 |
|||
|
|
|||
| ||||||||||
|
|  MIL-T-15108C(NAVY)
Table II - Transformer characteristics (con.).
Transformer to be submitted from each division for qualification (see 4.3.1) .
Mounting feet and braces included in the "E" and "F" dimensions specified on figures 1
and 2.
Regulation impedance and total losses are to be based on a reference copper temperature
of 75C.
Values for inrush current are applicable to transformers with 450-volt primary. The
maximum peak inrush current for transformers with other primary voltage ratings shall
be the same percentage of the primary load current.
3.12 Ratio. Transformers' turn ratio shall not vary more than plus or minus 1.0
percent from ratio of rated voltages indicated on the identification plates.
3.13 Polarity.
Transformers shall be of additive polarity.
#
3.14 Shockproofness. Transformers shall be designed to withstand high-impact shock
without mechanical damage or failure of parts as specified in MIL-S-901 for grade A, class I,
type A (see 4.6.10).
#
Transformers shall be designed to withstand the short circuit test
3.15 Short circuit.
specified in 4.6.13.
#
3.16 Weight. Transformers complete with case and including wiring and mounting pro-
vision shall not exceed the weights shown in table II.
#
3.17 Volume. Transformers' volume shall not exceed the volume in cubic inches shown
in table II. Maximum dimension in each direction shall be used in determining the volume.
#
3.18 Dielectric strength. Transformers shall be designed and constructed so that
the insulation system for each separate winding will withstand a root means square (rms)
dielectric test voltage of 4000 alternating current (a.c.) volts, sinusoidal waveform,
60 Hz, applied for 1 minute between the winding and all other windings connected together
and grounded to the core(s) and frame.
#
3.19 Mounting. Mounting dimensions of transformers shall be as specified on figures
1 and 2. Holes provided for mounting and bracing shall not be slotted. Transformers with
kVA rating 1 through 25 kVA shall be bulkhead mounted. Transformers with kVA rating 37.5
kVA and larger shall be deck mounted. Transformers, when in place onboard ship, are mounted
in banks with a minimum distance of 2 inches between units. Under this condition, the
temperature rises (see 3.10) shall not be exceeded. Braces will be provided by the ship-
builder.
#
3.20 Winding resistance. Measured values (see 4.6.1) of winding resistance corrected
for temperature difference shall be compared to the design value of applicable winding
resistance given on the transformer drawing, and deviations therefrom shall be computed in
percent of design value. The algebraic average of all such deviations (for windings) of
transformers on each contract or order shall fall within the limits of minus 5 to plus 0 per-
cent, inclusive. Each winding individually shall fall within the range limits of minus 10
plus 5 percent, inclusive.
4
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals