Technical FAQs

Ask a Question

Are there any restrictions regarding the installation mounting orientation of Square D Heavy Duty, General Duty and Double Throw Safety Switches?

Issue:
Product Design 

Product Line:
Heavy Duty, General Duty and Double Throw Safety Switches

Environment:
Product Mounting outside of Vertical ONLY

Cause:
Application

Resolution:
ALL NEMA Type Square D Safety Switches are UL tested in an upright (vertical) position ONLY, with the 'ON' in the up position of the switch. Safety switches also have different NEMA type enclosures that could pertain to installation and mounting restrictions in different environments. The following could be some of these mounting orientations:
1) Horizontal mounting(or lying on it's back) is subject to the permission of the local code authority. In addition, the National Electrical Code(NEC) prohibits the safety switches from being mounted on their back, so that gravity will act on the blades not to 'Close' them.

2)
 Mounted at an angle(maybe on a roof top) is again subject to the permission of the local code authority. In addition, the NEC may have restrictions that prohibit the safety switch from being mounted at an angle of any degree, especially NEMA 3R or other Outdoor NEMA rated switches, due to water entering.

3) Mounted 'Upside down'. This orientation would be considered a violation of the NEC, see specific article that requires the operating handle of a disconnect to have the 'ON' in the up position.

4) Mounted 'Flat' on the back of the enclosure. This orientation would also be considered a violation of the NEC, again see specific artilces in the NEC that might speak to this orientation. 


NOTE: There are no known objections to mounting a NEMA 1 switch on its side, BUT again, this is dependent upon interpretation of the local code authority. Consideration should always be given to allow full movement of the operating handle and front cover. NEMA 3R switches should always be installed in the upright position.


CTA-ID : 2007997
Was this helpful?
What can we do to improve the information ?