Fuses are rated by current - sure enough the manual says replace the 24V Fuse but it neglects to say the current rating.
There are 3 fuses on the circuit board - 2.5A / 1.6A / 0.5A and there'll be an external 3A fuse as well. The manual here...
https://letsfixit.co.uk/wp-content/uploads/ZB-7-27-HE-SYSTEM.pdf
Says...
Fuses
B Remove the connections covers. Refer to fig. 27,
28.
The fuses are located adjacent to the mains connector
block and connector ST18. Refer to fig. 4.
Fuse, item 312, is only replaceable by removing the
pcb.
Spare fuses are fixed to the connections cover.
A fuse pack is available: Part number 8 744 503 010 0.
Good Luck...
December 2016
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