KCD2-SCS-Ex2.SP Pepperl+Fuchs SMART Transmitter Power Supply 2 Channel Isolated Intrinsic Safety Barrier
Product Overview
The KCD2-SCS-Ex2.SP is a versatile 2-channel isolated barrier from Pepperl+Fuchs' K-System, specifically engineered for intrinsic safety applications requiring either analog input or analog output functionality. Each channel can be independently configured as a transmitter power supply (powering 2-wire SMART transmitters) or a current driver (driving SMART I/P converters and positioners).
With a compact 12.5 mm width and 24 V DC power supply (via Power Rail or terminals), this device provides complete galvanic isolation between field and control circuits while supporting bidirectional SMART communication for intelligent field device configuration and diagnostics.
Certified for SIL 2 (SC 3) acc. to IEC/EN 61508 and approved for hazardous area installation with [Ex ia Ga] IIC certification, the KCD2-SCS-Ex2.SP is the ideal solution for analog signal transfer in safety-related and explosive atmosphere applications.
Model Number Decoding
| Code Segment |
Meaning |
| KCD2 |
K-System, 2-channel housing width (12.5 mm) |
| SCS |
SMART Current / Voltage Signal — configurable as transmitter power supply or current driver |
| Ex2 |
2-channel with intrinsic safety (Ex) certification |
| .SP |
Spring terminals (push-in connection technology) |
The ".SP" suffix denotes spring terminal version with push-in connection for fast, vibration-proof wiring.
Key Features & Benefits
- Dual-Function per Channel: Each channel can be configured via DIP switches as either a transmitter power supply (for 2-wire SMART transmitters) or a current driver (for SMART I/P converters, positioners, and displays) — providing maximum application flexibility
- Bidirectional SMART Communication: Supports digital communication for SMART devices using current modulation to transmit data and voltage modulation to receive data — enabling full HART configuration and diagnostics through the isolation barrier
- 2-Channel Efficiency: Two independent channels in a single 12.5 mm housing — maximizes panel space efficiency and reduces installation costs
- Intrinsic Safety Certification: ATEX and IECEx certified with [Ex ia Ga] IIC marking for installation in Zone 0, 1, and 2 hazardous areas (gas groups IIC, IIB, IIA)
- SIL 2 Certified: Safety Integrity Level 2 (SC 3) acc. to IEC/EN 61508 — suitable for safety-related applications up to SIL 2
- High Drive Capability: Transmitter power supply mode provides ≥15 V at 20 mA; Current driver mode drives loads up to 650 Ω with ≥13 V at 20 mA
- Line Fault Detection: In current driver operation, an open field circuit presents high impedance (>100 kΩ) to the control side, allowing lead breakage to be monitored by control systems
- Spring Terminal Connection: Push-in connection technology provides fast, vibration-proof, and maintenance-free wiring
- Power Rail Compatibility: Connects to Pepperl+Fuchs Power Rail for simplified daisy-chained power distribution
- Wide Operating Temperature: Functions reliably from -40°C to +70°C, suitable for harsh industrial environments
- LED Status Indicators: Visual indication of channel status and power supply — simplifies troubleshooting
Technical Specifications
General Specifications
| Parameter |
Value |
| Manufacturer |
Pepperl+Fuchs SE |
| Product Type |
SMART Transmitter Power Supply / SMART Current Driver |
| Model |
KCD2-SCS-Ex2.SP |
| Signal Type |
Analog input / Analog output (configurable per channel) |
| Channels |
2 |
Functional Safety
| Parameter |
Value |
| Safety Integrity Level (SIL) |
SIL 2 |
| Systematic Capability (SC) |
SC 3 |
Supply
| Parameter |
Value |
| Connection |
Power Rail or terminals 9+, 10- |
| Rated Voltage |
19 ... 30 V DC |
| Ripple |
≤ 10 % |
| Rated Current |
≤ 88 mA at 24 V |
| Power Dissipation |
≤ 1.4 W |
| Power Consumption |
≤ 2.1 W |
Analog Input Mode (Transmitter Power Supply)
| Parameter |
Value |
| Suitable Field Devices |
2-wire SMART transmitters |
| Signal |
0/4 ... 20 mA, limited to approx. 30 mA |
| Field Circuit Terminals |
1+, 2- (Ch1); 3+, 4- (Ch2) |
| Available Voltage |
min. 15 V at 20 mA; min. 18 V at 4 mA |
| Control Circuit Terminals |
5-, 6+ (Ch1); 7-, 8+ (Ch2) |
| Load |
max. 350 Ω (source output) |
Analog Output Mode (Current Driver)
| Parameter |
Value |
| Suitable Field Devices |
SMART I/P converters (positioners), on-site displays |
| Signal |
0/4 ... 20 mA, limited to approx. 30 mA |
| Field Circuit Terminals |
1+, 2- (Ch1); 3+, 4- (Ch2) |
| Load |
max. 650 Ω |
| Voltage |
min. 13 V at 20 mA |
| Control Circuit Terminals |
5-, 6+ (Ch1); 7-, 8+ (Ch2) |
| Voltage Drop |
max. 6 V |
| Line Fault Detection |
>100 kΩ at max. 30 V, with field wiring open |
Transfer Characteristics
| Parameter |
Value |
| Deviation |
max. 20 µA (incl. calibration, linearity, hysteresis, loads, supply fluctuations) |
| Temperature Influence |
<2 µA/K (-40 ... 70°C) |
| Frequency Range |
0 ... 3 kHz (-3 dB) |
| Settling Time |
max. 200 ms |
| Rise/Fall Time |
max. 100 ms (10 ... 90%) |
Galvanic Isolation
| Parameter |
Value |
| Field Circuit/Control Circuit |
basic insulation, 300 Veff |
| Field Circuit/Power Supply |
reinforced insulation, 300 Veff |
| Control Circuit/Power Supply |
basic insulation, 300 Veff |
| Control Circuit/Control Circuit |
functional isolation, 50 V |
Hazardous Area Specifications (Ex ia)
| Parameter |
Value |
| Marking |
II (1)G [Ex ia Ga] IIC |
| Output Voltage (Uo) |
25.2 V |
| Output Current (Io) |
100 mA |
| Output Power (Po) |
630 mW |
| Internal Capacitance (Ci) |
1.05 nF |
| Internal Inductance (Li) |
0 |
Ambient Conditions
| Parameter |
Value |
| Ambient Temperature |
-40 ... 70 °C (-40 ... 158 °F) |
Mechanical Specifications
| Parameter |
Value |
| Degree of Protection |
IP20 |
| Connection |
Spring terminals (push-in technology) |
| Mass |
approx. 115 g |
| Dimensions (W x H x D) |
12.5 x 124 x 114 mm (0.5 x 4.9 x 4.5 inch) |
| Housing Type |
A2 |
| Mounting |
35 mm DIN mounting rail acc. to EN 60715:2001 |
Function Description
The KCD2-SCS-Ex2.SP is a configurable isolated barrier for intrinsic safety applications. Each of the two channels can operate independently in either mode:
Mode 1: Transmitter Power Supply (Analog Input)
- Powers 2-wire SMART transmitters located in hazardous areas
- Transfers the 4...20 mA measurement signal from the field to the control system
- Provides bidirectional HART communication for transmitter configuration and diagnostics
- Minimum available voltage: 15 V at 20 mA ensures reliable transmitter operation
Mode 2: Current Driver (Analog Output)
- Drives SMART I/P converters, valve positioners, and displays in hazardous areas
- Repeats the 4...20 mA control signal from the PLC/DCS to the field device
- Supports bidirectional HART communication for positioner configuration and feedback
- Drives loads up to 650 Ω with ≥13 V at 20 mA
- Line fault detection identifies open field circuits for control system monitoring
Signal Flow
Analog Input Mode (Transmitter Power Supply):
Hazardous Area Safe Area
2-wire SMART Transmitter ──► KCD2-SCS-Ex2.SP ──► 4...20 mA to PLC/DCS
◄── (Bidirectional HART) ◄── HART Communicator
Analog Output Mode (Current Driver):
Safe Area Hazardous Area
PLC/DCS 4...20 mA ──► KCD2-SCS-Ex2.SP ──► 4...20 mA to SMART I/P
HART Communicator ◄── (Bidirectional HART) ◄── Positioner/Valve
Applications
The KCD2-SCS-Ex2.SP is specifically designed for analog signal transfer in hazardous area installations:
| Industry |
Application |
| Oil & Gas |
Powering pressure/temperature transmitters on offshore platforms; driving I/P converters for pipeline control valves in Zone 1 areas |
| Chemical Processing |
Isolated analog input for reactor monitoring; analog output for chemical dosing valve positioning in explosive atmospheres |
| Pharmaceutical |
SIL 2 certified signal transfer for safety-related batch control; solvent handling equipment with Ex ia protection |
| Power Generation |
Transmitter power supply for gas turbine monitoring; current driver for boiler feedwater control valves |
| Water/Wastewater |
Pump station instrumentation in potentially explosive environments (digester gas areas) |
Typical Field Devices Connected
- 2-wire SMART pressure, temperature, level, flow, and pH transmitters (Analog Input mode)
- SMART I/P converters for pneumatic valve positioning (Analog Output mode)
- SMART valve positioners with HART communication (Analog Output mode)
- Field-mounted displays with 4...20 mA input (Analog Output mode)
Why Choose the KCD2-SCS-Ex2.SP?
- Dual-Function Flexibility — Unlike dedicated devices that only perform one function, the KCD2-SCS-Ex2.SP allows each channel to be independently configured as either a transmitter power supply or a current driver. This reduces spare parts inventory and simplifies engineering.
- Complete Intrinsic Safety Package — Certified with [Ex ia Ga] IIC for Zone 0, 1, and 2 hazardous areas, the device provides the highest level of intrinsic safety protection for gas groups IIC (hydrogen, acetylene), IIB, and IIA.
- SIL 2 Certified for Safety Applications — Certified acc. to IEC/EN 61508 with Systematic Capability SC 3, the KCD2-SCS-Ex2.SP is suitable for use in safety instrumented systems (SIS) up to SIL 2.
- Bidirectional SMART Communication — Full HART transparency allows digital configuration, calibration, and diagnostics of SMART field devices directly through the isolation barrier — no additional hardware required.
- Space-Saving Design — At just 12.5 mm width, the KCD2-SCS-Ex2.SP provides two complete analog signal channels in a compact footprint, maximizing DIN rail density.
- High Drive Capability — The current driver mode delivers ≥13 V at 20 mA into 650 Ω loads, providing sufficient power for demanding positioners and long cable runs.
- Fast, Reliable Wiring — Spring terminal technology with push-in connection provides vibration-proof, maintenance-free wiring that significantly reduces installation time.
- Proven Pepperl+Fuchs K-System — The K-System is the industry standard for signal conditioning and isolation, trusted globally for reliability, quality, and long service life.
Compliance & Certifications
| Certification |
Status |
Details |
| ATEX |
✅ Certified |
UL 22 ATEX 2786X — II (1)G [Ex ia Ga] IIC |
| ATEX Zone 2 |
✅ Certified |
UL 22 ATEX 2787X — II 3G Ex ec IIC T4 Gc |
| IECEx |
✅ Certified |
IECEx ULD 22.0020X — [Ex ia Ga] IIC |
| SIL 2 |
✅ Certified |
IEC/EN 61508, SC 3 |
| UL/cULus |
✅ Listed |
E106378, Control Drawing 116-0490 |
| CCC Ex |
✅ Certified |
China SITIIAS Certificate |
| DNV Marine |
✅ Approved |
TAA00001WX |
| UKEX |
✅ Certified |
UL22UKEX2497X |
| RoHS |
✅ Compliant |
Lead-free |