The Saint Paul globe. (St. Paul, Minn.) 1896-1905, 1901-08-30


G. Must be insulated en- floors or base
frames which must be kept flied to pre-
vent absorption of moisture, and also
kent clean and dry. Where frame insu-
lation is impracticable. tie frame must
be permanently and effectively grounded.
A high potential machine, which. on
account of great weight or for other
reasons cannot have its frame insulated
from the ground should be surrounded
with an insulated platform, and so ar
ranged that a man must stand upon 1t
in order to touch any part of the ma
chine.
In case of a machine having an insu-
lated frame. if there is trouble from
static electricity due to belt friction, it
should be overcome by placing near
belt a metallic comb connected with the
earth, or by grounding the frame through
a very high resistance of not less than
two hundred ohms per volt generated by
the machine.
d. Every constant potential generator
must be protected from excessive cur
rent by a safety fuse, or equivalent de-
vice Of approved design. in each lead
wire. These devices should be placed on
the machine, or as near it as possible.
e. Must each be provided with a wa
ter-prCof cover.
f. Must each be provided with a name
plate, giving the makers name. the ca
pacity in volts and amperes. and the nor
NAL speed in revolution per minute.
2. Conductors
From generators to switchboards. rhe-
ostats or other instruments and thence
to outside lines
a Must be in plain sight or readily &C
cessible
b. Must have an approved insulating
covering. as required for similar work,
except that in Central Stations, on ex-
posed circuits, the wire which is used
must have a heavy braided non-combus-
tible outer covering.
c. Must be kept so rigidly in place
d. Must in all other respects be in
stalled under the same p1 ecautions as
required by rules for wires carrying a
current of the same volume and poten-
tial
3. Switchboard
a. Must be go placed as to reduce to
minimum the danger of communicating
fire to adjacent combuStible material.
b. Must be of non-combustible ma
terial or of hard wood in skeleton form,
filled TO prevent absorption of moisture.
c. Must be accessible from all sides
when the connections are on the back,
but may be placed against a brick or
stone wall when the wiring Is entirely
on the face.
d. Must be kept free from moisture.
e. Bus bars must be equipped in ac-
cordance with rules for placing con-
duCtOrS.
4. Resistance Boxes and Equal
1EerS-
a. Must be placed on switchboard or,
If not thereon, then at distance of
foot from combustible material, or sepa-
rated therefrom by a non-inf1ammable,
. non-absorptive insulating material.
3. Lightning Arresters-
a. Must be attached to each side of
every overhead circuit connected with
the station.
b. Must be located in readily accessible
places away from conibustible material,
and as near as practicable to the point
where the wires enter the building.
Station arresters should be placed in
plain sight on the switchboard
In all cases kinks, coils and sharp
bends in the wires, between the arresters
and the outdoor lines, must be avoided.
c. Must be connected with thorough
ly good and permanent ground connec-
ton by metallic strips of wire having
cOnductiVity not less than that of a No.
6 B. and S. copper wire, which must be
run as nearly in a straight line as pos
sible from the arresters to the earth
connection.
@. Care and Attendance
a. A competent man must be kept on
duty where the generators are operating.
b. Oily waste must be kept in approved
metal cans, and removed daily. APPROX
ed waste cans shah have self-closing
covers, and be made of metal the same
shall have legs raising the can three
inches from the floor.
z. Testing of Insulation Resist
aRce-
a. All circuits must be provided with
reliable ground detectOrs.
Detectors which Indicate continuously,
and give an instant and permanent, or
other, indication of a ground, are prefer
able. Ground wires from detectors must
not be attached to gas pipes or structural
iron work within the building
b. Where continuously Indicating de-
tectOrs are not feasible, the circuit
should be tested at least once per day.
c. Data obtained from all tests must
be preserved for examination by the In
spector. All generators, motors. wires,
lamps and other electrical appliances
shall at all times test free from
grounds.
When the ground detector at the gem
orator shows a ground on the wiring. the
owner of such generator or wires in the
case of an insulated plant. shall immedi-
ately cause such ground to be located
and raised. or to cut the current eff
from such wires. If the generators are
Central Station generators, then the com.
pany or person owning or operating them
shall Immediately locate such ground
and notify the Inspector, who shall inn
mediately order the owner or agents of
the owners Of the wires, or of the build
ing where such ground wires are located,
to raise such ground, and said owners or
agents shall cause such ground to be
raised, or the current cut off from all
grounded wires in said building within
forty-eieht hours after notice has been
served on them by the Inspector. And
such grounded wires shall not thereafter
be used for conveying current for cleo
trio light or other purposes until they
test clear of grounds.
These rules on testing to be applied at
such places as may be designated by the
Inspector
8. Motors
a Must be insulated on floors or base
frames, which must be kept filed to pre-
vent absorption of moisture; and must be
kept clean and dry Where frame insu-
lation is inpracticable, the frame must
be permanently and effectively grounded
4 high potential machine which, on ac-
count of great weight, or for other rea-
sons, cannot have its frame insulated,
should be surrounded with an insulated
platform, and so arranged that man
must stand upon it in order to touch any
part Of the machine.
In case of machine having an insu-
lated frame. If there is trouble from
static electricity due to belt friction, it
should be overcome by placing near the
belt metallic comb connected to the
earth, or by grounding the frame
through a very high resistance of not
less than two hundred ohmS per volt
generated by the machine
b. Must be wired under the same pre-
cautions as required by rules for wires
carrying a current of the same volume
and potential
The LEADS or branch currents should be