Tmdoc0328d Eng

1Data sheet Zener barriers

Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in GermanyPepperl+Fuchs Group Tel.: Germany +49 621 776-0 USA +1 330 4253555 Singapore +65 67799091 Internet http://www.pepperl-fuchs.com

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Type Nominal data Intrinsically safe characteristics for [EEx ia] IIC Certification no.

+ ve - ve a.c. V Uz (V) Rmin () IK(mA) Pmax(W) Cmax (F) Lmax (mH) L/R RatioZ 705

Z 710

Z 805

Z 810

Z 905

Z 910

55

1010

10105050

4.944.989.569.94

9.89.84949

504499195203

0.620.610.470.50

100100

33

0.140.140.860.86

57577373

BAS 01 ATEX 7005BAS 01 ATEX 7005BAS 01 ATEX 7005BAS 01 ATEX 7005

Z 713 Z 813 15.75 22 15.75 21.8 723 2.84 0.48 0.076 12.5 BAS 01 ATEX 7005

Z 715Z 715.F

Z 715.1K

Z 815Z 815.F

Z 915

Z 915.1K

1515151515

1001001001k1k

14.714.715.014.715

989898

980980

1501501531515

0.550.550.570.060.06

0.580.620.580.580.58

1.31.451.3144144

646764

570570

BAS 01 ATEX 7005BAS 01 ATEX 7096BAS 01 ATEX 7005BAS 01 ATEX 7005BAS 01 ATEX 7005

Z 722Z 728

Z 728.HZ 728.F

Z 728.H.FZ 728.CL

Z 822Z 828

Z 828.FZ 828.H.FZ 828.CL

Z 928

22282828282828

150300240300240300300

22282828282828

147301235301235301301

15093

11993

1199393

0.820.650.830.650.830.650.65

0.170.0830.0830.0830.0830.0830.083

1.453.051.824.212.593.053.05

45564455445656

BAS 01 ATEX 7005BAS 01 ATEX 7005BAS 01 ATEX 7005BAS 01 ATEX 7096BAS 00 ATEX 7096BAS 01 ATEX 7005BAS 01 ATEX 7005

Z 755 55

1010

4.944.944.94

9.89.84.9

504504

1008

0.620.621.25

100100100

0.140.140.03

575722

BAS 01 ATEX 7005

Z 955 55

1010

4.894.899.78

9.89.84.9

499499998

0..610.611.22

1001003.3

0.140.140.03

575722

BAS 01 ATEX 7005

Z 757

Z 857

Z 961

Z 961.F

Z 961.H

77

99

99

99

1010

100100

100100

360360

7.147.147.148.78.7

17.48.78.7

17.48.78.7

17.4

9.89.84.9989898989898

352.8352.8355

729729

14578989

1788989

178252549

1.31.32.60.190.190.39

0.1920.1920.3840.050.050.11

13.513.513.54.94.9

0.3464.94.90.314.94.9

0.346

0.070.070.024.694.691.144.394.391.075757

15.2

282811

18218272

17617667

613613249

BAS 01 ATEX 7005

BAS 01 ATEX 7005

BAS 01 ATEX 7096

BAS 01 ATEX 7005

Z 764 Z 864 1212

1k1k

11.611.611.6

980980490

121224

0.030.030.06

1.411.411.41

24024061

1.01.0360

BAS 01 ATEX 7005

Z 964 1212

1k1k

121224

980980490

121224

0.040.040.08

1.411.41

0.125

24024061

1.01.0360

BAS 01 ATEX 7005

Z 765

Z 765.F

Z 865

Z 865.F

1515

1515

100100

100100

14.714.714.714.714.714.7

989849989849

150150300150150300

0.550.551.10.550.551.1

0.580.580.580.620.620.62

1.31.3

0.321.451.450.32

646422676722

BAS 01 ATEX 7005

BAS 01 ATEX 7096

2

Data sheet Zener barriers


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Max.end-to-end resistance

Uinat 10 A

Uinmax

Fuse rating see circuitdiagram No.

Circuit diagramHazardous area Safe areaconnections connections

see note 2

V V mA18.1818.18

5656

0.9 (1 A)0.9 (1 A)

6.56.5

4.84.78.99.3

250250100100

1), 2)3)

1), 2)3)

1)

2)

3)

4)

5)

6)

29 13.7 14.6 160

107121107

10251025

13.013.013.013.013.0

13.613.814.013.614.0

10063

100100100

1), 2)

3)3)

1), 2)166327250341273

342 + 2 V327

19.026.526.526.526.526.526.0

20.128.028.028.028.028.027.6

50508050505050

1), 2)1), 2)

1), 2)3)

18.1818.18

0.9 (1 A)0.9 (1 A)

4.84.8

250250

4), 5) A1A2B

18.1818.18

0.9 (1 A)0.9 (1 A)

4.74.7

250250

6) A1A2B

15.515.5

106106

113380

380380

6.06.0

6.56.5

6.56.5

6.56.5

6.96.9

8.18.1

8.08.1

8.18.1

200200

100100

10050

5050

4), 5)

6)

6)

A1A2B

A1A2B

A1A2B

A1A2B

10331033

10.010.0

11.011.0

5050

4), 5) A1A2B

10331033

10.010.0

11.711.7

5050

6) A1A2B

107107

121121

13.013.0

13.013.0

13.613.6

13.913.9

100100

6363

4), 5) A1A2B

A1A2B

+VE type

1 8

2 7

CL

x3

-VE type

1 8

2 7

CL

x3

AC type

1 8

2 7x3x3

+VE type

1 8

4 5

2 7

3 6x3

x3

-VE type

1 8

4 5

2 7

3 6x3

x3

AC type

1 8

4 5

2 7

3 6

x3x3

x3x3



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+ ve - ve a.c. V Uz (V) Rmin () IK(mA) Pmax(W) Cmax (F) Lmax (mH) L/R Ratio Z 966 12

12150150

121224

14714773.5

8282

164

0.240.240.48

1.411.41

0.125

5.525.521.38

14714757

BAS 01 ATEX 7005

Z 966.F

Z 966.H

1212

1212

150150

7575

121224121224

14714773.573.573.536.5

8282

164164164328

0.240.240.490.490.490.98

1.411.41

0.125

1.381.380.33

757536

BAS 01 ATEX 7096

BAS 01 ATEX 7005

Z 772 Z 872 2222

150150

222222

14714773.5

150150300

0.820.821.64

0.170.17

1.451.45

4545

BAS 01 ATEX 7005

Z 778

Z 779

Z 779.H

Z 779.F

Z 779.H.F

Z 878

Z 879

Z 879.H

Z 879.F

Z 879.H.F

2828

2828

2828

28282828

600600

300300

240240

300300240240

28282828282828282828282828

607607

303.5301301

150.5235235

117.5301301235235

4646939393

1861191192389393

120120

0.320.320.650.650.651.3

0.830.831.670.650.650.830.83

0.0830.0830.0830.0830.083

0.0830.083

0.0830.0830.0830.083

17.217.23.053.053.05

1.821.82

4.214.212.592.59

109109425656

4444

55554444

BAS 01 ATEX 7005

BAS 01 ATEX 7005

BAS 01 ATEX 7005

BAS 00 ATEX 7096

BAS 01 ATEX 7096

Z 786 Z 886 282828

DiodeDiodeDiode

282828

DiodeDiodeDiode

000

0.00.00.0

0.0830.0830.083

BAS 01 ATEX 7005

Z 787

Z 787.H

Z 787.F

Z 787.H.F

Z 887

Z 887.H

Z 887.F

Z 887.H.F

2828

2828

2828

2828

300Diode

240Diode

300Diode

240Diode

282828282828282828282828

301Diode301235

Diode23530121.8301

235.214.7

235.2

930

93119

011993

Diode93

120Diode120

0.650

0.650.83

00.830.65

00.650.83

00.83

0.0830.0830.0830.0830.0830.0830.0830.0830.0830.0830.0830.083

3.05

3.052.82

2.824.21

4.212.59

2.59

56

5644

4455

5544

44

BAS 01 ATEX 7005

BAS 01 ATEX 7005

BAS 01 ATEX 7096

BAS 01 ATEX 7096

Z 788

Z 788.H

Z 788.R

Z 888

Z 888.H

2810

2810

2810

30050

24050

30050

289.562828

9.562828

9.5628

3014942

2354940

3014942

9319528811919531493

195288

0.650.470.870.830.471.0

0.650.470.87

0.0833.0

0.0830.083

3.00.0830.083

3.00.083

3.050.860.321.820.860.263.050.860.32

567326447325567326

BAS 01 ATEX 7005

BAS 01 ATEX 7005

BAS 01 ATEX 7005

Z 789 282828

300DiodeDiode

282828

307

91.2

0.638

BAS 01 ATEX 7005

Z 796 Z 896 26.620.5

320415

26.620.526.6

314407177

8550

135

0.560.260.82

0.0940.2040.094

5.1414.62.05

6413834

BAS 01 ATEX 7005

no approval for IIC

no approval for IIC

no approval for IIC

see note 1

4



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Uinat 10 A

Uinmax



see note 2

V V mA166166

10.010.0

11.711.7

5050

6) 4)

5)

6)

7)

8)

9)

A1A2B

169169

8282

10.010.0

10.010.0

11.911.9

11.711.7

6363

100100

6)

A1A2BA1A2B

166166

19.019.0

20.120.1

5050

4), 5) A1A2B

646646

327327

250250

341341273273

26.526.5

26.526.5

26.526.5

26.526.626.526.5

28.028.0

28.028.0

28.028.0

28.028.028.028.0

5050

5050

8080

50505050

4), 5)

4), 5)

4), 5)

A1A2BA1A2BA1A2B

36 + 0.9 V36 + 0.9 V

26.526.5

28.028.0

5050

8) A1A2B

32736 + 0.9 V

25025 + 0.9 V

34150 + 0.9 V

27343 + 0.9 V

26.526.5

26.526.5

26.526.5

26.526.5

28.028.0

28.028.0

28.028.0

28.028.0

5050

8080

5050

5050

9)

9)

A1A2BA1A2BA1A2BA1A2B

32764

25064

32764

26.56.5

26.56.5

26.5

28.09.1

28.09.1

28.09.1

5050

8080

5050

4), 5)

4), 5)

7)

A1A2BA1A2BA1A2B

64036 + 0.9 V36 + 0.9 V

26.526.526.5

27.527.527.5

505050

??? A1A2B

340437

24.018.0

25.119.5

5050

4), 5) A1A2B

+VE type

1 8

4 5

2 7

3 6x3

x3

-VE type

1 8

4 5

2 7

3 6x3

x3

AC type

1 8

4 5

2 7

3 6

x3x3

x3x3

AC type

All diodes are turned 180 for the -VE version.

1 8

4 5

2 7

3 6

x3

x3


1 8

4 5

2 7

3 6

x3

x3


1 8

4 5

2 7

3 6

x3

x3



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+ ve - ve a.c. V Uz (V) Rmin () IK(mA) Pmax(W) Cmax (F) Lmax (mH) L/R Ratio

Z 960

Z 960.F

1010

1010

5050

5050

9.949.949.949.949.949.94

4949

24.5984949

203203406203203406

0.500.501.0

0.510.511.02

3;03;03;0

2.632.632.63

0.860.860.190.820.820.82

737326696925

BAS 01 ATEX 7005

BAS 01 ATEX 7096

Z 965 1515

100100

151515

989849

153153306

0.570.571.14

0.580.580.58

1.31.3

0.29

646420

BAS 01 ATEX 7005

Z 967 1717

120120

16.816.816.8

11711758

143143286

0.600.601.20

0.380.380.38

1.631.630.24

606021

BAS 01 ATEX 7005

Z 972 2222

300300

222222

301301150

7373146

0.400.400.80

0.170.170.17

6.956.951.45

909035

BAS 01 ATEX 7005

Z 978 2828

600600

282828

607607304

464693

0.320.320.65

0.0830.0830.083

17.217.23.05

10910942

BAS 01 ATEX 7005

Z 954 4.54.54.5

121212

4.54.54.59.09.09.0

11.7611.7611.765.883.92

17.64

383383383765

1150510

0.430.430.430.861.291.15

1001001004.94.94.9

0.240.240.24

0.0680.030.12

818181412730

BAS 01 ATEX 7005

DummyZ 799

6



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Note 1:Zener barriers type Z 787H and Z 887H have channels with diode returns.The intrinsically safe terminals for the channels with diode returns should be regarded as 28 V voltage sources.The 28 V must be considered as the theoretical maximum up to which a capacitive load can be applied to the intrinsically safe terminals due to the leakage current of the diode return. This voltage is only used in calculating the load capacitance.

Note 2:A1, A2 and A3 are separate channels.B: Two channels in parallel circuit with a ground connection.C: Two channels in series circuit without a ground return.


Uinat 10 A

Uinmax



see note 2

V V mA6464

7979

6.56.5

6.56.5

9.59.5

9.79.7

5050

5050

10) 10)

11)

A1A2B

A1A2B

115115

13.013.0

14.214.2

5050

10) A1A2B

136136

15.015.0

16.216.2

5050

10) A1A2B

327327

19.019.0

20.920.9

5050

10) A1A2B

646646

26.026.0

27.627.6

5050

10) A1A2B

27.2727.2727.27

0.9 (1 A)0.9 (1 A)0.9 (1 A)

4.94.94.9

505050

11) A1A2A3BBC

1 8

4 5

2 7

3 6x3

x3

1 8

4 5

3 6

2 7

x3

x3

x3

1 8

4 5

2 7

3 6



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0.1 Application examplesTemperature measurement

The simplest and most favourably priced solution is a single-channel Zener barrier. It should be noted, however, that the

device is not grounded in the safe area. The system is approved for [EEx ia] IIC.

The use of a two-channel barrier prevents the direct ground connection of the intrinsically safe circuit. Grounding only takes place in the event of a fault, when the Zener diodes conduct.

This circuit arrangement prevents the occurrence of mutual interference between the various circuits. The system is approved for [EEx ia] IIC.

The illustration shows the set up for a temperature measurement with a 4-wire Pt100. None of the 4 wires is connected directly to ground. The complete system is therefore "quasi ground-free".

This is the best option when the intention is to suppress the influence of the end-to-end resistance of the barrier on the measuring accuracy as far as possible.

Temperaturemonitoringor control

Hazardous area Safe area

Not groundedZ705

x3

CL1

2

8

7

Temperaturemonitoringor control

Hazardous area Safe areaZ960

x3x3

x3

1

2

34

8

7

65


V

Z961

x3x3

x3x3

1

2

34

8

7

65

Z961

x3x3

x3x3

1

2

34

8

7

65

8



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Temperature measurement

The circuit arrangement shows the connection of a Pt100 in 3-wire technology, using the 3-channel Zener barrier Z 954. The whole system is quasi ground-free. All 3 barriers have identical

end-to-end resistances, so that the resulting error is restricted to a minimum. The system is approved for [EEx ia] IIC.

The circuit consists of a system of a maximum of seven Pt100s. The Pt100s are connected in series to a constant current source. Each voltage signal is transferred to a receiver via a Z 954.

The Z 954s have been selected due to their high end-to-end resistance. Due to the high input resistance of the receiver, the high end-to-end resistance has practically no effect on the accuracy of measurement.


Test circuit

1

3

2

4

Z954

x3x3

x3x3

x3x3

8

6

7

5


Receiver with galvanically

isolated inputs

Z961

x3x3

x3x3

1

2

34

8

7

65

Z954

x3x3

x3x3

x3x3

1

3

2

4

8

6

7

5

1

3

2

4

8

6

7

Z954

x3x3

x3x3

x3x3 5



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0 mA 20 mA/4 mA 20 mA transmitter

If a ground-free power supply is available, the use of a single-channel Zener barrier, grounded in the safe area, represents the simplest and most economical solution. The ammeter can be used in combination with a recording instrument, a trip amplifier, or a 250 resistance, or replaced by these devices. In so doing, the overall resistance of the arrangement must be taken into account. The working range of the barrier caters for

an input voltage of up to 27 V. For each built-in 250 resistance the output voltage of the power supply can be increased by 1 V. By using a 250 resistance and a supply voltage of 28 V, a source of 16.5 V at 20 mA is available to the transmitter in the hazardous area. The internal voltage drop across the barrier is then 6.5 V. The system is approved for [EEx ia] IIC.

With this 2-channel Zener barrier, it is possible to supply a number of circuits with one source. All the wiring is quasi ground-free. The maximum voltage supply is 27 V. The internal voltage drop across the barrier is 7.8 V at 20 mA, so that 19.2 V are available for the field device and ammeter. If the

ammeter for converting the current signal into a 1 V 5 V voltage signal is replaced by a 250 resistance, then 14.2 V are available at the field device. The system is approved for [EEx ia] IIC.


A

Z728

x3

CL1

2

8

7


x3

x3

1

2

34

8

7

65

A

10



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0 mA 20 mA/4 mA 20 mA transmitter

This system can be used if the field device requires a relatively high voltage. A 250 resistance is connected in parallel with the intrinsically safe output of the 10 V/50 output of this 2-

channel barrier. Thus a voltage of 15.5 V is available at the field device if the voltage supply is 27 V. The system is approved for [EEx ia] IIC.

The combination of a 28 V, 300 and a 28 V barrier with diode return is the solution for applications with 3-wire transmitters. Special attention must be paid here to the internal voltage

drop. The reason for this is the diode return. The system is approved for [EEx ia] IIC.

Hazardous area Safe areaZ788.R

x3

x3

1

2

34

8

7

65

V


x3

x3x3

1

2

3

4

8

7

6

5A

11



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SMART transmitter

The simplest possible solution is the use of a 2-channel Zener barrier with 28 V, 300 and 28 V diode return. If a regulated power supply unit provides an output voltage of 27 V, 13.9 V will be available to the transmitter and wiring in the hazardous area.

The data transfer is bidirectional, so that a non-certificated communicator can be connected and used in the the safe area. The system is approved for [EEx ia] IIC.

Strain gauge bridges

The strain gauge bridge is supplied via the Z 966. The Z 966 enables a 350 strain gauge bridge to be supplied with 8 V. The voltage feedback via the Z 964 can be dispensed with, although in practice most applications require this feedback to

obtain the best possible accuracy of measurement.The millivolt signal is transferred to the safe area via the Z 964. The system is approved for [EEx ia] IIC.


A

8

7

65

1

2

34

x3

x3


Signal

Z966

x3x3

x3x3

1

2

34

8

7

65

Z964

x3x3

x3x3

1

2

34

8

7

6

+

-

5

Z964

x3x3

x3x3

1

2

34

8

7

65

12



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Wire strain gauges

If more than one strain gauge bridge is to be supplied from a common power supply (in the example shown above there are three), a possible solution is to supply them via two Z 966s, as shown.

Both channels of these Zener barriers are arranged in parallel in order to reduce the end-to-end resistance. This arrangement provides 8 V to the bridges if the voltage supply is 20 V. The system is approved for [EEx ib].


Sensor +

Sensor -

350

350

350

1

2

34

Z966

x3x3

x3

8

6x3

7

5

Z966

1

2

34

8

6

x3

x3

7

5

x3

x3

Z964

x3

x3

x3

x3

1

2

34

8

7

65

Z964

x3x3

x3x3

1

2

34

8

7

65

- 0 +

13



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Potentiometric position detection

Applications in which the accuracy is not critical can be satisfied as shown above. The intrinsically safe circuit has a direct connection to ground. An additional resistance on this

side would have an effect on the voltage signal and would have to be taken into account. The system is approved for [EEx ia] IIC.

If greater accuracy is required, a 4-wire solution must be applied. The Z 715 Zener barrier transfers the power supply to the potentiometer, whilst two Z 715.1K barriers transfer the

signal to the receiver. The supply voltage in the example above could be 13 V.


V

Z960

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x3

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2

34

8

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65

Harzardous area Safe area

Signal

Z715

x3

CL1

2

8

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Z715.1K

x3

CL1

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Z715.1K

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Solenoid valves

The simplest and most economical solution is a single channel Zener barrier, with the power supply grounded on its safe side. If the valve requires 30 mA at a minimum 12 V, then at a

supply voltage of 27 V, 4 V would remain for the voltage drop through the field wiring. The system is approved for [EEx ia] IIC.

If the switch is in parallel circuit with the nominal mains voltage, it is usual to use a barrier combination of 28 V, 300 and a 28 V diode return. In this solution, special attention has to be

paid to the voltage drop in the barrier, since the diode return causes an additional loss of voltage. The system is approved for [EEx ia] IIC.


x3

CL1

2

8

7


x3

x3

1

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32

8

5

67

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Switch status

In the traditional method of switch status detection, the switch is provided with noble metal contacts suitable for low voltages and currents. A ground fault in any field wire leaves the relay in the de-energised state, despite the switch being closed. This problem is solved by the use of quasi ground-free wiring.

At a nominal voltage of up to 27 V, a typical coil with 12 V and approx. 350 can be used to match the power. The Zener barrier is approved for [EEx ia] IIC. Negative polarities can be accommodated with the Z 887.

Hazardous area Safe areaZ787 Z887

x3

x3

1

4

32

8

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Z789

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4

3

2

1

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Pulse transmission and flow measurement

The simplest method of flow measurement, with or without a pre-amplifier, is illustrated in the circuit above. The flow meter sensor generates voltage or current pulses, which are transmitted to the safe area via the Z 728. If the sensor

generates sinusoidal signals, e. g. an inductive sensor, a Zener barrier for alternating polarities can be used, for example the Z 928. The Zener barrier is approved for [EEx ia] IIC.

If the power supply to the flow meter is provided via a 28 V, 300 barrier and ground, the signal can be transferred via the diode return of the Z 787. When selecting the receiver

(counter), consideration must be given to the fact that the high signal is damped by the diode. The system is approved for [EEx ia] IIC.

LED display

The simplest and most economical solution is the single-channel Zener barrier shown above. The nominal supply voltage is sufficiently low that the end-to-end resistance of the

barrier limits the flow of current through the LED to an acceptable value. Otherwise a current-limiting resistor is required. The system is approved for [EEx ia] IIC.


Output

Flow meter withpulse output

Z728

x3

CL1

2

8

7


Output

Flow meter withpulse output 1

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Z787

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LED display

The circuit shown above does not require a current limiting resistor, since the Z 728.CL limits the current electronically to a maximum of 40 mA. At a supply voltage of 18 V 27 V a current of 40 mA flows in the intrinsically safe circuit. This

current reduces at lower nominal supply voltages. To special order, the Z 728.CL can be supplied with lower current-limiting values. The system is approved for [EEx ia] IIC. The Z 828.CL is also suitable for negative polarities.

Smoke and fire alarms

The simplest and most cost-effective solution is shown in the illustration above. With a 24 V nominal supply voltage, there is an off-state current of approx. 4 mA. When the detector responds, the current increases to approx. 25 mA or greater.

The current applied to the detector is sufficient to operate the LED display with sufficient brightness. The system is approved for [EEx ia] IIC.

The system shown above is comparable to the Z 728 and is also relatively inexpensive. The Z 787 is a 2-channel device. In

this application the intrinsically safe circuit is quasi ground-free. The system is approved for [EEx ia] IIC.

Hazardous area Safe areaZ728.CL

x3

1

2

8

7

CL

Hazardous area Safe areaOutput

I

Z728

x3

CL1

2

8

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Hazardous area Safe areaOutput

I

Z787

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4

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Audible alarms

Audible alarms operate at relatively high voltages and low currents. They are approved for use with various Zener

barriers. The simplest solution is the circuit shown above.

I/P converters

The simplest and most cost-effective solution is a single-channel Zener barrier. The nominal supply control voltage must either be ground-free or connected to the negative output to earth. In theory, the field circuit can have a resistance of

900 if the voltage supply is 27 V. In practice, however, the voltage values are lower, so that the field circuit normally has a resistance of 300 .


x3

CL1

2

8

7


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I

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34

Z787

x3

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8

7

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Documents

Tmdoc0328d Eng