Rev 4/14/21
GD-40 Installation/Operation Manual
The GD-40 is not approved for installation in certified aircraft.
Installation:
Mechanical
Mount the GD-40 in a non-dusty area in the cockpit. Mount such that there is a no obstruction to the fan. Possible locations include bulkheads
behind the instrument panel and side panels.
Mount the supplied Bi-Color LED and button next to each other in a visible location on the instrument panel.
Electrical
Configuring your Installation:
The GD-40 is capable of producing warnings via LED illumination, Audio warning, EFIS communications and a
discrete relay switch. Any combination of these external connections may be made as desired for your installation. At a minimum the LED and button
should be installed.
V+
(power) 12-28 Volts DC, Connect to the avionics bus via a 1 Amp fuse.
GND
(Ground) Two identical grounds are provided. One should be connected to the aircraft ground. The other may be used for the LED connection,
audio shield, button ground and/or Serial data cable shield. It is acceptable to connect more than one wire to a ground terminal.
WARNING!! Do NOT connect the LED to 12V. Damage will occur.
LED1
(Red LED)
Connect to the red wire on the supplied LED
LED2
(Green LED)
Connect to green wire on the supplied LED
(connect LED the black wire to ground
GND
)
RX
(Serial Receive) Connect to EFIS serial port “Transmit”.
TX
(Serial Transmit) Connect to EFIS serial port “Receive”.
(Use a two conductor shielded wire for the data connection. Connect one end of the shield to ground)
AUD
(audio out) Connect to an unswitched audio input in on your radio or intercom. Use 22-24AWG shielded wire. Connect one end of the shield to
ground. If your radio or audio panel does not have an unswitched audio input you will need to purchase an audio mixer. We suggest our AP-60 Mixer.
BUT
(button) Connect to one terminal of the supplied button. Connect the other button terminal to ground. We suggest using 22-24AWG shielded
wire using the shield as the ground connection.
RLY
(Relay) This terminal connects to ground (is pulled low) when a CO alarm is present. Connect this to an EFIS “switch input” or it can complete
the circuit for an external warning lamp. Do not connect this terminal to 12-28 Volts
Setup:
Once you have connected the detector, perform the following tests to verify your installation.
Test 1
: PRESS and HOLD the button, RELEASE the button when the LED begins to flash RED and GREEN.
Confirm the following occurs:
•
The Red LED should flash for 20 seconds
•
“Danger Carbon Monoxide” will be played over the audio system
•
A connected EFIS should report a CO warning and a level of 500PPM for 20 seconds.
•
The “RLY” connection will be connected to ground (pulled low)
Test 2
: PRESS and RELEASE the button to perform the following tests:
•
The green LED should flash several times
•
If Test 1 is in progress, the EFIS warning will be cancelled and the RLY switch connection will be opened
Volume Control:
An audio volume control is located next to the terminal strip. Be careful not to force the potentiometer past its limits, it is delicate.
Configuring your EFIS:
Configure the EFIS Serial port connected to the GD-40 for CO detector data.
