PS Engineering PMA4000 Installation Manual - Manual (Page 11)

PS Engineering
PMA4000 Series Audio Selector Panel and Intercom System
Installation Manual
200-041-0002 Page 2-5 Rev 5, March 2007
To use this function, a normally open (NO) momentary switch is installed between the
bottom connector P1, pin 11 and aircraft ground. A low-current switch is recommended.
A radio signal of more than 1 VRMS is needed to trigger the IRS. Therefore, if the IRS
does not seem to be recording, increase the aircraft radio volume slightly.
2.5 Adjustments
The PMA4000 is factory adjusted to accommodate the typical requirements for most
aircraft configurations. There is an adjustment for the cabin speaker volume, ac-
cessed through the left side (viewed from the front) of the unit. To make the neces-
sary adjustments, use a small jeweler's slotted screwdriver. Turning the adjustment
counter clockwise will increase the volume.
2.6 Panel Installation
1. Insert the PMA4000 from behind the instrument panel.
2. Use caution when aligning the holes for the knobs, toggle switches and push-buttons.
3. If necessary, add the shim spacers between the unit and the back side of the instru-
ment panel, so the selector buttons are the correct depth for the shoulder of the switch
to mate with the front plate.
Note: The total panel thickness should be about 0.100” Add the necessary shims to
come as close to 0.100” as possible. For instance, a .050” instrument panel, add a
.050” shim.
4. Carefully place the aluminum face-plate over the knob shafts and push-buttons, seat-
ing the push-button shoulders in the panel.
5. Secure the unit, using the two # 6-32 round head screws provided.
6. Install the knobs over the volume control shaft.
2.6.1.1 Instrument hole mounting
The PMA4000 can be mounted in a 2 ¼-inch instrument hole, using the adapter plate,
part number 575-004-0001 (not supplied).
1. Insert a .090” shim (430-400-0090, not supplied) between the PMA4000 and the
mounting plate. Use caution to align the selector buttons in the openings.
2. Secure the mounting plate to the unit and shim assembly with the two # 6-32 round
head screws provided. Use caution to align the selector buttons in the openings
3. Mount the intercom and plate to the instrument panel from behind, using aircraft in-
strument hardware, not supplied.
4. Install the knobs over the volume control shafts.
2.7 Post Installation Checkout
After wiring is complete, verify aircraft power is ONLY on pin 13 of the bottom connec-
tor, and airframe ground on bottom connector pin 25. Failure to do so will cause serious
internal damage and void PS Engineering's warranty.
To avoid stray voltages, the other avionics should be turned off.