I have an SSD named IID, a MBP-tp (MacBook Pro touch-pad), Anker6 (externally powered Anker 6 port USB3 hub), Anker9 (externally powered Anker 9 port USB3 hub), a Yafeite hub with two male USB-C connectors, one female USB-C port and two USB-3A female ports.
Usually the two Ankers occupy the two USB-3A ports on the Yafeite hub, which itself connects to two USB-C female ports on the left side of the MBP-tp.
The SSD IID is in an Inatek FE 2007 USB3 enclosure/hub. The Inatek device works flawlessly if directly connected to a USB-C port on the MBP-tp, or to a USB-3A port on the Yafeite hub.
But (!) when connect to the Anker9, it does not mount. Enter the Klein Tools USB tester ET920 (essentially a digital voltmeter/ammeter). when the Inatek is connected to Anker9 via the USB tester, the tester shows 4V, so no wonder it does not work. When the Inateck is connected to to Anker6, it appears not to work, but when the tester is interposed, I see about 5V and about 0.5 A, and (!) the device mounts. I have tried changing USB cables, but this makes no difference
How could the interposition of the test device make such a difference? The test device is too expensive to allocate one to each self-powered USB enclosure. Connecting transformers (power supplies) to each nominally but not actually self-powered inclosure is tedious in a complex multi-volume system.
I can see that I might need a higher voltage (greater wattage) power supply for the Anker9, but what is going on with the Anker6 and the test device?
Usually the two Ankers occupy the two USB-3A ports on the Yafeite hub, which itself connects to two USB-C female ports on the left side of the MBP-tp.
The SSD IID is in an Inatek FE 2007 USB3 enclosure/hub. The Inatek device works flawlessly if directly connected to a USB-C port on the MBP-tp, or to a USB-3A port on the Yafeite hub.
But (!) when connect to the Anker9, it does not mount. Enter the Klein Tools USB tester ET920 (essentially a digital voltmeter/ammeter). when the Inatek is connected to Anker9 via the USB tester, the tester shows 4V, so no wonder it does not work. When the Inateck is connected to to Anker6, it appears not to work, but when the tester is interposed, I see about 5V and about 0.5 A, and (!) the device mounts. I have tried changing USB cables, but this makes no difference
How could the interposition of the test device make such a difference? The test device is too expensive to allocate one to each self-powered USB enclosure. Connecting transformers (power supplies) to each nominally but not actually self-powered inclosure is tedious in a complex multi-volume system.
I can see that I might need a higher voltage (greater wattage) power supply for the Anker9, but what is going on with the Anker6 and the test device?