The FireFly® system is composed of three main internal components:

• Floating Probe Head
• Grounded Interface Box (IB)
• Fiber-Optic Cable (connecting IB and Probe Head)

Floating Probe Head (Measurement Point)

At the heart of the system, you have the floating probe head. This carefully designed probe head is the physical measurement device touching your circuit or device under test (DUT). It is called “floating” because it’s fully galvanically isolated from ground or earth potential, ensuring your measurements are not contaminated by common-mode interference or noise.

The probe head collects measurement signals directly from the DUT, ensuring precise, interference-free data acquisition even in high-voltage and noisy environments.

Grounded Interface Box (IB)

Next in the chain is the Interface Box (IB). The IB is your connection hub—it remains grounded, acting as the primary interface between your FireFly® probe and external instruments (oscilloscope and power supply). The IB serves several important functions:

• Signal transmission: Transmits measured signals via a standard BNC cable directly into your oscilloscope.
• Power provision: Receives power from the external PMK power supply through a robust, easy-to-use Lemo connector.
• Control & functionality: Offers features like "auto-zero," status indicators, and remote control capability.

The IB ensures stability, reliability, and user convenience throughout the measurement process.

Fiber-Optic Cable (Galvanic Isolation)

The fiber-optic cable permanently connects the floating probe head and the IB into an inseparable unit. Fiber-optic technology is the key to achieving complete galvanic isolation, ensuring the integrity of your measurements:

• Electrical isolation: Completely isolates the probe head from the IB and any downstream electronics.
• Noise immunity: Guarantees no electrical interference affects your measurement data.
• Safety: Ensures the operator and sensitive measurement equipment remain safe from high-voltage potentials.

In the diagram, the fiber-optic connection is indicated by red lines, clearly marking the galvanically isolated segments.

Connecting the FireFly® System to the Oscilloscope and Power Supply

Now let’s discuss the connections clearly illustrated in the provided diagram.

Connection to Oscilloscope (Signal Output):

• A standard BNC connector cable links directly from the IB to your oscilloscope.
• Your oscilloscope remains connected to earth potential and directly powered by the grid.

This straightforward connection allows immediate, reliable transfer of precise measurement signals to your oscilloscope display.

Connection to PMK Power Supply:

• The Lemo-type connector cable connects from the IB to the external PMK power supply.
• The power supply unit, also grid-connected, ensures consistent, reliable power for stable measurement operations.

PMK offers different models (PS02/PS03) for flexible laboratory integration, including remote control capabilities through USB and optional LAN connectivity.

Understanding Galvanic Isolation (Red Lines):

In the provided diagram, you'll notice certain cables marked in red lines. These red lines indicate components and segments fully galvanically isolated:

• Fiber-optic cable connecting IB and floating probe head.
• Floating probe head itself, isolated from ground and power supply.

Thanks to fiber-optic technology, this isolation ensures measurements are interference-free, extremely accurate, and safe even under high-voltage testing conditions.

Simplifying Your Measurement Workflow

The FireFly® system’s unique structure makes high-voltage testing straightforward, safe, and precise:

• Plug-and-play setup to your oscilloscope via standard BNC connectors.
• Reliable, isolated power delivery through specialized PMK power supplies.
• Simple operational controls located conveniently on the IB.
• Unmatched signal integrity and operator safety through fiber-optic isolation.

Ready to Learn More or Request a Demonstration?

If you have questions about integrating the FireFly® system into your measurement setup or would like more information, please contact our sales teams:

• Europe and International: sales@pmk.de
• Americas: sales@pmkamerica.com

Your PMK Probing Solutions Team