presented to
the display. The display continuously converts the analog voltage signal to a two digit decimal number that
represents the percentage of lamp output relative to the initial calibration level. In addition to the 4 lamp
readings, a low limit signal may be selected for display. This parameter is normally monitored while
adjusting the low limit threshold from the front panel. The adjusted low threshold is used by the level
comparators to determine if the output of any of the 4 lamps has fallen below the allowable light intensity
level.
Four individual analog voltage level outputs are provided by the Signal Conditioning Module as inputs to the

Signal Conversion Module.

Signal Conversion Module
1.2
Analog signals from the Signal Conditioning Module are directed to three possible monitoring sections,
alarm monitor, analog voltage, and analog current.
The signal from the Signal Conditioning Module is converted to a voltage output from 0 to 10 volts on the
signal conversion module. This output DC voltage is proportional to the signal from the Signal Conditioning
Module. The resulting analog voltage output is capable of driving up to a 2 milliamp load at 10 volts.
The converted analog voltage output signal is further converted into a 4 to 20 milliamp signal capable of
supplying current into a maximum load of 250 ohm. The 4 to 20 ma signal is proportional to the applied
input voltage and, consequently, to the measured light intensity.

Display Module

1.3
Each of the four analog signals are routed into one of the 4 individual comparators. Each signal is compared
to the adjusted threshold level that is common to all four comparators. Whenever a signal falls below the
selected threshold, an alarm output connection is made indicating an alarm condition. In addition to the
remote indication provided, a local audible alarm will sound. An alarm silence switch allows the user to
silence the internal audible alarm. An alarm LED will continue to indicate the alarm condition even though
the audible alarm on the Display Module has been silenced.

Alarm Outputs

1.4
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MultiBrite Operator's Manual
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