SIL 2 Certified Transmitter: ULCOS 900SIL

ULCOS 900SIL: JM Concept’s New Universal SIL 2 Certified Transmitter

In industrial process installations, some measurements play a role that goes far beyond simple process control. Temperature, pressure, level, or other critical variables can directly determine whether an installation must be brought to a safe state.

To meet the requirements of these applications, JM Concept is expanding its range with the ULCOS 900SIL, a universal signal converter/transmitter designed for functional safety loops.

Three models in the ULCOS 900 range are now SIL 2 certified in accordance with IEC 61508:2010:

• ULCOS 900D1SIL,
• ULCOS 920D0SIL,
• and ULCOS 920D2SIL.

This marks a new step for JM Concept, combining its long-standing expertise in industrial signal conditioning with the requirements of functional safety.

What is a SIL 2 safety loop?

In a process installation, not all measurements serve the same purpose.

Some are used to control and regulate the process. Others are designed to detect potentially hazardous conditions and trigger a safe shutdown, such as excessive temperature, overpressure, or a critical level.

These functions fall under functional safety.

They are governed in particular by the international IEC 61508 standard, which defines different safety integrity levels known as SIL — Safety Integrity Level.

For a safety loop to achieve the required SIL level, each of its components — sensor, signal conditioner, and safety instrumented system — must meet the corresponding requirements.

Located between the field sensor and the safety system, signal conditioning is therefore a key link in the safety chain.

ULCOS 900SIL: Isolate, Measure, Convert, and Transmit Safely

This is precisely the role of the new ULCOS 900SIL.

Mounted on a DIN rail, this converter/transmitter conditions the signal between the field sensor and the safety instrumented system.

It isolates, measures, converts, and transmits the acquired variable, while continuously monitoring its own operation.

If a fault is detected, the device switches to a predefined safe state: the relay returns to its de-energized position and the analog outputs are forced to 0 mA / 0 V.

The safety system therefore receives an unambiguous indication of the situation and can trigger the required safety action.

Three SIL 2 Certified Transmitters in Accordance with IEC 61508

The certification covers three models in the range:

• ULCOS 900D1SIL, dedicated to safety-related analog measurement;
• ULCOS 920D0SIL, dedicated to relay alarm functions when a threshold is exceeded;
• ULCOS 920D2SIL, combining both safety functions in a single device.

The certification therefore covers two separate safety functions.

SF1 — Analog measurement: the device provides a 4–20 mA or 1–10 V output proportional to the variable measured by the connected sensor.

SF2 — Threshold alarm: the device provides a digital relay output when a configurable threshold is crossed.

The ULCOS 920D2SIL therefore combines safety-related analog measurement and a safety relay alarm in a single 17.5 mm-wide housing, with no additional module required.

Comprehensive SIL 2 Certification

All three models are SIL 2 certified in accordance with IEC 61508:2010, Parts 1 through 3.

The assessment covers both systematic capability, including product design and control of systematic failures, and the device’s hardware safety integrity.

Certification was issued by BYHON, an accredited third-party organization. Certificate JMCO-ULCOS-ESE-A01, issued on June 26, 2026, covers all three models through June 25, 2029.

The ULCOS 900SIL is a Type B component, with SC 2 systematic capability and an architecture with no hardware fault tolerance (HFT = 0), suitable for applications up to SIL 2.

Diagnostic coverage (DC) reaches 90.5% for the 4–20 mA analog output.

Universal Input for Simpler Safety Loops

One of the main advantages of the ULCOS 900SIL is its universal input.

A single model can accept a wide range of signals and sensors, including:

• current;
• voltage;
• thermocouples;
• Pt100 and Pt1000 RTDs, 2- or 3-wire;
• resistance;
• potentiometers;
• NTC/PTC sensor tables.

This flexibility allows a wide range of measurements to be handled by a single device and helps reduce the number of product references required for installations and maintenance inventories.

Two Safety Functions in Just 17.5 mm

Available cabinet space is often a major constraint in industrial installations.

With the ULCOS 920D2SIL, JM Concept combines a universal input, a safety-related analog measurement function, and a safety relay alarm in a housing only 17.5 mm wide.

There is therefore no need to add multiple modules to perform these functions.

This is particularly useful when designing compact control cabinets, as well as when upgrading or modernizing existing installations.

Universal Power Supply, Even in SIL Mode

Another key feature is that the ULCOS 900SIL retains its universal power supply when the safety function is active.

The device accepts:

90 to 230 Vac / 22 to 240 Vdc.

In an existing cabinet already supplied with 230 Vac, for example, the device can therefore be integrated without adding a dedicated 24 Vdc power supply.

This makes it particularly well suited to retrofit projects.

Up to 4200 Vrms Galvanic Isolation

Galvanic isolation lies at the heart of JM Concept’s historical expertise.

The ULCOS 900SIL provides reinforced isolation of up to 4200 Vrms between the power supply and inputs/outputs, as well as 2500 Vrms between input and output, at 50 Hz for one minute.

This isolation helps protect the different devices within the loop and maintain signal integrity in demanding industrial environments.

Response Time Below 150 ms

In a safety loop, the time required to transmit critical information can be a key design parameter.

The ULCOS 900SIL provides a response time of less than 150 ms for process, thermocouple, and resistance inputs, and 300 ms for RTD and potentiometer inputs.

These performance levels are maintained when the safety function is active.

Two Independent Analog Outputs

The device can also provide a 4–20 mA output and a 1–10 V output simultaneously and independently, both covered by the SIL 2 certification.

A single transmitter can therefore send, for example, a current signal to the safety instrumented system while simultaneously sending a voltage signal to a PLC or recorder.

Both outputs are isolated from the rest of the circuit, although they are not isolated from each other.

Front-Panel Configuration

Despite its advanced functionality, configuration remains simple.

The ULCOS 900SIL is configured directly from the front panel using an integrated joystick and LCD display.

The various parameters can therefore be set directly on the device during commissioning.

What Applications Is the ULCOS 900SIL Designed For?

The ULCOS 900SIL was developed for safety loops in industrial process installations on the European market.

It can meet requirements in sectors including:

• water treatment;
• power generation;
• chemical processing;
• food and beverage;
• and, more broadly, process industries requiring the monitoring of critical levels, pressures, temperatures, or other process variables.

It is particularly well suited to single-channel safety loops, applications requiring both measurement and alarm functions for the same process variable, and retrofit projects involving existing cabinets powered by 230 Vac.

Its operating temperature range is -10°C to +60°C.

10-Year Mission Time

The safety data provided for each configuration includes failure rates and diagnostic coverage.

The ULCOS 900SIL is designed for a 10-year mission time, with a maximum proof test interval of 5 years.

As with any device integrated into a safety instrumented function, implementation must be carried out by professionals with the appropriate expertise in functional safety and IEC 61508, in accordance with the manufacturer’s requirements for installation, commissioning, operation, and maintenance.

ULCOS 900SIL: Functional Safety Built on JM Concept Expertise

Since 1992, JM Concept has built its expertise around four essential functions: isolating, measuring, converting, and transmitting industrial signals.

With the SIL 2 certification of three models in the ULCOS 900 range, this expertise now extends to functional safety loops in industrial process installations.

Universal input, two safety functions in a 17.5 mm housing, universal power supply, reinforced galvanic isolation, and controlled response times: the ULCOS 900SIL has been designed to combine functional safety, ease of integration, and performance.

Designed and manufactured in France at JM Concept’s facility in Brignais, near Lyon, these new transmitters build on more than 30 years of expertise in industrial signal conditioning.

Do you have a project involving SIL 2 safety loops? Contact the JM Concept team to identify the solution best suited to your application.