FCL FTR-K3 Series Power Relays: Simplifying PCB Track Routing

While finding a standard 16 A, 250 VAC power relay is never a challenge, your options shrink dramatically once your design pushes into the 20 A or 25 A territory at that same voltage. That is precisely where the FTR-K3 series from FCL Components (formerly Fujitsu) steps in to bridge the gap.

Contact protection and safe PCB clearance with the FTR-K3 series

"The FTR-K3 is an incredibly compact PCB power relay, but what really stands out is its clever pin layout. Specifically, this arrangement makes it effortless to maintain safe isolation distances on the contact side, leaving you with plenty of room to drop in the necessary protective components," says František Ďuríšek, Product Manager at SOS electronic.

The physical spacing between the coil and contact pins also ensures a reliable isolation barrier between your low-voltage control logic and the mains-voltage switching side. If you choose the "J B" variants, such as the FTR-K3 J B 024 W, they come equipped with 6,35 mm flat-tab terminals directly on the contact side. This hardware-level layout is incredibly practical as it allows you to populate the PCB with critical protective components like RC networks and varistors, whilst routing the heavy-duty switched load directly through the flat tabs. 

Another notable advantage for challenging designs is the power relay’s ability to withstand peak transient currents during switching of up to 200 A. On the control side, the coil options cover all standard industry rails from 5 VDC up to 48 VDC.

Pin layout and dimensions of the FTR-K3 series

Key features and specifications of the FTR-K3 series

• Optimised pin layout
• Compact footprint: 30,4 x 16,0 x 23,3 mm
• High contact current ratings of 20 A or 25 A
• Standard contact voltage rating of 250 VAC
• Robust peak inrush current tolerance of up to 200 A
• Nominal coil voltages ranging from 5 VDC to 48 VDC
• Certified under global safety standards including UL, CSA, VDE, CQC, and TUV

Versatile applications from industrial automation to smart homes

• Photovoltaics and solar inverters: Ideal for designs requiring strict compliance with the rigorous European VDE0126 standard for physical isolation. 
• Uninterruptible power supplies (UPS): Reliably handles the high-energy current spikes typical during rapid mode switching.
• Inverter loads and motor switching: Easily copes with massive initial startup inrush currents that would normally weld the contacts of standard, lighter-duty relays together.
• Industrial automation
• Smart home systems and appliances

We have officially added the FTR-K3 series to our permanent stock, so they are ready for immediate dispatch. If your project requires a different variant, we can easily source it for you on request. In the meantime, feel free to explore the full range of FCL Components relays on our website.

Try a sample for your project

Need to test a component during development? Don’t hesitate to get in touch, and we’ll be happy to provide a sample for your project. We review each request individually, so please share a brief overview of your project with us in the form below.

Note: Samples are provided for development projects only, not for individual personal use.

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