REGULATIONS

Following are references and excerpts from Fedral and Foreign Regulations that have applicability to Pushbutton Switches.

  • 29 CFR 1910.217 (b) (6) (i)

"A two hand trip shall have the individual operator's hand controls protected against unintentional operation and have the individual operator's hand controls arranged by design and construction and/or seperation to require the use of both hands to trip the press and use a control arrangement requiring concurrent operation of the individual operator's hand control."

  • 29 CFR 1910.217 (b) (7) (ii)

"A red color stop control shall be provided with the clutch/brake control system. Momentary operation of the stop control shall immeadiatly deactivate the clutch and apply the brake. The stop control shall override any other control, and reactuation of the clutch shall require use of the operating (tripping) means which has been selected."

  • 29 CFR 1910.217 (b) (7) (iii)

"A means of selecting Off, Inch, Single Stroke, and Continuous (when the continuous function is furnished) shall be supplied with the clutch/brake control to select type of operation of the press. Fixing of selection shall be by means capable of supervision by the employer."

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OSHA Sources of standards:

Sec. 1910.217 is derived from ANSI B 11.1 - 1971

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  • ANSI B 11.3 - 1982 (4.4.4.2.1)

"Emergency Stop Control. An emergency stop control shall be provided. This control shall immediatly stop the ram movement by momentary actuation of this control. The emergency stop control shall override every other control. Reactuation of the ram movement shall require the use of the predetermined operator's control station which has been selected."

  • NEMA ICS 2 - 1988 (2-216.22)

"Heavy-duty pushbuttons and selector switches shall have contact rating designations of A600, A300, A150, N600, N300, or N150 as shown in Table 2-125-1 for alternating current and Table 2-125-2 for direct current."

  • NEMA ICS 2 - 1988 (2-216.62)

"The color of those pushbuttons which perform a stop function shall be red."

  • CEN (European Committee for Standardization) EN 418 : 1992 (4.1.2)

"The control device and its actuator shall apply the principal of positive mechanical action."

  • CEN (European Committee for Standardization) EN 418 : 1992 (4.4.3)

"The emergency stop actuators shall be coloured red. As far as the background exists behind the actuator and as far as it is practicable, it shall be coloured yellow."
SINGLE PLUNGER
PUSHBUTTON SWITCHES

 

REES switches exceed the following:

Listed by Underwriters Laboratories per Standard UL 508 File No. E 58589

Certified by Canadian Standards Association per Standard C 22.2 File No. LR 3648

NEMA ICS 2-1988

CEI / I E C 947-5-1: 1990

CEN - EN 418:1992

Following are definitations of terms as relating to Pushbutton Switches:

Pushbutton - A pushbutton switch (pushbutton) is a switch having a manually operable plunger, rocker or button for actuating the switch.

Positive Break - The achievement of contact seperation as the direct result of a specified movement of the switch actuator through non-resilient members. (e.g. NOT dependant upon springs.

Positive Transfer - A contact system so designed that, it remains in one state (NO or NC) until the switch actuator moves to a "point of no return" then the contacts transfer and cannot be teased.

Slow-Make / Slow-Break - A contact system that opens and/or closes at the same rate (speed and time) that the actuator is moved.

Snap Action - A rapid motion of the contacts from one state to another, that is independant of the rate of travel of the actuator. Similar to "Positive Transfer".

Emergency Stop - A device that can be actuated in an emergency situation (one that arises from a sudden and unexpected need) and utilizes a positive mechanical action to function as a "stop category 0" device [i.e. stopping by immediate removal of power to the machine or mechanical disconnection between the hazardous elements and their machine actuator(s)].

Latching Contacts - After the cable tension has been removed the mechanical trip mechanism will return to its normal state; the contacts then require resetting through an independant means.

Operating Force - The amount of pushing or pulling force (in pounds) necessary to change the state of the switch from an at rest condition to one of contact change, that is, to make a set of Normally Open contacts or break a set of Normally Closed contacts.