Section III. GENERAL MAINTENANCE - TM-5-6350-264-14-P-50025

TM 5-6350-264-14&P-5

NAVELEX EE 181-AA-OMI-060/E121 SA-1955

T.O. 31S9-2FSS9-1-5

Section III. GENERAL MAINTENANCE

the Actuating Magnet Assembly and the Bias Magnet

5-4. MAINTENANCE ACTION. The extent of direct and

Assembly. Inspection and service are provided for the

general support maintenance is governed by the

enclosure. Periodic testing of the Balanced Magnetic

Maintenance Allocation Chart (MAC), Appendix B. The

Switch is not scheduled because the J-SIIDS is

MAC provides for on-site test and replacement of the

maintained in continuous operation.

PC board, Actuating Magnet Assembly and Bias Magnet

Assembly. On- site test and adjustment are made on

Section IV. REMOVAL AND REPLACEMENT OF MAJOR COMPONENTS AND ASSEMBLIES

5-5. REMOVAL AND INSTALLATION PROCEDURES.

f. To install a new Actuating Magnet Assembly,

turn the assembly so the notches in the end of

a. To remove the PC board, tag and disconnect

the housing face the same direction as the

the wires from TB1. Remove two screws that

notch in the Magnetic Switch Assembly housing.

secure PC board to the housing. Remove the

Align the screws holes in the inner half of the

PC board.

Actuating Magnet Assembly with the screw

holes in the mount- ing surface.

Insert and

b. To install new PC board, orient the board so

tighten two screws to secure this half of the

that the terminal strip is on the side away from

assembly to the mounting surface. Place the

the Actuating Magnet. Secure the board to the

outer half of the Actuating Magnet Assembly

housing with two screws. Connect the wires to

over the inner half. Ensure that the notches in

TB1.

the housing are aligned. Insert and tighten two

screws to secure the outer half of the assembly.

To remove the Bias Magnet Assembly, remove

the two screws that secure the Bias Magnet

g. After removal and replacement of major

Assembly to the PC board. Remove the Bias

components or assemblies, calibrate the BMS

Magnet Assembly.

for proper operation. Disconnect wires from

TB1-1 and 2. Set multimeter to ohms and

d. To install a new Bias Magnet Assembly, put it in

connect leads to TB1-1 and 2. With door or

place on the PC board. Start the two screws

window closed, meter should indicate less than

that secure it, but leave these screws loose so

50 ohms. Open the door or window 1 1/4 inch

the bias magnet can be calibrated.

(3.175 cm) or more. Meter indication should

change to an open circuit or infinity. Connect the

e. To remove the Actuating Magnet Assembly,

meter leads to TB1-5 and 6. Meter should

remove the two screws from the outer half of

indicate more than 100,000 ohms. Depress the

the assembly. Remove the outer half of the

TAS arm. The meter indication should change

assembly. Remove and keep the two screws

to less than 50 ohms. Connect the wires to TB1

that secure the inner half of the Actuating

and install the cover.

Magnet Assembly to the mounting surface.

Remove the inner half of the assembly.

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