# SYSTEMS/ELEC

![](https://cdn.document360.io/417c2d4d-fdb8-4d4d-b11d-011fe445d776/Images/Documentation/systemselec-page-image-7v60zmek.png)

### IDG (INTEGRATED DRIVE GENERATOR) <a href="#idg-integrated-drive-generator" id="idg-integrated-drive-generator"></a>

* Icon and its outputs (voltage/frequency/amperage) are always displayed.

### AC EXTERNAL POWER (AC GPU) <a href="#ac-external-power-ac-gpu" id="ac-external-power-ac-gpu"></a>

* AC GPU icon and its outputs (voltage/amperage/frequency) are displayed only when the AC GPU is connected and available.

### APU <a href="#apu" id="apu"></a>

* APU icon and its outputs (voltage/amperage/frequency) are not displayed until the APU is available (3 seconds after 95% rpm).
* Green – APU available and APU GEN pushed in, White – APU available and APU GEN pushed out.

### ELECTRICAL BUSES <a href="#electrical-buses" id="electrical-buses"></a>

* Always displayed.

### TRU (TRANSFORMER RECTIFIER UNIT) <a href="#tru-transformer-rectifier-unit" id="tru-transformer-rectifier-unit"></a>

* Icon and its outputs (voltage/amperage) are always displayed.
* Green – TRU available and toggle switch is AUTO, White – TRU available and toggle switch is OFF.

![](https://cdn.document360.io/417c2d4d-fdb8-4d4d-b11d-011fe445d776/Images/Documentation/systemselec-page-image-rqml6an2.png)

### Batteries <a href="#batteries" id="batteries"></a>

* Icon and their outputs (voltage/temperature) are always displayed.

### DC EXTERNAL POWER (DC GPU) <a href="#dc-external-power-dc-gpu" id="dc-external-power-dc-gpu"></a>

* Displayed only when the DC GPU is connected and available.
* Cyan IN USE indication is displayed, centered above the DC GPU icon, whenever the DC GPU is connected and supplying power to the aircraft electrical system.

### ELECTRICAL FLOW LINE <a href="#electrical-flow-line" id="electrical-flow-line"></a>

* Flow line icons illustrate voltage sensing.
* Green – voltage is sensed, White – voltage is not sensed.

### RAT (RAM AIR TURBINE) <a href="#rat-ram-air-turbine" id="rat-ram-air-turbine"></a>

* Only displayed when the RAT is deployed.