Omni-beam sensor heads, Sense and load led indicators, Measuring excess gain – Banner OMNI-BEAM Series User Manual

Page 6

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OMNI-BEAM Sensor Heads

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6

Sense and Load LED Indicators

The Sense LED indicates when a target has been sensed. When the sensor head is
programmed for Light Operate, it lights when the received light signal exceeds the #5
threshold. When programmed for Dark Operate, it lights when the received light
signal falls below the #5 threshold. See figure 7.

The Load indicator LED lights whenever the output is energized (after the timing
function, if applicable).

Measuring Excess Gain

OMNI-BEAM’s D.A.T.A. indicator display may be used to measure the excess gain and
contrast during sensing, installation, or maintenance.

Excess gain is a measurement of the amount of light energy falling on a photoelectric
sensor’s receiver, over and above the minimum amount needed to operate the
sensor’s amplifier. Excess gain is expressed as a ratio:

Excess gain (E.G.) = light energy falling on receiver

amplifier threshold

The amplifier threshold is the point at which the sensor’s output switches
(corresponding to the #5 level of the D.A.T.A. display). When LEDs #1 through #5 are
ON, the excess gain of the received light signal is equal to “1x.” The chart below
shows how excess gain relates to the D.A.T.A. light array indication.

Figure 7. Sense and Load indicators

Relationship Between Excess Gain and D.A.T.A System Lights

D.A.T.A. Light

LED Number

STANDARD

Scale Factor

FINE*

Scale Factor

#1
#2
#3
#4
#5
#6
#7
#8
#9

#10

0.25x

Excess Gain

0.35x

Excess Gain

0.5x

Excess Gain

0.7x

Excess Gain

1.0x

Excess Gain

1.3x

Excess Gain

1.7x

Excess Gain

2.2x

Excess Gain

2.9x

Excess Gain

3.7x

Excess Gain

(or more)

0.5x

Excess Gain

0.7x

Excess Gain

0.8x

Excess Gain

0.9x

Excess Gain

1.0x

Excess Gain

1.1x

Excess Gain

1.2x

Excess Gain

1.3x

Excess Gain

1.7x

Excess Gain

2.2x

Excess Gain

(or more)

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