Pepperl+Fuchs KFD2-CRG2-1.D Transmitter Power Supply with Relays

KFD2-CRG2-1.D transmitter power supply with display and two alarm relays

The KFD2-CRG2-1.D powers a 2-wire or 3-wire transmitter, or accepts a 4-20 mA current source, and gives the control system an isolated current output together with two relay alarm contacts. A display shows the measurement in engineering units and a keypad lets the operator scale and configure the module. A linearization function with up to 20 points corrects non-linear signals, such as a level that has to be converted to volume in a tank.

Seven Star LLC supplies the KFD2-CRG2-1.D in Oman and the GCC as an independent supplier in Muscat. The sections below explain the design, the limits and the points to check before ordering.

KFD2-CRG2-1.D type code

The KFD2-CRG2-1.D is a type designation of the Pepperl+Fuchs K-System, named in the datasheet as a transmitter power supply, a 1-channel signal conditioner with 24 V DC supply through the Power Rail. The housing is 40 mm wide because it holds two relays and a display.

Programmable high and low alarms, adjustable energized and de-energized delays of 0 to 250 seconds and line fault detection distinguish this module from the plain STC5 supplies, which have no relays or display.

Technical specifications of the KFD2-CRG2-1.D

How the KFD2-CRG2-1.D works

The module supplies the connected transmitter with at least 15 V at 20 mA, measures the loop current across its 45 Ω input resistance and monitors the loop. Breakage below 0.2 mA and short-circuit above 22 mA are detected. The measured value is digitized and processed with the user scaling and, if required, the linearization table, then output as an active 0/4 to 20 mA signal and compared with the alarm thresholds.

Relay outputs follow the alarm logic with adjustable delays, and the datasheet states that both the relay contacts and the current output can be integrated into safety-relevant circuits. Faults are signalled by LEDs and a separate collective error message output on the Power Rail.

Compared with using a transmitter supply and an external alarm unit, the combination removes one device and one set of wiring, and it keeps the displayed value, the analog output and the alarms consistent because they come from the same measurement.

Positioning the KFD2-CRG2-1.D

Choose the KFD2-CRG2-1.D when a local indication and alarm point is needed together with loop power, for example at a tank level transmitter that also has to trip a pump. The KFD2-STC5-1 is the better choice when HART communication and the lowest cost per loop are required, because it is narrower and focuses on the SMART function.

It shares the Power Rail and power feed accessories with the KFD2-USC-1.D, KFD2-GUT-1.D and KFD2-UFC-1.D.

Selection and ordering checklist for the KFD2-CRG2-1.D

• Transmitter type and loop current range
• Scaling, units and whether linearization is needed
• Alarm limits, hysteresis and delays for the two relays
• Output range 0 to 20 mA or 4 to 20 mA
• SIL requirement and safety documentation
• Supply, rail arrangement and ambient limit

Configuring and maintaining the KFD2-CRG2-1.D

After wiring terminals 1 to 3 for the transmitter and the output and relay terminals, enter the scaling, units and alarm thresholds with the keypad or PACTware. For a tank with a non-linear geometry, enter the linearization points from the tank table. Verify each relay with a simulated input and write down the final parameters.

Maintenance consists of periodic loop verification. Because the module has no user serviceable parts, replace it as a unit and reload the saved configuration.

Typical applications in Oman and the GCC

Transmitter supplies with alarm relays are used on storage tanks, sumps, pressure vessels and header lines in oil and gas, water and power plants, where a local alarm is wanted without involving the DCS. Linearization is particularly useful for horizontal or conical tanks.

Transmitter supplies compared

Based on the datasheets.

Information to send with an RFQ for the KFD2-CRG2-1.D

Send these items for a quotation.

• Transmitter model and loop range
• Alarm setpoints and delays
• Linearization requirement
• Quantity and delivery date

Documents and quotation

The manufacturer datasheet for the KFD2-CRG2-1.D is attached on this page, so the electrical data, terminal assignment and ambient limits quoted above can be checked against the original document before an order is placed.

Seven Star LLC supplies Pepperl+Fuchs products in Oman and the GCC as an independent supplier in Muscat. Send the quantity, the signal types and the project delivery date, and we will confirm availability and lead time in a written quotation.