Black Box Corporation
Black Box Corporation DNHSP387A USB Isolator 4 kV USB 1.1 3.3 ft
USB isolator provides 4 kV electrical protection between a PC and peripheral with 3.3 ft cable
- Protects PCs and USB peripherals from damaging electrical surges and EMI/RFI disturbances
- Powered directly from the USB port with no external supply needed
- Electrical isolation prevents disruptive ground loops in measurement applications
- Isolates up to 4 kV for hospital and medical-grade protection
- USB 1.1 compliant with 3.3 ft cable included
Isolated USB 1.1 Link
This one-port isolator sits between a computer and a USB peripheral to break ground loops and block surges up to 4 kV. It draws power from the host port so no external supply is needed. The device targets medical, industrial and measurement environments where electrical noise or fault currents threaten data integrity and hardware safety.
Steady-State Isolation Behaviour
The barrier maintains its 4 kV rating continuously rather than only during brief transients, so long monitoring sessions stay protected. Because the link runs at USB 1.1 speeds, sustained throughput remains modest and suits low-bandwidth sensors or legacy equipment. No active cooling is required and the isolator adds negligible latency to the data path.
Compact Inline Form Factor
A 3.3 ft captive cable keeps the isolator close to the host while the small body fits behind crowded equipment racks or on crowded benches. Standard Type-A connectors at both ends mean no adapters are necessary for typical PC and peripheral ports. The plug-and-play design requires no drivers, so technicians can insert or remove the unit without reconfiguring software.
Highlights
- Protects PCs and USB peripherals from damaging electrical surges and EMI/RFI disturbances
- Powered directly from the USB port with no external supply needed
- Electrical isolation prevents disruptive ground loops in measurement applications
- Isolates up to 4 kV for hospital and medical-grade protection
- USB 1.1 compliant with 3.3 ft cable included
Specifications
No published specifications for this item yet.
Questions about this item
Does the 4 kV isolation draw extra power from the USB port during all-day use?
The isolator is powered entirely from the USB port and requires no separate supply.
What must the host computer provide for the DNHSP387A to function?
A standard USB 1.1 port supplies both data and the power the isolator needs.
Will this isolator work with a legacy USB 1.1 peripheral I still use?
Yes, it is USB 1.1 compliant and passes the signal through without changing the protocol.
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