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TRU-28 28V Transformer Rectifier Unit

delivery time

upon request

The TRU–28 transformer rectifier unit will start and power all known 28V DC aircraft. Environmentally clean and easy to use, the unit offers users significant operating benefits. Designed in collaboration with Powervamp and built to the highest industry standards (MILSTD 704, ISO 6858), it produces the highest quality output signal with minimal AC ripple and is guaranteed to be accepted by all DC aircraft. The 12 pulse rectification technology used ensures a low input total harmonic distortion at nominal loads, adding to the efficiency of the system. The TRU–28 produces a regulated 28V DC output and can deliver a constant current of 600A with engine starting peaks of up to 2400A. The current limiting feature enables the user to limit the output current to the aircraft and can be accessed and set via the digital display. The user can access the line drop compensation feature via the display menu to increase/decrease the output voltage at the plug within the limits of ISO 6858. The TRU–28 is a compact solid state module built to IP55 protection, designed for internal/external fixed or mobile use. With its weather-resistant, stainless steel case with large caster wheels, the unit can be easily moved by hand over uneven surfaces. Power consumption is reduced by the unique ‘wake/sleep’ feature which powers down the TRU–28 after sensing that there has been no current draw for a pre-set time.

Input


Voltage: 208-230-240-380-440-460- 480V AC three-phase (field adjustable)

Frequency: 50/60Hz

Rectification: 12 pulse

Power factor: > 0.80 @ nominal load

Line current: 26A – 62A @ nominal load (voltage dependent)



Output


Voltage: 28 V DC

Curren:t 600 amps continuous

Engine start capacity: 2400 A selectable

Ripple: Less than 1% at full load

Line drop compensation: Up to 15%



Overload Ratings


2400 A: 2 seconds

2100 A: 10 seconds

1800 A: 30 seconds

1200 A: 40 seconds



Efficiency


Overall efficiency: Typically > 0.92 % @ nominal load

Stand by losses: 250 W (Electronics)

No load losses: 500 W (Output on)



Environmental


Acoustic noise: 59 dB (A) @ 1 m

Temperature range: -40°C to +50°C (-40°F to +122°F)

Water ingress: IP55



Protections


Over/under voltage at the output

Over/under voltage at the Input

Reverse current at the output

Reverse polarity at the output

Phase sequence at the input

Over temperature

Internal PSU voltage monitoring

Short circuit at the output

Over/under voltage trip in the case that

U<20 VDC for more than 4 seconds

U>32 VDC for more than 4 seconds

U<40 VDC for more than 1 second



Standards


ISO 6858: Aircraft ground support electrical supplies

MIL-704E: Aircraft electric power characteristics

BS 2G 219: General requirements for ground support equipment

EN 62040-1-1 LVD: Safety standards

EN 61558-2-6 LVD: Safety standards

EN 61000-6-2 EMC: Immunity standard

EN 61000-6-4 EMC: Emission standards

BS 2G 219: General requirements for ground support equipment

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