MAGNETIC SWITCH 



TEST BUTTON 

 TOGGLE SWITCH 

 INCLINOMETER 



FIELD OF VIEW 



COMPASS ASSEMBLY 



hrr 



Figure M-13. 



Main components of the Geodyne 

 current meter. 



cording Current Meter" should be used as a ref- 

 erence to supplement these instrtictions. The fol- 

 lowing si^ecial tools are required: 



Vise-grip pliers. 



Open-end box wrench. 



10-foot-pound torque wrench. 



Screwdriver. 



1. Checking the exterior of the current 

 meter — 



Step 1. Remove the meter from its shipping 

 case, and stand it rotor end down on wooden 

 platform provided in the case. As a safety pre- 

 caution, always lash the meter to the bulkhead, 

 stanchion, or the overhead. Secure line around 

 pressure case, not to the tie rods. 



Step 2. Visually check the exterior of the 

 instrument for rotor or vane damage or bent 

 tie rods. If instrument appeai-s to be damaged, 

 it should not be used. 



StejJ 3. Remove the tape from the rotor and 

 the vane, and inspect rotor and vane for proper 

 bearing play. 



The 5-inch red tube positioned on the lower 

 end cap is the On-Off magnetic switch. When 

 the On-Off switch magnet is in place, it causes 

 the internal switch to open and stops the re- 

 cording mechanism in the current meter. 



2. Opening the current meter. — To install the 

 battei-y, load film, and check out the instrument, 

 the jDressure case cylinder must be removed from 

 the meter. 



Step 1. With vise-grip pliei-s, hold the tie 

 rod, and with open-end box wrench, loosen nut 

 on lower end of rod. 



Step 2. Remove nuts, lock-washers, fiat 

 washers, and fiber washers from the three tie 

 rods, and lift off the upper cap assembly with 

 tie rods. Put the assembly in a place where the 

 tie rods will not get bent accidentally. 



Step 3. Remove the on-ofl' switch magnet, 

 then lift the pressure-case cylinder straight up 

 and off the lower end caji and the internal mech- 

 anism. Place the pressure case where it will not 

 roll and accidentally injure persomiel or be 

 damaged. 



Step 4. Place the on-off switch magnet in its 

 holder to keep the instrument from operating, 

 and lash the meter to the bulkhead, a stanchion, 

 or the overhead to prevent damage or personnel 

 injury. 



3. Checking the batteiy. — Power for the cur- 

 rent meter is supplied by a 12-volt, dry-cell bat- 

 tery. These batteries are designed specifically 

 for the current meter. At NAVOCEANO, 

 meters usually are shipped with battery in- 

 stalled, but the batteiy always should be checked 

 each time the current meter is operated. 



Step 1. Unsnap the battery-holding strap, 

 slide the batteiy out of its compartment, and 

 unplug the nine-pin battery connector. 



Step 2. Check battery with voltmeter. If bat- 

 tery voltage is not at least 11.5 volts under a 

 100-ohm load at ambient room conditions 

 (70° F.), the battery should be replaced. A re- 

 placed battery should be plainly marked by 

 writing "old"' in several places on the case. 



Step 3. Check the new battery, as in step 2 

 above, before installing. Make sure that battery 

 connector is completely seated and that lead 

 wires are placed in clearance space above 

 battery. 



Stei5 -1:. Check to ensure that battery is con- 

 nected properly by pressing red test button on 

 tojj of meter. Secure battei-y-holding strap 

 fastener. 



i. Setting the sequence timer. — The sequence 

 timer is located on the field of view platfoim. 

 The timer operates on a 1-hour cycle, and a 

 lobed cam which is installed on the 1-hour shaft 

 determines the number of 50-second data records 



Change 1—1970 



M-11 



