Phoenix ILA-450 User manual

ENGLISH

Instruction manual

Phoenix Professional Audio GmbH

Gewerbepark Conradty 12

D-83059 KOLBERMOOR

Tel. 0049-(0)8031-30425-0

Fax. 0049-(0)8031-30425-25

www.phoenix-pa.com

shop.phoenix-pa.com

[email protected]

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Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

All brands are property of their respective owners.

ILA-450 Version 010814

DOC-010814

Made in EU

For systems

according to

EN 60118-4

IEC 118-4

INDUCTION LOOP AMPLIFIER (LOOP AMPLIFIER) ILA-450

Now new with „MLC“-control to correct frequency errors, COMPRESSOR, control

of the loop impedance and SPEAKON output socket.

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Instruction manual

1. Read this manual carefully.

2. Keep this manual well.

3. Consider all warnings.

4. Follow all instructions.

5. ATTENTION: to avoid ﬁres and electric shocks, this system may not be exposed to rain and humidity. Do not use

this device close to any waters.

6. Only clean it with a dry cloth.

7. Do not cover any air vents.

8. Do not put the device close to heat sources like radiators, hot air dampers, ovens or other devices (including am-

pliﬁers), which emit warmth.

9. Do not override the safety function of the inverse-polarity protection or the safety plug. A plug with inverse-polarity

protection has two pins, and one of them is wider than the other (only for USA/Canada). A safety plug has two pins and

one ground pole. When the included plug does not ﬁt into your socket, the socket is obsolete and has to be replaced

by an electrician.

10. Pass the power cable in a way, that nobody can step onto it and that it cannot be jammed. This is especially valid

for plugs, sockets and the place where the cable comes out of the device.

11. Only use products and accessories speciﬁed by Phoenix Professional Audio GmbH.

12. Let maintenance operations only be carried out by qualiﬁed maintenance staff. The device has always to be

maintained, when it has been damaged in any way, f.i. when the power cable or the mains plug is damaged, if liquids

have been spilt onto the device or objects have been fallen into it, if the device has been exposed to rain or humidity,

if it does not work normally or if it has been fallen down.

The exclamation mark in a triangle shall advise the user of the existence of important

operating- and maintenance instructions in this manual.

The symbol consisting of a ﬂash with an arrowhead in a triangle shall advise the user

of the existence of non-isolated, dangerous voltages within the housing, which can

be strong enough to give an electric shock.

ATTENTION: TO REDUCE THE RISK OF AN ELECTRIC SHOCK, DO NOT REMOVE

THE COVER. USE QUALIFIED STAFF FOR ALL MAINTENANCE OPERATIONS.

Important safety precautions and symbol explanation

EXPLANATION OF THE GRAPHIC SYMBOLS

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

All brands are property of their respective owners.

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Instruction manual

GENERAL

The new redesigned ILA-450 is a loop ampliﬁer as professional solution for the installation to loop ampliﬁers.

The ILA-450 loop ampliﬁer for audio transmission is used extensively to supply hearing devices by inductive

audio signals.

The ILA-450 Phoenix induction loop ampliﬁer has been developed as a high quality LOOP-ampliﬁer for

medium induction loops.

The system is characterized particularly easy installation, customer-oriented operation and easy use of the

device at optimum performance.

Induction loop ampliﬁers are very often used in churches, cinemas, theaters, sales agencies, counters,

interpreter systems or DRIVE IN / DRIVE-THROUGH, so that hearing aid users under difﬁcult acoustic

conditions (background noises, reverberation etc.) can hear much better without disturbing noises.

Advantages of the system:

By the inductive coupling of hearing devices the wanted signal (audio transmission) can be heard much

better without disturbing noises. By the transmission of an audio signal via the induction loop an acceptable

wanted signal/interference signal ratio is reached.

Useful information:

A purely acoustic, direct sound transmission (between speaker and hearing device) by reverberation and

background noises signiﬁcantly deteriorates the perception of the wanted signal by the hearing device wearer.

Receiver ILA-E:

With the induction loop receiver ILA-E a loop system can be checked or maintained easily, fast and uncom-

plicated.

The device is especially suitable for responsible staff wherever the induction transmission is installed, or for

people who need a high quality „wireless“ hearing device without hearing aid, f.i. with channel interpreter

systems.

Planning of the loop design:

Not in every place where it would be desirable, acceptable resp. good conditions for installing the induction

loop can be found. Therefore in the planning phase it is necessary to examine a suggested place regarding

the following conditions:

- The magnetic interference ﬁelds of electric systems, f.i. heating systems in the ﬂoor or the roof area and

the electronic controls of lighting systems (particularly in cinemas, theaters etc.)

- The inﬂuence of magnetical or electrically conducting materials in the building structure, particularly in the

place where the loop shall be installed.

- The presence of further induction loops in the neighbourhood, which signals could interfere the planned

loops.

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

All brands are property of their respective owners.

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Instruction manual

GENERAL

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

All brands are property of their respective owners.

Unfortunately it is still common practise to assemble the 100 V power ampliﬁers with the additional audio

transformer.

Such systems are generally inaccurate as they show a disadvantageous frequency response. Such a system

conﬁguration can increase the inductance with increasing frequency, so the high frequencies which are

important for the speech intelligibility cannot be radiated anymore.

Induction loop ampliﬁers do not have this disadvantage, therefore they are ideal to produce a constant ﬁeld

strength by the use of dynamics processors and a special ampliﬁer technology (constant current source).

Control

All important functions of the induction loop ampliﬁer are controlled.

That means the ILA-450 induction loop ampliﬁer controls its internal power ampliﬁer, the functional efﬁci-

ency of the connected induction loop with a pilot-tone pulse. Should a controlled function fail, the yellow

LED at the front side of the induction loop ampliﬁer does not light and the fault contact „INFO LOOP OK“

[15VDC] will be currentless.

Compatibility according to EN 60118-4:

The most important feature with the redesign was the system compatibility to the standard EN 60118-4, so

a loop assembly based upon a „LOOP-SEGMENT“ system is possible.

In a „LOOP-SEGMENT“ system always two ILA-450 which form a magnetic ﬁeld work together, thereby

on the entire area always a constant ﬁeld strength of the magnetic ﬁeld is reached.

The magnetic ﬁeld outside the intended area quickly loses strength and drops to ZERO. This is done by

coupling a phase shift FS-1 which is connected between both ILA-450, which in turn produces a signal

phase difference of 90 degrees in the electric current by two adjoining induction loops.

Further instructions for loop installation by using a phase shifter FS-1 are described detailed in the further

chapter.



Instruction manual

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

All brands are property of their respective owners.

Before starting the ampliﬁer ILA-450 we ask you to read the safety instructions carefully.

We ask you to carry out the installation according to the following guidelines:

In a clearly visible position a sign „INDUCTIVE COUPLING“ should be placed near the entrance to

the area where an induction loop is installed.

1 - Always put the ampliﬁer onto a smooth and stable surface.

2 - Choose dry surroundings and do not put any liquids onto the ampliﬁer.

3 - Avoid the proximity to heat sources.

4 - Never open the ampliﬁer´s housing without pulling the mains plug out of the socket before.

5 - Only connect the device to 230 VAC mains voltage.

SAFETY INSTRUCTIONS

- Cooling element with a temperature-controlled fan control (internal)

- Short circuit protection - abnormal temperature protection - open circuit protection - overload protection

- LED level display „compressor“

- LED level display „output level“

- LED display loop detector „ERROR“

- LED display system monitoring „PROTECT“

- LED display „system POWER ON“

- SOFT START

- Balanced microphone/line inputs

- INSERT PORT in-/output

- SPEAKON connection for LOOP line

- Phönix connection for LOOP CONTROL

- Separate volume control for all inputs

- Countersunk volume controls, LF/HF-EQ controls

- MLC control at the front side ( „METAL LOSS CORRECTION“)

- Compression LED display 0 to 18 dB

- Output level LED display -12 to 0 dB

- Phantom power for inputs MIC.-1 and MIC.-2 and shiftable phantom power for input MIC./LINE3

- 19“ brackets can be demounted for table version

- Space saving 1 U housing version

- Monitoring of the loop impedance in the range from 0.5 Ohm to 3.0 Ohm

MAIN FEATURES

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Instruction manual

FRONT SIDE

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1 2 3 4

5 6

9 10

1.- MIC.-1

This control determines the sensitivity of the „MIC-1“ input.

2.- MIC.-2

This control determines the sensitivity of the „MIC-2“ input.

3.- MIC.-3/LINE

This control determines the sensitivity of the „MIC.-LINE-3“ input.

4.- COMPRESSOR

LED display (0 dB to 18 dB)

5.- LOW-EQ Filter (+-12dB)

Separate LF-control of the particular microphone- resp. LINE inputs.

Please select the DIP switch for input 3 between MIC.- and LINE sensitivity at the rear side.

6.- HIGH-EQ Filter (+-12dB)

Separate LF-control of the particular microphone- resp. LINE inputs.

Please select the DIP switch for input 3 between MIC.- and LINE sensitivity at the rear side.

7.- MASTER

With this control the electrical current ﬂow of the loop can be adjusted.

8.- MLC-„METAL LOSS CORRECTION“

Control to correct frequency response errors which are caused by metals close to the induction loop.

Useful information:

Turn the MLC-control to reach the best tone (audio signal) on the induction loop, simultaneously listen to

the audio signal with ILA-E receiver via the headphones.

Repeat the measurement process for all induction loop ampliﬁers resp. induction loops ILA-450 which

are bound in the system.

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Instruction manual

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

All brands are property of their respective owners.

FRONT SIDE

1 2 3 4

5 6

9 10

9.- OUTPUT LEVEL

Output level LED display (-12 dB bis 0 dB) shows the current MASTER output level.

10.- PROTECT LOOP OK POWER

System fault indication with red LED.

When the PROTECT control display lights without input signal, possibly there are system oscillations or

other disturbances (f.i. the ampliﬁer´s temperature is too high).

Disconnect the load and reduce the ampliﬁcation to zero. If the LED continues to light, possibly the ampliﬁer

has to be maintained.

IMPORTANT:

At system FAULT (PROTECT-LED lights) no output level and LOOP OK is displayed!

LOOP OK

Fault indication for loop impedance; should the LED light, the impedance of the induction loop is not within

the measuring range of 0.5 -4.0 Ohm).

IMPORTANT:

After elimination of the fault please always reset the loop ampliﬁer ILA-450 by switching the ampliﬁer off

with the POWER button, wait for 3 seconds and switch it on again with the POWER button.

POWER operation display.

LED lights, LOOP ampliﬁer ILA-450 is activated.

11.- ON/OFF mains switch

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Instruction manual

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

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REAR SIDE/CONNECTIONS

1 2 3 4 5 6 7 8 9 10

1.- MAINS INPUT TERMINAL 230VAC/50-60 Hz

230VAC mains input terminal. Connect the ILA-450 with the power cable to the network.

2.- LOOP CABLE

SPEAKON bush 2-poled, the loop line shall be connected with the clamps (+ Pin) and (- Pin).

3.- LINE OUTPUT [LINE-OUT]

Balanced audio signal output to JACK bush (max. 0 dB).

4.- INSERT

The INSERT bush is unbalanced connected and is used to connect external signal processing equipments

like f.i. additional EQ´s. When the plug is not inserted resp. no additional device is connected with INSERT,

the signal path is interconnected 1 to 1.

5.- AMLIFIER/LOOP CONTROL

Fault indicator output 15VDC, the contact remains isolated when the ampliﬁer and the induction loop work

failure-free. The contact is supplied with 15VDC voltage as long as a system failure or loop failure is present.

6.- DC OUTPUT (+15VDC/-15VDC)

Balanced output voltage +/-15VDC, is used to connect a phase shifter FS-1.

7.- PHANTOM POWER/MIC.-LINE SWITCH

MODE-SWITCH PHANTOM. DIP- (ON) the input MIC.-/LINE 3 is supplied with 12VDC phantom power for

condenser microphones, DIP- (OFF) phantom power is deactivated.

MODE-SWITCH MIC.-LINE. With this switch you determine the sensitivity of the input MIC.-/LINE 3,

switchable between microphone level -50 dB and the line level -10 dB.

Useful information:

Always adjust the correct input sensitivity, otherwise instead of automated system a too high signal

level is reached at the input (position to MIC. and input signal with LINE level), so that the ampliﬁer

cannot process the signal correctly and the signal can be reproduced distorted at the loop output.

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Instruction manual

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

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REAR SIDE/CONNECTORS

1 2 3 4 5 6 7 8 9 10

8.- MIC.-/LINE 3 INPUT

The input is designed balanced (+2), (-3), (1-shielding).

The input sensitivity is adjusted at the device´s front side with separate control MIC.-/LINE 3 and adjusted

by the MODE-SWITCH No. 7.

9.- MIC.2 INPUT

The input is designed balanced +2, -3, 1-shielding. The input sensitivity of the input 2 is adjusted at the

device´s front side with separate control MIC. 2.

10.- MIC.1 INPUT

The input is designed balanced +2, -3, 1-shielding. The input sensitivity of the input 1 is adjusted at the

device´s front side with separate control MIC.1.

Useful information:

Unbalanced inputs: strip the insulation of the wire liners for

6 mm and connect them as shown with the clamps. The pin

in the middle has to be connected with the screen pin as

shown. Tighten the screws ﬁrmly.

1 GND

2 +IN

3 -IN

1 GND and wire link to 3

2 +IN

Balanced inputs: strip the insulation of the wire liners

for 6 mm and connect them as shown with the clamps.

Tighten the screws ﬁrmly.



Instruction manual

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

All brands are property of their respective owners.

TECHNICAL APPENDIX

To supply a perfect sound signal also to the users of hearing devices, so-called induction loops are installed.

Herewith the signal is transmitted inductively by a loop passed in the middle of the room into a receiver coil

which is located in the hearing device.

The induction loop has to be passed in a way that it encloses the intended area. The impedance of the loop

is approximately equal to the DC resistance.

When installing the loop into concrete, protective PVC pipe has to be used, IN NO CASE STEEL PIPE.

With difﬁcult structural conditions prior to that a test loop has to be constructed and the supply has to be

checked.

INDICATION:

Directly above the loop wires the reception is worst, as there the ﬂux lines run horizontally.

Cable cross-section

Cable min. length Cable max. length

0.5 mm

15 meter 90 meter

1.0 mm

30 meter 130 meter

1.5 mm

42 meter 160 meter

2.5 mm

71 meter 180 meter

4.0 mm

115 meter 190 meter

CONSTRUCTION SIMPLE LOOP SYSTEM

A simple induction loop system consists of a LOOP ampliﬁer ILA-450 and one or more induction loops of

the same size, see drawing.

ILA-450 LOOP- AMP

Drawing 1.1 shows single loop Drawing 1.2 shows double loop

10.

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Instruction manual

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11.

Please pass parallel lines close together

A much better result (constant ﬁeld strength) than with single loops is achieved by installing „LOOP-

SEGMENT“ loops. The individual segments have to be of the same size, the distances should be between

2 meters and 5 meters. Examples of use: row of seats in theaters, churchs, schools etc.

IMPORTANT:

Disadvantage of the LOOP-SEGMENT loop without phase shifter is:

Wherever two loop lines run parallel, the ﬁeld strength is „0“! The area of the „0“-ﬁeld strength can be

between some centimeters up to one meter.

IMPORTANT:

Rooms and areas where an induction loop is installed, should be marked accordingly.

CONSTRUCTION SIMPLE LOOP SYSTEM

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Instruction manual

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12.

The example shows an induction loop with limitation of the induction ﬁeld to the side room.

The additional limitation loop is mainly suitable for applications, where a partitioning has been carried out

by f.i. sheetrocks, where two independent variable loops with different audible signals shall be processed.

The length of the limitation loop´s additional winding shall be in the ratio approx. 1:11.

Indications refer to a square room!

IMPORTANT:

Rooms and areas where an induction loop is installed, should be marked accordingly.

LOOP SYSTEM WITH EXTINCTION OF THE MAGNETIC FIELD

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Instruction manual

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All brands are property of their respective owners.

13.

The best result (constant ﬁeld strength) is reached by installation of „DOUBLE LOOP SEGMENT“ with phase

shift. Compatibility according to EN 60118-4.

Such double LOOP SEGMENT induction loops are advisable for large areas and at high inﬂuence to the

induction ﬁeld by metallic objects located in concrete (walls and ﬂoors).

Examples of use: big churches, exhibition halls, stations, schools etc.

As the installation of the double LOOP-SEGMENT induction loop takes a lot of time and effort, this kind

of induction loops is usually only possible for new constructions or general refurbishment of the buildings.

Advantage of the double LOOP-SEGMENT induction loop is the up to 4-fold lower loss of the induction

ﬁeld (low power - large area).

For double LOOP-SEGMENT induction loops the audio signal is connected to the ﬁrst ILA-450 LOOP

ampliﬁer, which in turn supplies the ﬁrst loop in the system.

By the phase modulation the audio signal is shifted by 90

phases and routed to the second ILA-450, then

the second ILA-450 has to supply the second parallel induction loop in the complete system.

All LOOP segments should have the same size and should not excess areas of 2 up to 5 meters.

Compatibility according to EN 60118-4

In a „LOOP-SEGMENT“ system always two ILA-450 work together, they form a magnetic ﬁeld, thus on the

complete area always a constant ﬁeld strength of the magnetic ﬁeld is reached.

The magnetic ﬁeld outside the intended area loses quite rapidly strength and drops to ZERO. This is done

by coupling a phase shifter FS-1 which is switched between the two ILA-450, this again produces a signal

phase difference of 90 degrees in the electrical ﬂow by two adjoining induction loops.

LOOP SYSTEM WITH 90 DEGREES PHASE SHIFT according to EN 60118-4

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Instruction manual

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14.

LOOP SYSTEM WITH 90 DEGREES PHASE SHIFT according to EN 60118-4

Example for a simple LOOP-SEGMENT induction loop system with two ILA-450 (MASTER/SLAVE) and

FS-1 90 degrees phase shifter. It is important that the induction loops are approximately of the same size.

ILA-450 LOOP- AMP

MASTER 0

SLAVE 90

System with single loops

System with several loops „COMB SYSTEM“

ILA-450 LOOP- AMP

MASTER 0

SLAVE 90

MASTER 0

SLAVE 90

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Instruction manual

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All brands are property of their respective owners.

15.

LOOP SYSTEM WITH 90 DEGREES PHASE SHIFT according to EN 60118-4

Example for a multiple LOOP-SEGMENT induction loop system with (MASTER/SLAVE) conﬁguration, to

cover very large areas with constant magnetic ﬁeld strength.

Important information:

It is important that the induction loops MASTER and SLAVE are approximately of the same size and have

a width of approx. 50 - 66 % of the loop length.

System component:

4 x ILA-450 induction loop ampliﬁer

1 x FS-1 90

phase shifter

ILA-450 LOOP- AMP

MASTER 0

SLAVE 90

MASTER 0

IMPORTANT:

Rooms and areas where an induction loop is installed, should be marked accordingly.



Instruction manual

Phoenix logo is registered at the German Patent- and Trademark Ofﬁce (TM)

All brands are property of their respective owners.

16.

LOOP SYSTEM WITH 90 DEGREES PHASE SHIFT according to EN 60118-4

By the phase modulation the audio signal is shifted by 90

phases and transmitted to the second ILA-450

resp. to the second induction loop.

Then the second ILA-450 has to supply the second parallel induction loop in the complete inductive hearing

device system.

The ﬁrst LOOP ampliﬁer of the complete circle loop system works without phase shift with 0

The ﬁrst ILA-450 supplies the ﬁrst parallel induction loop in the complete inductive hearing system.

In a „LOOP-SEGMENT“ system always two ILA-450 work together which form a magnetic ﬁeld, thus on

the complete area always a constant ﬁeld strength of the magnetic ﬁeld is reached.

The magnetic ﬁeld outside the intended area loses quite rapidly strength and drops to ZERO.

This is done by coupling a phase shifter FS-1 which is switched between the two ILA-450, this again effects

a signal phase difference of 90 degrees in the electrical ﬂow by two adjoining induction loops.

LOOP 0

LOOP 90

ILA-450

MASTER

ILA-450

SLAVE

FS-1

PHASE SHIFTER

INPUT

+/-15VDC

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Instruction manual

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17.

LOOP SYSTEM WITH 90 DEGREES PHASE SHIFT according to EN 60118-4

FS-1 mains side FS-1 input side

INPUT SIGNAL

MASTER 0

SLAVE 90

OUTPUT „B“

OUTPUT „A“

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Instruction manual

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18.

MATHEMATICAL CALCULATION OF THE INDUCTION LOOPS

Calculation of the induction loop type: double LOOP SEGMENT.

1.- First the room length is set (deducting 10-20 cm of the complete length for other installations).

2.- Please set the preferred segment width (between 2 meters and 5 meters depending on the ﬁeld loss).

3.- Now the coefﬁcient „X“ can be calculated.

„L“= room length

„S“= preferred segment width

From the chart, column „G“ please take the number which is closest to the calculated value „X“.

The coefﬁcient values P 1 and P 2 indicate the number of segments for both loops.

Calculation of the segment width „A“

„L“= room length

„G“= number closest to the calculated value „X“

Calculation of the distance between two segments „B“

Calculation of the shif between the two loops „C“

1,6

2.6

3.4

4.2

5.0

5.8

6.6

7.4

8.2

9.0

9.8

10.6

11.4

12.2

13.0

13.8

14.6

15.4

16.2

17.0

G P 1 P 2

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19.

Calculation example:

Room with the dimensions 25 meter x 8.0 meter, the preferred segment width is set to 3.0 meter.

„X“ shall be calculated:

From the chart, column „G“ we take a value of 8,2

The coefﬁcient values P 1 and P 2 show:

P 1 =5

P 2 =5

„A“ shall be calculated:

Now the exact distance at the beginning of the two loop segments „B“/ „A“ shall be calculated:

Calculation of the shift between the two loops „C“

8,3

8,2

3,05

(meter)

1,6

3,05

4,88 (meter)

4,88

2,44

(meter)

2.6

3.4

4.2

5.0

5.8

6.6

7.4

8.2

9.0

9.8

10.6

11.4

12.2

13.0

13.8

14.6

15.4

16.2

17.0

G P 1 P 2

MATHEMATICAL CALCULATION OF THE INDUCTION LOOPS

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Instruction manual

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20.

The drawings show the installation of the two calculated induction loops of the calculation example.

Induction loop No. 1 (the ﬁrst ILA-450)

Induction loop No. 2 (the second ILA-450)

Induction loop „complete“ (the ﬁrst ILA-450 and the second ILA-450 LOOP ampliﬁer in the system)

MATHEMATICAL CALCULATION OF THE INDUCTION LOOPS

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