ATR 42 Model : 400/500
AC CONSTANT FREQUENCY
ELECTRICAL SYSTEM
P 1
NOV 99
001
1.06
.
30
30.1 DESCRIPTION
GENERATION
The source of constant frequency (400 Hz) AC power consists of two static inverters
(INV).
The inverters are rack mounted and cooled by forced air with provisions for natural
convection cooling.
The static inverter design characteristics are as follows :
- Power
500 VA
- Output voltage
115 V
"
4V and 26 V
"
1V
- Frequency
400 Hz
"
5 Hz
- Type
single phase
The two inverters are powered respectively from DC BUS 1 and DC BUS 2. The input
voltage range is between 18 VDC and 31 VDC for satisfactory operation.
In event of one DC BUS loss, corresponding inverter is not supplied, but corresponding
AC BUS is supplied by AC BTR (BTC pb).
In event of both DC BUS power loss, INV1 is automatically supplied by HOT MAIN BAT
BUS, or by HOT EMER BAT BUS in OVRD configuration or by TRU when selected ON.
The maximum power available on each 26 VAC BUS is 250VA.
R
Note : Two AC electrical networks are supplied by the inverters :
115 VAC and 26 VAC. Only one is shown on the schematics.
AA
AviationLearning.net
01/07//2018 REV 1 These notes are not revised after issue For Training Purposes Only
Page 251 of 764