UL 1047-2015 pdf download

UL 1047-2015 pdf download.Isolated Power Systems Equipment.

29.2 For the test, the equipment s to be mounted or supported as in service and operated under conditions approximating those of normal operation.
29.3 Permanently-connected isolated power systems equipment is to be supported on the surface of a wood wall not less than 3/8 in (9.5 mm) thick, coated with flat black paint. Two or more such walls having such width and height that they extend not less than 2 It (0.6 m) beyond the physical limits of the equipment are to be fastened together to form a 90•degree angle. The equipment is to be located as close to the inside corner of the wall as its construction will permit.
29.4 Surface-mounted equipment is to be mounted directly on the surface of the wall in the manner described in 29.3.
29.5 Flush-mounted equipment is to be mounted in a box-like structure of 3/8-in (9.5-mm) thick wood or the equivalent, coated with flat black paint on the inside surface, the walls of the box are to be perpendicular to its back. The internal dimensions of the box-like structure are to be such that the walls make a dose fit with the equipment enclosure on the tour sides and the rear, and has a flat front surface simulating the wall surface in which the equipment is designed to be mounted. The assembly of the equipment and wood box is to be mounted in an appropriate opening in the wall described in 29.3.
29.6 The isolating transformer is to be connected to a source of rated primary voltage and the secondary connected to a resistive load adjusted to draw rated secondary current. As an alternate to the resistive-load method, the load-back method described in 29.7 may be employed. See also 29.8.
Exception; The isolating transformer of an isolated power center intended for x-ray equipment only shall be connected to a source of rated pnmary voltage and the secondary connected to a resistance load adjusted to draw 80 percent of the rating of the overcurrent-protective device associated with the secondary circuit.
29.7 In the load-back method the primary and secondary windings of the transformer under test are to be connected In parallel to the primary and secondary windings, respectively, of a similar auxiliary transfomier. The primary windings are to be connected to a source of rated primary voltage for the test transformer and rated full-load secondary current is to be circulated in the secondaries by impressing a voltage across a break in the secondary circuit. The impressed voltage, which may be introduced by a loading transformer, is to be just sufficient to circulate full-load rated secondary current.
29.8 The distribution section (with transformer operating in the load-back method) shall be loaded as indicated in 29.9 and 29.10 so that rated currents will be caused to flow in the main bus bars, Any convenient voltage supply may be used as long as rated current flows through the unit. This test may also be combined with 29.6 it the resistive-load method Is used.
29.9 If the branch circuits are protected by fuses, dummy fuses or the equivalent shall be used in place of regular fuses in the fuseholders. All branch circuits used shall be loaded to 100 percent of the rating of the branch circuits, except that one branch circuit may be loaded to a lesser value as necessary to achieve the required test current in the main bus bars.
29.10 If the branch circuits are protected by circuit breakers, each branch circuit used shall be loaded to 80 percent of the rating of the branch circuits, except that one branch circuit may be loaded to a lesser value as necessary to achieve the required test current in the main bus bars.