11
OPERATING THE LOG
 
A. OPERATING INSTRUCTIONS
 
11A1. Position distance transmitter load switch. The distance transmitter load switch (Figure 11-1) is mounted in the upper right corner of the master transmitter indicator. This switch is set in the heavy load position when there are more than two repeaters operating, or when the dead reckoning tracer (DRT) and dead reckoning analyzer (DRA) are in operation. Otherwise, it is in the light load position at all times. This switch is used for making a rough adjustment to vary the

Figure 11-1. Distance transmitter load switch.
Figure 11-1. Distance transmitter load switch.

maximum torque output of the follow-up motor. The variable rheostat is employed for a fine adjustment of the output of the follow-up motor.

11A2. Energizing the system. Turn the electrical switches controlling the 1Y, 2Y, and 3Y circuits on the interior communications (I.C.) switchboard and the conning tower repeater switch on the action cutout (A.C.O.) switchboard to their ON positions.

11A3. Opening the sea valve. Raise the deck plate above the sea valve. Turn the sea valve handwheel in a counterclockwise direction as far as possible to fully open the sea valve gate.

  11A4. Lowering the rodmeter. (See Figure 10-7.) The rodmeter will be in one or two positions: the normally housed position as shown in Figure 10-7, or the fully housed position. To lower the rodmeter, turn the hoist crank counterclockwise until the rodmeter is in its extended, or operating position. Keep the hose clear of projections and chain links.

11A5. Venting the system. Do not vent the system when the ship is submerged. Such a practice will damage the bellows mechanism due to the fact that the pressure increases approximately 1/2 pound per square foot for each foot of submergence, and it is practically impossible to open or close the dynamic and static valves simultaneously so as to keep the pressures equal on both sides of the bellows.

For best results the ship should be stationary. The purpose of venting the hydraulic system is to remove any air that may be trapped in the system. Vent the hydraulic system in the following manner. Turn the

Figure 11-2. Maneuvering cocks and drain cocks
in secured position.
Figure 11-2. Maneuvering cocks and drain cocks in secured position.

maneuvering cocks and drain cocks from their secured position (Figure 11-2) to the venting position (Figure 11-3). Keep the valves in this position until a clear stream of water,

 
127

Figure 11-3. Maneuvering cocks and drain cocks
in venting position.
NOTE: After opening upper air collector vent cock slowly and simultaneously open both static and dynamic drain cocks as shown. When free of air, simultaneously close both drain cocks.
NOTE: After positioning maneuvering cocks, open upper air collector vent cock as shown. Leave open until static and dynamic drain cocks are closed; then close this vent cock.
Figure 11-3. Maneuvering cocks and drain cocks in venting position.

free of spitting is obtained; then turn the maneuvering cocks and drain cocks to their operating positions (Figure 11-4). Turn the maneuvering cocks first in going to, and in going from, the venting position.

11A6. Securing the log. Whenever the ship enters port, the log system should be secured.

Figure 11-4. Maneuvering cocks and drain cocks
in operating position.
Figure 11-4. Maneuvering cocks and drain cocks in operating position.

This is done in the following manner: Turn the hoist crank in a clockwise direction until the top of the rodmeter is level with the marker plate, indicating that the tip of the rod is clear of the hull. Keep the hose clear of projections as the rodmeter is raised. The rodmeter may be raised to its fully housed, or

  secured, position by turning the crank until the top of the rodmeter hits the stop at the top of the hoist. Turn the valves to their secured position as shown in Figure 11-2. Turn the 1Y, 2Y, and 3Y switches on the I.C. switchboard, and the conning tower switch on the A.C.O. switchboard to their OFF positions.

11A7. Draining the hydraulic lines. If the ship is to be in port for an extended time, or

Figure 11-5. Maneuvering cocks and drain cocks
in drain position.
Figure 11-5. Maneuvering cocks and drain cocks in drain position.

if it becomes necessary to make repairs on the hydraulic lines, the fines are drained in the following manner: Raise the rodmeter to its fully housed, or secured, position. Position the valves and vent cocks as shown in Figure

Figure 11-6. Maneuvering cocks and drain cocks
positioned for filing hydraulic lines.
Figure 11-6. Maneuvering cocks and drain cocks positioned for filing hydraulic lines.

 
128

11-5. With the valves in this position, the water will drain from the lines through the drain maneuvering cock.

11A8. Filling the hydraulic system. If the ship is equipped with a new log installation, or if the hydraulic system has previously been drained, fill the hydraulic system in the following manner: Lower the rodmeter to its

  extended, or operating, position. Position the valves and vent cocks as shown in Figure 11-6. When a full stream of water, free of spitting is obtained from the upper air collector valve, close this valve. Tap the bellows housing to facilitate the removal of air from the bellows chamber, and when a full stream of water is obtained from the static and dynamic vent cocks, close these drain cocks. Vent the system thoroughly as described in Section 11A5. Turn the valves to the desired position.
 
129

Previous chapter
Previous Chapter
Sub Log Home Page
Sub Log Home Page
Next chapter
Next chapter


Copyright © 2013, Maritime Park Association
All Rights Reserved
Legal Notices and Privacy Policy
Version 1.11, 28 June 05