picture ISM-1230


  • 1-channel light barrier amplifier for dust and turbidity measurement
  • 4 operation modes
  • 2 frequencies
  • Sensor control
  • Test and diagnostic function
  • Analog output 0-10 V
  • Alarm output
  • Test input

Product Description

The ISM-1230 is a special amplifier for optical turbidity measurement resp. dust measurement.

An infrared transmitter and a receiver (sensor heads) is to be connected to the amplifier. The light beam passes the supervised medium. This system operates with modulated infrared light. The transmit power is adjusted automatically for a constant input signal at the receiver.

Four measurement ranges resp. measurement modes are available:

Mode 1

100% of the overall range correspond to 0-10 V at the analog output. With an offset the 0V threshold can be moved.

Mode 2

50% of the overall range correspond to 0-10 V. The measurement range is stretched twice. By the offset, the starting point of the measurement range is fixed to e.g. 20% of transmit power, to even out pollution of the sensor heads. Below 20% the voltage level is 0V, between 20% and 70% the voltage is 0-10 V (corresponding to 50% of the overall measurement range). Above 70% the voltage is always 10 V.

Mode 3

25% of the overall range correspond to 0-10 V. The measurement range is stretched fourfold.

Mode 4

12,5% of the overall range correspond to 0-10 V. The measurement range is stretched eightfold. In this mode a little change of turbidity achieves the highest change of the output voltage.

The offset is setted by pressing the switch at the front of the device. Alternativly, a setting by the test input is possible.

The recent value of turbidity is available at the analog output (0-10V). Additionally, the switching output acts if the voltage level exceeds the adjusted level of the potentiometer (0-10).

Like this, a simple fan control can be implemented. The switching output is deactivated if the voltage falls below the adjusted threshold with a hysteresis of approx. 0,2 V.

Technical Specifications

Number of channels


Range (with transmitter ITL and receiver IRL / IRH)

7 m / 15 m

Range (with transmitter ITH and receiver IRL / IRH)

10 m / 25 m

Range (with transmitter ITA and receiver IRL / IRH)

20 m / 55 m

Operation modes


Transmit frequencies

3,7 / 4,3 kHz

Switching output

60 V AC / DC short-circuit proof

Reaction time


Alarm output

PNP 24 V, 100 mA

Error output


Analog output

0...10 V

Test input

24 V DC

Housing material


Protection class

IP 20

Dimensions B x H x T

35,8 x 95 x 58 mm

Supply voltage

24 V DC

Current consumption

2,4 W

Ordering Information


Order code

Plug Connection



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Manual ISM-1230

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Datasheet ISM-1200 English
For technical data, connection diagrams, installation instructions and safety instructions please refer to the Datasheet ISM-1200

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Operating instructions multilingual