Railway signals in China are based on OSShD signals[1] used by 25 countries of the former USSR, eastern Europe and adjacent countries.
[5] Apart from Red=Halt and single G=Clear, the lights of a semaphore signal at night do not match their colour light equivalents.
Colour lights: single green means full speed on straight, red means stop, with remainder meaning something in between.
If one of the green lamps fails, a less restrictive aspect is displayed which is potentially dangerous.
China is building or has built new standard gauge railways in Africa, and these are being built to Chinese standards, which in turn apply the standards of OSShD and other companies and businesses.