Pepperl+Fuchs / Two Independent Transmitter Loops
KFD2-STC4-EX2 is a Pepperl+Fuchs SMART transmitter power supply for two field measurement channels. Unlike a one-input signal splitter, this arrangement serves two transmitter loops. This article organizes the selection around a loop budget and communication review, helping teams document the requirements before specifying a spare or expanding an analog cabinet.
Create one record per transmitter
Begin with separate records for channel one and channel two. Each should identify the transmitter, cable route, receiving analog input, and drawing revision. Then relate both records to the common module location. This preserves individual loop identities while giving maintenance a clear view of the two measurements associated with the same housing.
KFD2-STC4-EX2 electrical outline
The official specification lists two isolated channels for two-wire SMART transmitters, with 0/4 to 20 mA outputs. The published available field voltage is at least 16 V at 20 mA. Use that value within the full loop calculation. Also, check the permitted output load and the actual receiving input requirements.
Budget the voltage before choosing the spare
A transmitter needs enough voltage after the circuit losses are considered. Therefore, include cable resistance and any approved series components in the assessment. Review both loops independently, since their cable runs may differ. A calculation for the shorter route does not automatically establish adequate voltage for the second field point.
Make SMART access part of the handover
The unit provides test points, and the official documentation describes communication connections. First, identify where maintenance will connect its communicator. Then review the loop resistance and access arrangement for each channel. In addition, record the agreed method in the commissioning file so future technicians do not need to reconstruct the communication path.
State the procurement quantity clearly
- Name the two-wire transmitters and their channel tags.
- Give module quantities and identify any spare allocation.
- Include approval requirements, article number, and delivery destination.
The published safety capability is up to SIL 2 under manufacturer conditions. If an offer proposes a signal-splitting version instead, engineering should compare its topology explicitly before purchasing treats it as a suitable alternative.







