Description

Details: KFD2-SRA-Ex4

  • 4-channel isolated barrier
  • 24 V DC supply (Power Rail)
  • Dry contact or NAMUR inputs
  • 50 % less wiring, 2:1 technology
  • Relay contact output
  • Line fault detection (LFD)
  • Reversible mode of operation

Function

This isolated barrier is used for intrinsic safety applications. It transfers digital signals (NAMUR sensors/mechanical contacts) from a hazardous area to a safe area.

Each sensor or switch controls one form A normally open relay contact for the safe area load. A special 2:1 wire saving technology is available on this isolator, reducing field wiring by 50 %.

Switch S1 is used to enable or disable line fault detection of the field circuit. The 2:1 mode is selected with switch S2 while the remaining switches, S3 … S6, are used for reversing the normal output state of the relays.

A unique collective error messaging feature is available when used with the Power Rail system.

 

Datasheet excerpt:  Technical Data of KFD2-SRA-EX4

General Specifications

Signal type                         Digital Input

 

Supply

Connection                         Power Rail or terminal 14+,  15-

Rated Voltage                    19 … 30 V DC

Ripple                                  ≤ 10%

Rated Current                    45 … 70mA

Power Dissipation             1.2 W

 

Input

Connection Side               Field Side

Connection                        Terminal 1-, 2+, 3-; 4-, 5+, 6-

Switching point                 1.2 … 2.1 mA / approx. 0.2 mA

Open circuit voltage        approx. 8 V DC / approx. 8 mA

Pulse                                    min. 35 ms / min. 35 ms (non-AC operation) min. 70 ms / min. 70 ms (AC operation)

Line fault detection          breakage I ≤ 0.15 mA, short-circuit I > 6 mA

 

Ouput

Connection side                control side

Connection                        output I: terminal 7 , 8 ; output II: terminal 8 , 9 ; output III: terminal 10 , 11 ; output    IV: terminal 11 , 12

Output I … IV                     Signal I … Signal IV ; relay

Energized                           approx.. 30 ms / approx.. 30 ms

 

Transfer Characteristics

Switch frequency              ≤ 10 Hz (non-AC operation) ≤  3 Hz (AC operation)

 

Indicators/settings

Display elements              LEDs

Control elements              DIP switch

Configuration                    vis DIP switches

Labeling                              space for labeling at the front

 

Conformity

Electromagnetic                NE 21 : 2006

Degree of protection       IEC 60529: 2001

Input                                    EN 60947-5-6:2000

 

Ambient conditions

Ambient temperature     -20 ….. 60 °C (-4 … °F)

 

Mechanical specifications

Degree of protection       IP20

Connection                         Screw terminals

Mass                                   approx. 150g

Dimension                          20 * 119 * 115 mm (0.8 * 4.7 * 4.5 inch)

                                           (W * H * D), housing type B2