(a) General. Disconnecting switches shall be
permitted to be single-pole or multiple-pole.
(b) Isolating Means. A suitable air break
switching device shall be installed to isolate each oil switch or group of oil
switches from all sources of supply unless automatic disconnecting switchgear
equipment of the metal-clad draw-out type is used.
EXCEPTION: In highly corrosive or flammable
atmospheres, suitable isolating means other than air break shall be used, or
the isolating means shall be installed in an enclosure approved for use in such
locations of the particular hazard involved.
(c) Accessible to Qualified Persons Only.
Disconnecting switches installed in locations where only qualified persons are
permitted access shall be installed in suitable enclosures, or shall be
elevated above the floor not less than clearances shown in Section
2934.
(d) Accessible to Other Than Qualified
Persons. Disconnecting switches installed in any location where other than
qualified persons have access shall be installed in suitable enclosures.
The door or cover of the enclosure shall be kept
closed, except when opened for operation or inspection. If installed so that
the bottom of the enclosure is less than 8 feet above the floor, the door or
cover shall be kept locked.
When disconnecting switches are operable from outside
the enclosure by a remote control mechanism, the operating handle or lever
shall be kept locked when in either the open or closed
position.
(e) Operation.
Isolating switches shall be provided with suitable means for safe normal
operation. This operating means shall be permitted to be an insulated
hookstick, an insulated external operating handle, or remote control mechanism.
Disconnecting switches shall provide a visible gap in the circuit adequate for
the operating voltage.
Provision shall be made to observe the position of the
blades of disconnecting switches. If viewing windows are provided, they shall
be shatterproof, of adequate size, and suitably located to permit viewing of
all contacts. Metal-enclosed switches other than those designed for hookstick
operation shall be arranged to be locked in the open position. Multiple
switches in the same enclosure shall be equipped with a connection
diagram.
(f) Rating.
Disconnecting switches shall have current and voltage ratings not less than the
full-load current and operating voltage of the circuit. The momentary rating of
disconnecting switches shall equal or exceed the asymmetrical short circuit
current available at the switch location. The asymmetrical short circuit
current shall include contributions from all connected sources of energy, such
as other lines, generators, large motors, etc.
(g) Identification. The disconnecting
switches shall have a permanent and legible nameplate including the following
information: continuous current rating, maximum voltage rating, momentary
current rating.
(h) Warning Signs.
Unless so interlocked that they cannot be opened under load, disconnecting
switches shall be provided with permanent warning signs having letters at least
2 inches high and reading as follows: "Warning--Disconnecting Switch--Do Not
Open Under Load." When a group of disconnecting switches is installed in one
room or enclosure, a single sign may be sufficient.
(i) Barriers. Suitable barriers shall be
installed on both sides of each pole of disconnecting switches mounted indoors.
(Title 24, Part 3, Section
3-710 -
22.)
Notes
Cal. Code Regs. Tit. 8, §
2835
1.
Amendment of subsection (b) filed 2-9-78; effective thirtieth day thereafter
(Register 78, No. 6).
2. Editorial correction filed 11-2-83
(Register 83, No. 45).
3. Amendment of subsections (a) and (e) filed
12-10-87; operative 1-9-88 (Register 88, No. 1).
Note: Authority cited: Section
142.3, Labor
Code. Reference: Section
142.3, Labor
Code; and Section
18943(c),
Health and Safety Code.
1. Amendment of
subsection (b) filed 2-9-78; effective thirtieth day thereafter (Register 78,
No. 6).
2. Editorial correction filed 11-2-83 (Register 83, No.
45).
3. Amendment of subsections (a) and (e) filed 12-10-87;
operative 1-9-88 (Register 88, No. 1).