INTRINSIC SAFETY BARRIER

ZENER BARRIERS

Zener barriers are a cost-eff ective solution for providing an intrinsically safe interface with field devices located in the hazardous area. As part of the intrinsic safety barrier family, Pepperl+Fuchs off ers two distinct zener barrier systems. The Z-System barriers are 12.5 mm wide and mount and ground directly to standard 35 mm DIN rail, while the SB-System barriers are the only termination board solution with pluggable modules available on the market. In addition to this wide product portfolio of housing and connection styles, we off er accessories for each application.

KCD2-SON-Ex1.R1 Switch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR input, 2 passive transistor outputs (resistive), Application-specific outputs, Line fault transparency (LFT), Usable as signal splitter (1 input and 2 outputs), Housing width 12.5 mm, Up to SIL 2 acc. to IEC 61508
KCD2-SON-Ex1.R2 Switch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR input, Application-specific outputs, Usable as signal splitter (1 input and 2 outputs), 2 passive transistor outputs (resistive), Line fault transparency (LFT), Housing width 12.5 mm, Up to SIL 2 acc. to IEC 61508
KCD2-SON-Ex1.R3 Switch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR input, Application-specific outputs, Usable as signal splitter (1 input and 2 outputs), 2 passive transistor outputs (resistive), Line fault transparency (LFT), Housing width 12.5 mm, Up to SIL 2 acc. to IEC 61508
KCD2-SON-Ex2 Switch Amplifier2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, 2 passive transistor outputs (resistive acc. to EN 60947-5-6), Line fault transparency (LFT), Housing width 12.5 mm, Up to SIL 2 acc. to IEC 61508
KCD2-SON-Ex2.R1 Switch Amplifier2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, 2 passive transistor outputs (resistive), Application-specific outputs, Line fault transparency (LFT), Housing width 12.5 mm, Up to SIL 2 acc. to IEC 61508
KCD2-SON-Ex2.R2 Switch Amplifier2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Application-specific outputs, 2 passive transistor outputs (resistive), Line fault transparency (LFT), Housing width 12.5 mm, Up to SIL 2 acc. to IEC 61508

KCD2-SON-Ex2.R3 Switch Amplifier 2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Application-specific outputs, 2 passive transistor outputs (resistive), Line fault transparency (LFT), Housing width 12.5 mm, Up to SIL 2 acc. to IEC 61508 KCD2-SOT-Ex2.SP Switch Amplifier 2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, 2 passive transistor outputs, Reversible mode of operation, Line fault detection (LFD), Housing width 12.5 mm, Connection via spring terminals with push-in connection technology, Up to SIL 2 acc. to IEC 61508 KCD2-SR-Ex1.LB.SP Switch Amplifier 1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Usable as signal splitter (1 input and 2 outputs), Relay contact output, Fault relay contact output, Line fault detection (LFD), Housing width 12.5 mm, Connection via spring terminals with push-in connection technology, Up to SIL 2 acc. to IEC 61508 KCD2-SR-Ex2.SP Switch Amplifier 2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Relay contact output, Line fault detection (LFD), Housing width 12.5 mm, Connection via spring terminals with push-in connection technology, Up to SIL 2 acc. to IEC 61508

ISOLATED BARRIERS – DIN RAIL MOUNTED
K-System isolated barriers guarantee safe, reliable, and effi cient signal transmission between your fi eld device and the control system. In addition to their inherent power limitation, these modules feature galvanic isolation between the signal loop and all other power loops. Pepperl+Fuchs off ers the most complete range of products to meet all your application and installation requirements.

KCD2-ST-Ex1.LB Switch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR input, 2 active transistor outputs, Usable as signal splitter (1 input and 2 outputs), Reversible mode of operation, Line fault detection (LFD), Housing width 12.5 mm, Up to SIL 2 acc. to IEC 61508
KFA4-SR2-Ex1.W Switch Amplifier1-channel, Control circuit EEx ia IIC, Reversible mode of operation, 1 relay contact output (change-over contact), EMC acc. to NAMUR NE 21, LB/SC monitoring, Up to SIL 2 acc. to IEC 61508/IEC 61511
 KFA4-SR2-Ex1.W.LB Switch Amplifier1-channel, Control circuit EEx ia IIC, Reversible mode of operation, Output I: relay contact output (change-over contact), Output II: optionally signal output/fault signal, EMC acc. to NAMUR NE 21, LB/SC monitoring, Up to SIL 2 acc. to IEC 61508/IEC 61511
KFA4-SR2-Ex2.W Switch Amplifier2-channel, Control circuit EEx ia IIC, Reversible mode of operation, 1 relay contact output (change-over contact) per channel, EMC acc. to NAMUR NE 21, LB/SC monitoring, Up to SIL 2 acc. to IEC 61508/IEC 61511
 KFA5-DU-Ex1.D Switch Amplifier, Timer Relay1-channel isolated barrier, 115 V AC supply, Dry contact or NAMUR inputs, Relay contact and transistor output, Adjustable output timer functions from 10 ms ... 60 min, Input frequency up to 80 Hz; pulse divider up to 1 kHz, Reset function, Configurable by keypad, Line fault detection (LFD)
 KFA5-SR2-Ex2.W.IR Switch Amplifier2-channel isolated barrier, 115 V AC supply, Dry contact or NAMUR inputs, Latching relay contact output, Line fault detection (LFD)
KFA6-DU-Ex1.D Switch Amplifier, Timer Relay1-channel isolated barrier, 230 V AC supply, Dry contact or NAMUR inputs, Relay contact and transistor output, Adjustable output timer functions from 10 ms ... 60 min, Input frequency up to 80 Hz; pulse divider up to 1 kHz, Reset function, Configurable by keypad, Line fault detection (LFD)
KFA6-ER-Ex1.W.LB Conductivity Switch Amplifier1-channel isolated barrier, 230 V AC supply, Level sensing input, Adjustable range 1 kΩ ... 150 kΩ, Relay contact output, Fault relay contact output, Adjustable time delay up to 10 s, Minimum/maximum control, Line fault detection (LFD)
KFA6-SR2-Ex2.W.IR Switch Amplifier2-channel isolated barrier, 230 V AC supply, Dry contact or NAMUR inputs, Latching relay contact output, Line fault detection (LFD)
 KFD2-DU-Ex1.D Switch Amplifier, Timer Relay1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Relay contact and transistor output, Adjustable output timer functions from 10 ms ... 60 min, Input frequency up to 80 Hz; pulse divider up to 1 kHz, Reset function, Configurable by keypad, Line fault detection (LFD)

KFD2-ELD-Ex16 Ground Fault Detection 16-channel isolated barrier, 24 V DC supply (Power Rail), Analog or digtial field device inputs, Monitors leakage current, Fault relay contact output, LED status indication, Test circuit for validation, Parallel connection for easy integration, Conformal coating KFD2-SOT3-Ex1.LB.IO Switch Amplifier 1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Usable as signal splitter (1 input and 2 outputs), Isolated passive transistor output, non-polarized, Isolated passive fault output, non-polarized, Line fault detection (LFD), Reversible mode of operation, Up to SIL 2 acc. to IEC 61508

MTL7700 range
DIN-rail mounting safety barriers

•     Removable terminals
•     Bussed power feed to other modules
•     Relay and solid state switch modules
•     Dual channel variants – 6.3mm per channel
•     Proximity detector inputs
•     Electronic fusing
•     Direct replacement for MTL700 range    barriers
•     Compatible terminal numbering and safety descriptions

The MTL7700 range follows closely in the footsteps of the MTL700, but as a DIN rail mounting barrier, providing quick and easy installation without the need for special hardware

Removable terminals are used for ease of installation, maintenance and for providing a loop disconnect by simply unplugging the terminals from the side of the module. 

MTL7700 barriers clamp simply and securely onto standard T-section DIN rail, simultaneously making a reliable IS earth connection.

For applications where field power is required for switch inputs or 2-wire transmitters, the MTL7700 range provides a bussed power feed facility. When used in conjunction with the MTL7798 power feed module the user has a fully protected, electronically fused supply to many barriers with no additional wiring required.

MTL7700 active modules are protected with an electronic fuse for the majority of applications. 


KFD2-CRG2-Ex1.DTransmitter Power Supply
KFD2-GUT-Ex1.DTemperature Converter with Trip Values
KFU8-CRG2-Ex1.DTransmitter Power Supply
KFU8-GUT-Ex1.DTemperature Converter with Trip Values
KFD2-WAC2-Ex1.DStrain Gauge Converter
KFD2-WAC2-Ex1.D-Y1Strain Gauge Converter


KFD0-SCS-Ex1.55SMART Current Driver/Repeater
KFD2-SCD2-Ex1.LKSMART Current Driver
KFD2-SCD2-Ex2.LKSMART Current Driver
KCD2-SCD-Ex1SMART Current Driver
KFD0-CS-Ex1.50PRepeater
KFD0-CS-Ex1.51PCurrent Driver/Repeater
KFD0-CS-Ex2.51PCurrent Driver/Repeater
KCD2-SCD-Ex1.SPSMART Current Driver
KFD0-CS-Ex2.50PRepeater
KFD2-SCD-Ex1.LKSMART Current Driver


Z713Zener Barrier
Z715Zener Barrier
Z728Zener Barrier
Z728.HZener Barrier
Z765Zener Barrier
Z778Zener Barrier
Z779Zener Barrier
Z787Zener Barrier
Z787.HZener Barrier
Z788Zener Barrier
Z788.HZener Barrier
Z928Zener Barrier
Z954Zener Barrier
Z960Zener Barrier
Z961Zener Barrier
Z961.HZener Barrier
Z964Zener Barrier
Z965Zener Barrier
Z966Zener Barrier
Z966.HZener Barrier
Z779.FZener Barrier
Z779.HZener Barrier
Z787.FZener Barrier

Z787.H.FZener Barrier
Z896Zener Barrier
Z955Zener Barrier
Z967Zener Barrier
Z040Zener Barrier
Z041Zener Barrier
Z042Zener Barrier
Z705Zener Barrier
Z710Zener Barrier
Z715.1KZener Barrier
Z715.FZener Barrier

Z722Zener Barrier
Z728.CLZener Barrier
Z728.FZener Barrier
Z728.H.FZener BarrierZ755Zener Barrier
Z757Zener Barrier
Z764Zener Barrier
Z765.FZener Barrier
Z772Zener Barrier
Z779.H.FZener Barrier
Z786Zener Barrier
Z788.RZener Barrier
Z789Zener Barrier
Z796Zener Barrier
Z810Zener Barrier
Z813Zener Barrier
Z822Zener Barrier
Z828Zener Barrier
Z857Zener Barrier
Z864Zener BarrierZ878Zener BarrierZ887Zener BarrierZ888Zener Barrier
Z905Zener BarrierZ910Zener BarrierZ915Zener BarrierZ915.1KZener Barrier
Z960.FZ961.FZ966.FZ972Z978Z810.CLZ828.HZ828.H.FZ865Z865.FZ872Zener BarrierZ879.FZ879.H.FZener BarrierZ886Z887.FZener BarrierZ887.H.FZener BarrierZ888.HZener Barrier

KCD2-STC-Ex1.2O
< 1-channel isolated barrier
< 24 V DC supply (Power Rail)
< Input for 2-wire SMART transmitters and current sources
< Signal splitter (1 input and 2 outputs)
< Dual output 0/4 mA ... 20 mA or 0/1 V ... 5 V
< Terminal blocks with test sockets
< Up to SIL 2 acc. to IEC 61508This isolated barrier is used for intrinsic safety applications. The device supplies 2-wire transmitters in the hazardous area, and can also be used with current sources. It transfers the analog input signal to the safe area as two isolated output signals. Bi-directional communication is supported for SMART transmitters that use current modulation to transmit data and voltage modulation to receive data. The output is selected as a current source, current sink, or voltage source via switches. Test sockets for the connection of HART communicators are integrated into the terminals of the device
Signal type- Analog input
Connection Power Rail or terminals 9+, 10-
Rated voltage Ur 18 ... 30 V DC
Ripple within the supply tolerance
Power dissipation approx. 1.4 W at 20 mA transfer current, 250 Ω in both outputs
Power consumption 2 W
The device supports the following SMART protocols:
• HART
• BRAIN

• 1-channel
• Output EEx ia IIC
• 24 V DC nominal supply voltage
• Device installation permissible in zone 2
• Conversion of current/voltage or voltage/current
• Elevation/Suppression of the "life zero"
• Accuracy 0.1 %
• EMC acc. to NAMUR NE 21 KFD2-CD-Ex1.32
The KFD2-CD-Ex1.32 transmits an electrical unit signal from the safe area to the hazardous area. The conversion of a current signal into a voltage signal and vice versa is possible. Current input option A current limit circuit in series to terminal 9 protects the device from damage. The max. voltage drop at the input is DC 4 V, allowing for the connection of several KFD2-CD32-Ex1.32 repeaters due to the low voltage drop in order to maintain multiple galvanically isolated outputs (signal duplication). Voltage input option The signal is transmitted to terminals 9 and 10 across an amplifier and the DC/DC converter within the allowable voltage range. A voltage limiter circuit protects the amplifier from incorrect input switching and overvoltage, but will draw current through a 50 mA fuse during operation. The fuse can be changed only by the manufacturer. Current output option The open circuit voltage is DC 24 V within the allowable supply voltage range at terminals 1 and 2. The max. load that can be applied is 850 ???. Voltage output option At least 20 mA is available within the allowable supply voltage range at terminals 1 and 2 which means that with 10 V output voltage, a load of at least 500 ??? must be connected
Used to drive I/P converters and valve positioners. Table: input/output options, type For options enclosed in parantheses, the transfer range for a base type is only partially used, i. e. 4 mA ... 20 mA from the base type 0 mA ... 20 mA.

• 1-channel isolated barrier
• 24 V DC supply (loop powered)
• Current limit 45 mA at 10 V DC
• Up to SIL 3 acc. to IEC 61508 This isolated barrier is used for intrinsic safety applications. The device supplies power to solenoids, LEDs and audible alarms located in a hazardous area. The device is loop powered, so the available energy at the output is received from the input signal. The output signal has a resistive characteristic. As a result the output voltage and current are dependent on the load and the input voltage At full load, 10 V at 45 mA is available for the hazardous area application

ISOLATED BARRIERS – DIN RAIL MOUNTED
K-System isolated barriers guarantee safe, reliable, and effi cient signal transmission between your fi eld device and the control system. In addition to their inherent power limitation, these modules feature galvanic isolation between the signal loop and all other power loops. Pepperl+Fuchs off ers the most complete range of products to meet all your application and installation requirements.


KCD2-SON-Ex1.SPSwitch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR input, 2 passive transistor outputs (resistive acc. to EN 60947-5-6), Line fault transparency (LFT), Housing width 12.5 mm, Connection via spring terminals with push-in connection technology, Up to SIL 2 acc. to IEC 61508
KCD2-SON-Ex2.SPSwitch Amplifier2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, 2 passive transistor outputs (resistive acc. to EN 60947-5-6), Line fault transparency (LFT), Housing width 12.5 mm, Connection via spring terminals with push-in connection technology, Up to SIL 2 acc. to IEC 61508
KCD2-SOT-Ex1.LB.SPSwitch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR input, 2 passive transistor outputs, Usable as signal splitter (1 input and 2 outputs), Reversible mode of operation, Line fault detection (LFD), Housing width 12.5 mm, Connection via spring terminals with push-in connection technology, Up to SIL 2 acc. to IEC 61508
KCD2-ST-Ex1.LB.SPSwitch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR input, 2 active transistor outputs, Usable as signal splitter (1 input and 2 outputs), Reversible mode of operation, Line fault detection (LFD), Housing width 12.5 mm, Connection via spring terminals with push-in connection technology, Up to SIL 2 acc. to IEC 61508
KCD2-ST-Ex2.SPSwitch Amplifier2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, 2 active transistor outputs, Reversible mode of operation, Line fault detection (LFD), Housing width 12.5 mm, Connection via spring terminals with push-in connection technology, Up to SIL 2 acc. to IEC 61508
KFD2-SOT2-Ex1.LBSwitch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Passive transistor output, non-polarized, Passive fault output, non-polarized, Line fault detection (LFD), Reversible mode of operation, Up to SIL 2 acc. to IEC 61508
KFD2-SOT2-Ex1.LB.IOSwitch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Usable as signal splitter (1 input and 2 outputs), Isolated passive transistor output, non-polarized, Isolated passive fault output, non-polarized, Line fault detection (LFD), Reversible mode of operation, Up to SIL 2 acc. to IEC 61508
KFD2-SOT2-Ex2Switch Amplifier2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Passive transistor output, non-polarized, Line fault detection (LFD), Reversible mode of operation, Up to SIL 2 acc. to IEC 61508

KFD2-SOT2-Ex2.IOSwitch Amplifier2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Isolated passive transistor output, non-polarized, Line fault detection (LFD), Reversible mode of operation, Up to SIL 2 acc. to IEC 61508
KFD2-SR2-Ex2.2SSwitch Amplifier2-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Usable as signal splitter (1 input and 2 outputs), 2 x 2 relay contact outputs with AND logic, Line fault detection (LFD), Reversible mode of operation, Up to SIL 2 acc. to IEC 61508
KFD2-ST2-Ex1.LBSwitch Amplifier1-channel isolated barrier, 24 V DC supply (Power Rail), Dry contact or NAMUR inputs, Active transistor output, Active fault output, Line fault detection (LFD), Reversible mode of operation, Up to SIL 2 acc. to IEC 61508

Shunt-Diode Safety Barriers and Galvanic Isolators  a Critical Comparison By L C Towle BSc CEng MIMechE MIEE MInstMC Technology Director The MTL Instruments Group plc Introduction The discussion on the relative merits of galvanic isolators and shunt diode safety barriers has been carried on for many years. The majority of other articles on this subject have aimed to prove the superiority of one technique over the other. This paper brings together the illustrations which have accumulated over a considerable time in response to various questions raised at presentations. It attempts to make balanced arguments so that the reader can decide the most suitable technique for a particular application. It ends with a score sheet which might be found useful if a decision is not completely self revealing. The paper has evolved over a considerable time, however it is unlikely that it covers all aspects and will inevitably need to be revised as techniques develop. If you have any comments on the contents or omissions within this document the author would like to receive them. In this way the document will become more comprehensive and more valuable.