The F900PST-3200 proximity switch tester is designed utilizing information from the proximity switch manufacturer's specifications and its purpose is to test proximity switches only. This unit is powered by 9V internal batteries (24V min. recommended) and/or external 24-28V power supply.

Note: Attempting to connect this unit to the aircraft system wiring may cause damage to aircraft electrical components.

Instructions:

1. Select appropriate 3 or 6 pin connector on Tester Box and connect directly to the Proximity Switch pigtail or connector in question.

-Do not attempt to connect proximity test box pigtails to the aircraft side of the proximity switch circuit-

2. Move three position selector to the appropriate position, 3 pin or 6 pin depending on pins to be checked (Reference aircraft wiring manual for 6 pin connectors).

3. Turn test box On-Off switch to "On". Actuate "Push-to Test" switch and check that green light illuminates. A change in the brightness of the green light indicates an improper ground on the proximity switch. This can be used to verify that the output signal from the proximity switch has a proper ground.

To actuate the proximity switch place a metallic washer flat against the surface to determine if the proximity switch state changes, such as open signal to ground signal, which will light the green light. If the proximity switch is a normally closed type, the switch should change from a green light to an unlit green light when the metallic object is held flat on the proximity switch sensing surface.

Reference items 1-10 below for information on test unit functions.

FALCON 50 900/2000
PROXIMITY SWITCH TEST BOX

<see photo>

1. GREEN LIGHT lights up when proximity switch under test has a ground on its signal output wire.

2. THREE POSITION PROXIMITY SWITCH SELECTOR.

• This switch ties one proximity switch at a time to the green light.
  
  • Position 1
    Ties the proximity switch that is connected to the small three-pin connector to the green light.
  • Position 2
    Ties the proximity switch (Pins ABC) of the larger six-pin connector to the green light.
  • Position 3
    Ties the proximity switch (Pins FED) of the six-pin connector to the green light.

3. PRESS-TO-TEST SWITCH. Lights the green light when pressed down. A change in the brightness of the green light indicates an improper ground on the proximity switch. This can be used to verify that the output signal from the proximity switch has a proper ground.

4. GROUND TEST POINT. Enables meter or scope monitoring connection to the common ground point.

5. SIGNAL TEST POINT. Provides for monitoring of proximity switch ground signal output (voltage present when green light not lit, grounded when lit).

6. POWER SUPPLY MONITORING POINT. Voltage will be present from internal 27 VDC batteries or auxiliary power (see #9-10) with ON/OFF switch (see #7) in ON position.

7. ON/OFF SWITCH. The ON position routes battery or auxiliary power (see #9-10) to the power supply monitoring point (see #6). The ON/OFF switch provides power to the red and green light for testing of the proximity switches. Turn tester OFF whenever test box is not being used.

8. RED LIGHT ON LAMP. Lights when voltage is present at item #6. The red light dims when the three internal nine VDC alkaline batteries are exhausted. To test batteries, turn ON, note red light, press test switch.

9. AUXILIARY POWER POSITIVE CONNECTION POINT. External connectors are provided to power the box in the event the the internal batteries have inadequate voltage.

10. AUXILIARY POWER NEGATIVE CONNECTION POINT. For a full circuit outside power supply, there is an auxiliary positive connection.