ANR250-UL: A High-Voltage ATO/ATC Blade Fuse for 250VAC / 80VDC Systems
In the real world, the current rating (amps) is only half the story. When voltage increases the fuse has a harder job interrupting a fault without sustaining an arc. That’s why the voltage rating isn’t simply a “nice-to-have” on higher-voltage platforms, it’s part of what makes the protection system work when something actually fails.
OptiFuse ANR250-UL is built for exactly that gap: a familiar ATO/ATC (regular blade) footprint, but rated for 80VDC and 250VAC, with interruption ratings that address real fault events.
What the ANR250-UL is (and why it exists)
Most people think of ATO/ATC blade fuses as only 12V/24V automotive parts. ANR250-UL keeps the same serviceable blade format, but targets advanced electrical architectures, including systems that have higher voltage DC rails.
Key ratings at a glance:
- Voltage: 80VDC / 250VAC
- Breaking capacity: 1,000A @ 58VDC, 1,000 @ 80VDC, 400A @ 250VAC
- Amp range from 500mA through 40A
- Standards available: SAE J1284, SAE J2576, ISO 8820-3
OptiFuse’s ANR250-UL is the highest-voltage automotive blade fuse available in the market, delivering 250VAC / 80VDC performance in a familiar ATO/ATC footprint.
EV and hybrid applications
In EV and hybrid platforms, the strongest fit for the ANR250-UL is not the main traction bus, but the sub-80V auxiliary layer: especially 48V mild-hybrid and electrified support circuits.
As vehicle architectures add more 48V loads, designers may still want a compact, serviceable blade fuse format for branch protection where traditional 32V blade fuses are no longer the right voltage class. Typical examples include:
- Electric coolant pumps
- Electric oil pumps
- Electric vacuum pumps
- Radiator/condenser fan branches, and other 48V auxiliary motor or actuator circuits
Where ANR250-UL shows up in the field (not just “EV/hybrid”)
- Onboard chargers / auxiliary power modules that include AC sections needing compact, replaceable overcurrent protection.
- Vehicle HVAC subsystems and other onboard equipment where AC power exists upstream of conversion stages.
- 48V+ accessory distribution where the team wants to stay in a standard ATO/ATC service format, but the platform voltage exceeds “traditional” blade fuse ratings.
- Telecom / industrial DC loads where technicians prefer a quick visual ID + easy replacement (color coding stays standard across the blade family).
A popular pairing: ANR250-UL + CNU-03
For PCB-mounted or compact equipment designs, the CNU-03 is a strong companion product to the ANR250-UL. It gives engineers a way to mount a regular blade fuse into a board-level or compact assembly while keeping the fuse replaceable and easy to service.
It’s important to note that the CNU-03 is rated for up to 30A while the ANR250-UL series offers amperages up to 40A.
Pair it correctly: fuse + holder + block
A higher-voltage fuse only does its job if the rest of the hardware matches the application:
- Verify maximum system voltage (not just “48V nominal”)
- Use a holder/fuse block rated for the same voltage class
- Confirm the fuse’s interrupting rating is appropriate for the available fault current at that point in the system
For multi-circuit distribution in the ATO/ATC ecosystem, OptiFuse’s BLR-1212-G (80VDC) is one example of a fuse block designed for higher-voltage vehicle architectures, and it pairs naturally with higher-voltage blade fuses like the ANR series.
For more inquiries, contact OptiFuse at [email protected]. See our Fuse Selection Guide for complete context
Sebastian Castañeda is a circuit protection specialist and technical writer with application-focused experience in technical support and custom protection design. He contributes practical, application-driven insights to the OptiFuse Blog.