User guide

25-62-31
Page 39 of 85
JUN 25/13
ARTEX PRODUCTS / ACR ELECTRONICS, INC
DESCRIPTION, OPERATION, INSTALLATION AND MAINTENANCE MANUAL
ME406P (453-6611)
SUBTASK 25-62-31-750-008
M. Current Draw Test – Item 5f
CAUTION
: EXERCISE EXTREME CAUTION TO AVOID CAUSING A SHORT CIRCUIT CONDITION,
WHICH WILL BLOW THE FUSES IN THE BATTERY PACK. THIS TEST SHOULD ONLY BE
PERFORMED BY AN EXPERIENCED TECHNICIAN/MECHANIC.
CAUTION
: ALL “ON” STATE CURRENT MEASUREMENTS MUST BE MADE WITH THE RF OUTPUT
(I.E., ELT ANTENNA CONNECTOR) LOADED WITH 50 OHMS RATED FOR 5 WATTS.
EITHER A RESISTIVE LOAD OR EQUIPMENT WITH 50 OHM IMPEDANCE PADDED WITH
A 10 DB/5 WATT ATTENUATOR. REFER TO SUBTASK 25-62-31-750-002 ON PAGE 36.
CAUTION
: ACR ELECTRONICS DOES NOT RECOMMEND MEASURING THE 406 MHZ BURST,
WHICH DRAWS UP TO 5 AMPS OF CURRENT; HOWEVER, THE AMMETER USED TO
MEASURE THE STEADY STATE CURRENT OF THE 121.5 MHZ TRANSMISSION MUST BE
CAPABLE OF WITHSTANDING A 5 AMP CURRENT DRAW OR MUST HAVE THE READING
SCALE ADJUSTED ACCORDINGLY. KEEP IN MIND THE ELT TRANSMITS A 406 MHZ
BURST WHEN THE ELT IS RESET, IN ADDITION TO A 406 MHZ BURST
APPROXIMATELY EVERY 50 SECONDS.
(1) Verify the ELT control switch is in the “ARM” position.
(2) Separate the battery pack from the ELT. See SUBTASK 25-62-31-050-001 on page 47.
(3) Install test fixture 500-0057 in the power circuit. See Figure 10. Current Draw Test Setup.
(4) Connect the ammeter and set it for the lowest possible scale.
Figure 10. Current Draw Test Setup
TEST FIXTURE
500-0057
CONNECT ELT FLEX
CABLE HERE
CONNECT TEST FIXTURE
TO BATTERY PACK PLUG
+
A
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