Garmin G3X Installation Manual page 738

Voltage
The GEA 24 and GSU 73 have provisions to monitor bus voltage from two different sources. Bus voltage
can be connected to the physical input pins, measured internally by the LRU, or communicated from
another data source.
Voltage Inputs: The VOLTS 1 and VOLTS 2 input pins on the GEA 24 and GSU 73 can be configured to
monitor a directly connected bus voltage. VOLTS 1 can be configured either as "Bus 1" or "Main Bus",
and VOLTS 2 can be configured either as "Bus 2" or "Aux Bus". The only difference is the text labels
used to display the voltage gauges in the EIS display and Engine Page.
EIS Power Input: Instead of monitoring a voltage on a physical input pin, the GEA 24 and GSU 73 can
monitor the voltage applied to their AIRCRAFT POWER pins. Configure the VOLTS 1 input to "EIS
Power Input 1 Volts" to monitor AIRCRAFT POWER 1, and configure the VOLTS 2 input to "EIS Power
Input 2 Volts" to monitor AIRCRAFT POWER 2.
Vertical Power: When using a Vertical Power unit, configure VOLTS 1 to "Vertical Power Main Batt
Volts" or "Vertical Power Bus 1 Volts" to use primary battery/bus voltage data from the Vertical Power
unit. Configure VOLTS 2 to "Vertical Power Aux Batt Volts" or "Vertical Power Bus 2 Volts" to use
secondary battery/bus voltage data from the Vertical Power unit.
Rotax 912iS: For the GEA 24, configure the VOLTS 1 input to "Rotax FADEC ECU Bus A Volts" to use
power supply voltage data from Lane A of the Rotax 912iS ECU. Configure the VOLTS 2 input to "Rotax
FADEC ECU Bus B Volts" to power supply voltage data from ECU Lane B.
Current
The GEA 24 and GSU 73 have provisions to monitor bus current from two different sources. Current can
be measured either using a shunt resistor such as the UMA 1C4 (50mV/100A type) or a Hall effect sensor
such as the Amploc KEY100 series.
Shunt Sensors: Shunt sensors are connected to the SHUNT 1 and SHUNT 2 inputs on the GEA 24 and
GSU 73 (see Figure 27-2.2
"Bus 1 Amps" or "Main Bus Amps". The SHUNT 2 input can be configured to display either "Bus 2
Amps" or "Essential Bus Amps".
Hall Effect Sensors: Hall effect current sensors are connected to the GEA 24 or GSU 73 general purpose
(GP) inputs (see Figure 27-2.2
adjust for installation differences (see
current sensors on GP inputs are similar to those supported for shunt current sensors:
• Bus 1 Amps (Hall)
• Bus 2 Amps (Hall)
• Main Bus Amps (Hall)
• Essential Bus Amps (Hall)
Vertical Power: When using a Vertical Power unit, configure SHUNT 1 to "Vertical Power Main Bus
Amps" or "Vertical Power Bus 1 Amps" to use primary bus current data from the Vertical Power unit.
Configure Shunt 2 to "Vertical Power Bus 2 Amps" to use secondary bus current data from the Vertical
Power unit.
190-01115-01 G3X/G3X Touch Install Manual - GDU 45X/46X Config and Post Install Checkout
Rev. AA
and Figure 27-3.1). The SHUNT 1 input can be configured to display either
and Figure 27-3.1). Hall effect sensors can optionally be calibrated to
Section 32.4.25.3). The supported configurations for Hall effect
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