Unexpected problem

I use an SSD for the photographs of the current year, and then copy the contents to a conventional disc at the end of the year and clear the space on the SSD (actually I copy the contents daily rather than waiting until the end of the year!). Today I discovered a problem which I have not encountered before. I usually use my Surface 3 Pro computer in a docking station, and connect the drive via the docking station. However, today I plugged the SSD into the Surface Pro 3 without using the docking station, though I was using mains power. The Surface refuses to recognise the SSD. I can only assume this is because the SSD tries to draw more current from the Surface than it is able to provide. But plugging in a conventional spinning disc, also powered direct from the USB port on the Surface is fine. So perhaps surprisingly the SSD drive, with no moving parts, seems to draw more current than one (larger capacity) with a spinning disc.