Saab 340 Electrical

Front 1

Where are the batteries located

Back 1

Aft of the wing

Front 2

How are the batteries are ventilated

Back 2

fan on the ground Ram air in flight

Front 3

Voltage of starter generators

Back 3

28V

Front 4

Starter up to generator when

Back 4

Starter up to 55% Ng generators at 60% Ng

Front 5

How the generators controlled

Back 5

GCU

Front 6

GPU limit

Back 6

30 V Max between 1200 to 1600 Amps

Front 7

What runs the starter generators

Back 7

NG gearbox

Front 8

What are the two wild frequency generators

Back 8

AC 115 V

Driven by prop gearbox

Use only for ice protection

Front 9

What are the two engine driven alternators

Back 9

Driven by the accessory gearbox

Powers DECU, NG gauge, igniters

Front 10

Emergency power for lights

Back 10

5 NiCad batteries located under the floor

Front 11

PDU

Back 11

2 Power distribution unit

Brain of the select System

Power and logic for all relays

Front 12

GCU

Back 12

2 Generator control unit

Fault protection

Field excitation

Voltage regulation 27.5 to 29 V

Controls start cycle

Self test

Front 13

Hot battery bus item Left

DEBATE

Back 13

Dome Light

Engine Extinguisher (L)

Batt Voltage (L)

A HARS 1 Backup

T Handle (L)

Extinguisher ( Cargo#1)

Front 14

Generator busses ON when

Back 14

Battery relays closed

Battery switch is on at least 18 V

Battery temperature is less than 71°

External power is in the off position

Front 15

Battery busses

Back 15

Powered as long as the respective Gen Bus is powered

Feeds main, essential & emergency buses

Supplies power to the bus to connect in auto mode

Charges the JETPAC through diode

Front 16

Essential busses

Back 16

Powered from the battery bus through essential bus Relay

Is Sched during Start

Front 17

The Essential bus is powered from the batt bus trough essential bus really

when essential bus relay closes ?

Back 17

18 V on the system

Respective bat bus on

No start in progress

Front 18

Busses Schematics

Back 18

Back (Definition)

Front 19

Batteries

Back 19

2 24V Nicads 43 Amps/h

Front 20

Gen Ov Temp light

Back 20

> 150 Degrees Celsius

Front 21

Bat Hot Light

Back 21

71deg

Front 22

2 Bat Thermal switches

Back 22

One at 57°C“No Bat Start”

One at 71°C “ Bat Hot”

Front 23

Hot Batt Bus R

REBATE

Back 23

Refueling Panel

Engine Extinguisher (R)

Batt Voltage (R)

A HARS 2 Backup

T Handle (R)

Extinguisher Cargo # 2

Front 24

Where can you find what attached to the Electrical Busses

Back 24

Electrical Power Distribution List in AOM

Front 25

When is the Bus Tue Relaybtrips open

Back 25

When current of at the relay exceed 800 Amps

Front 26

3 things for The Gen Relay to Close

Back 26

Sw On

Self Test

Ng > 60%

Front 27

3 conditions for the Generator Relay to open

Back 27

External power really open

Engine Start completed

Generator field current reset