Brother HL-5150D - Manual (Page 134)

B - 5 APPENDIX (FOR EUROPE AND OTHER COUNTRIES)
Wiring information (for UK)
Important
If you need to replace the plug fuse, fit a fuse that is approved by ASTA to BS1362 with the same rating
as the original fuse.
Always replace the fuse cover. Never use a plug that does not have a cover.
Warning - This printer must be earthed.
The wires in the mains lead are coloured in line with the following code:
Green and Yellow: Earth
Blue: Neutral
Brown: Live
If in any doubt, call a qualified electrician.