UK Whirlpool bath

[Tequila]

Whilrpool bath pump and heater have an earth lead attached to the metal casings. Should they just be joined together so potential of both casings is equal in event of a fault?

 

[brianmoooore]

They should be joined together, connected to the earth cable of the supply, and the supply protected by a 30mA or lower RCD.

 

[Tequila]

They should be joined together, connected to the earth cable of the supply, and the supply protected by a 30mA or lower RCD.

Hi thanks for that.. however the pump and heater are supplied with 3core flex so already earthed through their prospective supply cables? So other than connecting together for supplementary bond is there a need to connect to main supply earth?
I currently have split board cu protected by 30mA rcd, 20amp breaker feeding 13amp fcu outside bathroom with 4mm cable. I then have 2.5mm cable to underside of bath to ip55 jb supplying the 3 flex cables to pump heater class 1 and air pump which is class 2. Appreciate the information