Volltext: Optic Projection: Principles, Installation and Use of the Magic Lantern, Projection Microscope, Reflecting Lantern, Moving Picture Machine

Ch. XIII) 
one cannot make a wrong connection (fig. 268A). Such an attach¬ 
ment would also serve for alternating current, but is unnecessary, 
as it makes no difference which way the attachment is connected. 
The conductor from the electric supply in the outlet box to the 
lamp switch, if the distance is small, not over 2 to 3 meters (6 to 10 
ft.), is most conveniently made of flexible cable of the proper 
carrying capacity (see the table of carrying capacity of flexible 
Fiu. 268. Separable Wall Receptacles, Polarized (/l) and 
Non-Polarized (B). 
(Cuts loaned by H. Hubbell, Inc ). 
With direct current, a polarized attachment insures the same polarity with¬ 
out attention on the part of the operator; with the non-polarizcd form there 
is liability of reversing the polarity unless the connections are specially marked, 
and care is taken in putting the separable cap in position. Either form can be 
used with alternating current also. 
electric cables). The two wires or cables are often enclosed in a 
common sheath. 
§ 698. In connecting the two wires to the attachment cap, the 
insulation is removed for a short distance (1 to 2 cm. Y* in.), the 
wires scraped clean, twisted all together, and then turned to a loop 
to surround the set screw. Great care must be taken to avoid 
leaving any of the strands free; this would lessen the carrying 
capacity, but more important still, they might become displaced 
and make a short circuit (§688).


Sehr geehrte Benutzerin, sehr geehrter Benutzer,

aufgrund der aktuellen Entwicklungen in der Webtechnologie, die im Goobi viewer verwendet wird, unterstützt die Software den von Ihnen verwendeten Browser nicht mehr.

Bitte benutzen Sie einen der folgenden Browser, um diese Seite korrekt darstellen zu können.

Vielen Dank für Ihr Verständnis.