The USB2.0 standard usually recommends a length of up to 5m.

However, in reality, cables that exceed this length are sold by major manufacturers. (Generally speaking, it is said that there is no significant effect on communication speed up to about 10m).

In addition to simple extension cables, USB cables with repeater functionality are also available. These are also commonly referred to as active cables.

Multiple companies sell these products, but the product in the photo is Sanwa Supply Co., Ltd.’s KB-USB-R212 [12m extension USB active repeater cable].



According to USB cable standards, the maximum connection distance between devices is usually 5 meters. However, by using this “USB cable with repeater function”, you can connect devices with a cable longer than 5m. The product in the photo can be extended up to 12m using this cable.


This cable has a built-in signal amplification correction circuit. This circuit compensates for signal attenuation and allows cable extension. This cable can be extended over 12m. In that case, wire as shown below.



I tried connecting a 12m USB cable with repeater function (product in the photo) and the cable (1.8m) that came with the camera to our USB camera, and it worked without any problems. However, the instruction manual for the USB cable with repeater function (product in the photo) states, “To ensure stable operation and recognition, we recommend that the connected USB device be a self-powered device.” there was.

Of course, there are also active cables that use USB power (bus power). It is convenient and does not require a power supply, but if your PC’s power supply is weak, stability may be a problem.

Extending the USB cable will cause a voltage drop, so we recommend that you always check the operation when using devices that are powered by a PC (including our USB cameras).