 |
|||
|
|
|||
| ||||||||||
|
|  MIL-I-19028E(OS)
4.4.3.7.4 Imput impedance:
1 megohm shunted by 50 micromicrofarads
minimum.
4.4.3.8 High potential test set: The high potential test set shall
be capable of furnishing 500 volts rms and 1250 volts rms at 60 Hz. The
test set will be used for insulation testing and shall include an alarm
bell or light, or a combination of both, to indicate when any arcing or
breakdown of insulation occurs.
4.4.3.9 Dummy load: Three each of the loads described are required
to make up the three phase delta inverter load. One resistive leg and
one reactive-resistive leg are to be connected in parallel for each phase
load. See Figure 4.
4.4.3.9.1 Resistive leg: A resistor or combination of resistors suf-
ficient to provide 298 plus or minus 5 ohms total, with a tap point at 188
plus or minus 2.5 ohms. Maximum leg current: 0.65 ampere rms.
4.4.3.9.2 Reactive-resistive leg: The reactive-resistive leg shall
consist of inductance and resistance in series. The resistive element may
or may not be entirely made up of the inherent resistance of the inductor
coil. Total inductance of 54.5 plus or minus 1 millihenries, with a tap
point at 34.5 plus or minus 0.5 millihenries. Total resistance 45 plus
or minus 1 ohms, with a tap point at 28.5 plus or minus 0.5 ohms. The re-
active-resistive leg shall be constructed so that the two tap points may
be used simultaneously. Maximum leg current: 1.32 amperes rms at 400 Hz.
4.4.3.10 Current shunt: A four terminal resistor (two current terminals
and two voltage terminals) of 0.003 to 0,01 ohm having an accuracy of 1
percent and capable of carrying 50 amps continuous.
4.4.3.11 Interference measuring device: Stoddard, Model N17-10A or
equivalent.
4.4.3.12 Amplitude of vibration measuring equipment: capable of measur-
ing 0.0005 inch peak-to-peak or less.
4.4.3.13 Resilient ribbed neoprene pad: 5/16 inch thick, Isomode Pad,
manufactured by MB Electronics, or equal.
4.4.4 Adjustment. Initial adjustment of output voltage and frequency
shall be made as specified below. No additional adjustments of output
voltage and frequency shall be made unless specifically permitted by the
applicable test paragraphs (See 3.3.1.3.2 and 3.3.1.3.3).
4.4.4.1 Connect the tapped parts of the 3-phase delta dummy load of
4.4.3.9 to the inverter output terminals.
15
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals