 |
|||
|
|
|||
| ||||||||||
|
|  MIL-T-26219A
3.10.3 Gear box. The gear box shall be enclosed within a rigidly
constructed h ousing equipped with two aircraft generator mounting pads. One
of the pads shall be located at the level of the control panel as shown on
Figure 2 to provide a drive outlet for testing tachometer generators.
The
second pad shall be located inside the case and shall have an AN5547-2
tachometer generator attached thereto. The gear box shall be designed for
continous duty at any speed over the range from O to 5000 revolutions per
minute when connected to the output load of the test set. The gearing shall
be adequately lubricated, The drives in the tachometer generator mounting
pads shall rotate simultaneously in the clockwise direction (when viewed from
the outer mounting end of the pads) and at the same speed. The mounting pads
shall conform to AND20005 insofar as mounting arrangement and basic drive
connection details are concerned. With respect to the pad mounted on the
panel, provisions shall be incorporated for permitting tachometer generators
to be quickly and easily attached and detached therefrom. An additional pad
may be mounted on the panel to facilitate testing of 4-pole generators.
The requirements outlined in the foregoing paragraph shall not be
NOTE:
construed as meaning that the master AN5547-2 four pole generator incorporated
within the test set will be driven at a speed in excess of 2500 rpm under load.
3.11 Rotational speed indicating system. The rotational speed indicating
system (digital speed indicator) shall represent a stable and precision remote
indicating system of the electronic type,
It shall be designed to accept
electrical output signals from either the master 4-pole generator contained
within the test set or from any external 2- or 4-pole standard tachometer
percent rpm, consistent with the setting of the selector switch. The speed
registered by the indicating system shall be directly related and based upon
the speed of the output drives incorporated within the tachometer mounting
pads.
Tachometer generators of the four pole type are designed to be driven
NOTE:
at one half engine speed and produce a three phase output voltage having a
frequency of two cycles, resulting in the associated tachometer indicator
registering full engine speed. Tachometer generators of the two pole type are
driven at full engine speed and produce a three phase output voltage having a
frequency of one cycle, resulting in the associated tachometer indicator
registering full engine speed. Tachometer generators of the four pole type
are normally furnished for reciprocating engine aircraft with the indicators
calibrated in revolutions per minute. Tachometer generators of the two pole
type are normally furnished on jet engine aircraft with the indicators
calibrated in percent rpm.
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals