SMART Transmitter Power Supply, KFD2-STC4-Ex1

• 1-channel isolated barrier
• 24 V DC supply (Power Rail)
• Input 2-wire and 3-wire SMART transmitters and 2-wire SMART current sources
• Output 0/4 mA ... 20 mA
• Terminals with test points
• Up to SIL 2 acc. to IEC/EN 61508

This isolated barrier is used for intrinsic safety applications.

The device supplies 2-wire and 3-wire SMART transmitters in a hazardous area, and can also be used with 2-wire SMART current sources.

It transfers the analog input signal to the safe area as an isolated current value.

Digital signals may be superimposed on the input signal in the hazardous or safe area and are transferred bi-directionally.

If the HART communication resistance in the loop is too low, the internal resistance of 250 Ω between terminals 8 and 9 can be used.

Test sockets for the connection of HART communicators are integrated into the terminals of the device.

Product Description
Input 0/4 mA ... 20 mA
Output 0/4 mA ... 20 mA
General specifications
Signal type	Analog input
Functional safety related parameters
Safety Integrity Level (SIL)	SIL 2
Supply
Connection	Power Rail or terminals 14+, 15-
Rated voltage	20 ... 35 V DC
Ripple	within the supply tolerance
Power dissipation	1.4 W
Power consumption	1.8 W
Input
Connection side	field side
Connection	terminals 1+, 2-, 3 or 5-, 6+
Input signal	0/4 ... 20 mA
Voltage drop	≤ 2.4 V at 20 mA (terminals 5, 6)
Input resistance	≤ 64 Ω terminals 2-, 3 ; ≤ 500 Ω terminals 1+, 3 (250 Ω load)
Available voltage	≥ 16 V at 20 mA, terminals 1+, 3
Output
Connection side	control side
Connection	terminals 7-, 8+, 9
Load	0 ... 800 Ω at 20 mA
Output signal	0/4 ... 20 mA (overload > 25 mA)
Ripple	max. 50 µA rms
Transfer characteristics
Deviation	at 20 °C (68 °F), 0/4 ... 20 mA
	≤ 10 µA incl. calibration, linearity, hysteresis, loads and fluctuations of supply voltage
Influence of ambient temperature	0.25 µA/K
Frequency range	field side into the control side: bandwidth with 0.5 Vpp signal 0 ... 7.5 kHz (-3 dB) safe area to hazardous area: bandwidth with 0.5 Vpp signal 0.3 ... 7.5 kHz (-3 dB)
Settling time	200 µs
Rise time/fall time	20 µs
Galvanic isolation
Output/power supply	functional insulation, rated insulation voltage 50 V AC
Output/Output	functional insulation, rated insulation voltage 50 V AC
Indicators/settings
Display elements	LED
Labeling	space for labeling at the front
Directive conformity
Electromagnetic compatibility
Directive 2014/30/EU	EN 61326-1:2013 (industrial locations)
Conformity
Electromagnetic compatibility	NE 21:2011
Degree of protection	IEC 60529:2001
Protection against electrical shock	UL 61010-1:2012
Ambient conditions
Ambient temperature	-20 ... 60 °C (-4 ... 140 °F)
Mechanical specifications
Degree of protection	IP20
Connection	screw terminals
Mass	approx. 200 g
Dimensions	20 x 124 x 115 mm (0.8 x 4.9 x 4.5 inch) , housing type B2
Mounting	on 35 mm DIN mounting rail acc. to EN 60715:2001
Data for application in connection with hazardous areas
EU-type examination certificate	BAS 99 ATEX 7025 X
Marking	II (1)G [Ex ia Ga] IIC ,  II (1)D [Ex ia Da] IIIC ,  I (M1) [Ex ia Ma] I
Input	[Ex ia Ga] IIC, [Ex ia Da] IIIC, [Ex ia Ma] I
Supply
Maximum safe voltage	250 V (Attention! The rated voltage can be lower.)
Equipment	terminals 1+, 3-
Voltage Uo	25.4 V
Current Io	86.8 mA
Power Po	551 mW
Equipment	terminals 2-, 3
Current Io/Current Ii	74 mA / 115 mA
Current Ii	115 mA
Voltage Uo	3.5 V
Current Io	74 mA
Power Po	64 mW
Equipment	terminals 1+, 2 / 3-
Voltage Ui	30 V
Current Ii	115 mA
Voltage Uo	25.4 V
Current Io	115 mA
Power Po	584 mW
Equipment	terminals 5-, 6+
Voltage Ui	30 V
Current Ii	115 mA
Voltage Uo	8.7 V
Current Io	0 mA
Output
Maximum safe voltage	250 V (Attention! The rated voltage can be lower.)
Certificate	TÜV 99 ATEX 1499 X
Marking	II 3G Ex nA II T4 [device in zone 2]
Galvanic isolation
Input/Output	safe electrical isolation acc. to IEC/EN 60079-11, voltage peak value 375 V
Input/power supply	safe electrical isolation acc. to IEC/EN 60079-11, voltage peak value 375 V
Directive conformity
Directive 2014/34/EU	EN 60079-0:2012+A11:2013 , EN 60079-11:2012 , EN 60079-15:2010
International approvals
UL approval
Control drawing	116-0428 (cULus)
IECEx approval	IECEx BAS 04.0015X
	IECEx CML 15.0055X
Approved for	[Ex ia Ga] IIC, [Ex ia Da] IIIC, [Ex ia Ma] I
	Ex nA IIC T4 Gc
General information
Supplementary information	Observe the certificates, declarations of conformity, instruction manuals, and manuals where applicable. For information see - www.control-automation.com/
Accessories
Optional accessories	- power feed module KFD2-EB2(.R4A.B)(.SP)
	- universal power rail UPR-03(-M)(-S)
	- profile rail K-DUCT-BU(-UPR-03)