This light takes 9x10Watt Halogen bulbs.I had put in
9x20Watt bulbs by mistake,the light continued to work for a while but now won't work at all.No switches were tripped in main fuse box.I have looked inside light but there is nothing obvious that has blown.
These are probably low voltage lamps driven from a transformer - your original power consumption was 90W but you temporarily increased it to 180W - not enough to bother the breaker in the consumer unit but probably plenty enough to destroy the transformer supplying the low voltage lamps. It will have got very hot inside and a wire may have melted - likely you need a replacement transformer - Wattage is the key rating for any replacement.