RCD UPSIDE DOWN ?

The general standard for this is BS EN 60447 Basic and safety principles for man-machine interface, marking and identification — Actuating principles. According to this standard, the direction “UP” means “start machine” or “close electrical circuit”, and “DOWN” means “stop machine" or “open electrical circuit” (Normative Annex A, Tables A.1 and A.2) 

Note, however, that it is a basic safety standard for use by standards committees, and is probably more aligned with considerations for machinery, and where an innate haptic meaning may be more appropriate.

In general, there is no convention specifically mandated in standards for electrical protective devices and isolators, because it is recognised that devices may be installed in different orientations if this is not precluded by the manufacturer. For example, product standards for these kinds devices have the following requirements:

• BS EN 60898, BS EN 61008 and BS EN 61009 simply require the open position and closed positions to be clearly indicated by ‘O' and ‘I’ respectively. Of course this is not required for mcb's, RCDs or RCBO's that use a push-button “set/reset” type arrangement.
   
• BS EN 60947-1 says that whilst generally the operation of actuators should conform to IEC 60447 (BS EN 60447), where devices may be used in special applications or alternative mounting positions they should be clearly marked such there is no doubt as to the ‘I’ and ‘O’ positions, and the direction of operation.

We certainly ignore BS EN 60447 with general-purpose light switches and many “domestic” controls. One suggestion I've heard offered for this is perhaps  it's easier to “fumble” a light switch switch into the “on” position in the dark, if “down” is “on”.

The general standard for this is BS EN 60447 Basic and safety principles for man-machine interface, marking and identification — Actuating principles. According to this standard, the direction “UP” means “start machine” or “close electrical circuit”, and “DOWN” means “stop machine" or “open electrical circuit” (Normative Annex A, Tables A.1 and A.2) 

Note, however, that it is a basic safety standard for use by standards committees, and is probably more aligned with considerations for machinery, and where an innate haptic meaning may be more appropriate.

In general, there is no convention specifically mandated in standards for electrical protective devices and isolators, because it is recognised that devices may be installed in different orientations if this is not precluded by the manufacturer. For example, product standards for these kinds devices have the following requirements:

• BS EN 60898, BS EN 61008 and BS EN 61009 simply require the open position and closed positions to be clearly indicated by ‘O' and ‘I’ respectively. Of course this is not required for mcb's, RCDs or RCBO's that use a push-button “set/reset” type arrangement.
   
• BS EN 60947-1 says that whilst generally the operation of actuators should conform to IEC 60447 (BS EN 60447), where devices may be used in special applications or alternative mounting positions they should be clearly marked such there is no doubt as to the ‘I’ and ‘O’ positions, and the direction of operation.

We certainly ignore BS EN 60447 with general-purpose light switches and many “domestic” controls. One suggestion I've heard offered for this is perhaps  it's easier to “fumble” a light switch switch into the “on” position in the dark, if “down” is “on”.