Figure 4-17.--Mk 23 Mod C-3 control cabinet.

Figure 4-17.--Mk 23 Mod C-3 control cabinet.

converter or a 24-volt dc supply and to the master

reversed to counterclockwise as viewed from the

unit.

south end of the gyro axle as it was in other ballistic

compasses. The direction of the vertical torque is also

reversed.

POWER CONVERTER

The Mk 27 gyrocompass system (fig. 4-18) consists

The power converter is used to convert 115-volt,

of a master unit, an electronic control cabinet, and a

60- or 400-Hz, single-phase power to 24-volt dc when

power converter.

24-volt dc is not available.

MASTER UNIT

OPERATING THE MK 27 GYROCOMPASS

The master unit contains the compass element

The control panel located on the electronic control

and receives its electrical and electronic support from

cabinet contains all the operating controls necessary

the electronic control cabinet. The master unit also

for operating the compass. Instructions for starting

contains a bellows assembly to allow for temperature

and securing the compass are listed on an instruction

variation, a card viewing window, a cager diaphragm,

plate located near the electronic control cabinet. For

an electrical connector, and the fluid-filling nozzles.

additional information on starting and stopping the

compass, refer to the manufacturer's technical

ELECTRONIC CONTROL CABINET

manual.

The electronic control cabinet houses the control

WATCH STANDING

panel, power supply, servoamplifier, latitude

compensation circuit, and alarm circuit. The

Watch-standing procedures for the Mk 27

electronic control unit has plug-in connectors, which

gyrocompass are basically the same as for the Mk 23

are used to connect the unit to either a power

gyrocompass. Indicator lamps for the power available