10/01/2013

Preventive maintenance of the bridge manoeuvring system

The bridge manoeuvring system does not require maintenance due to its design, yet it would be an advantage if the below mentioned items were checked occasionally.
Preventive maintenance of the bridge manoeuvring system

Safety Panel. Activate the "Test shut-down" and "Test slow-down" one at a time, and check that the appropriate white lamps immediately light up strongly. The test buttons should be activated (pushed) for at least 20 s in order to initiate the appropriate functions.

Bridge Emergency Button

Open the cover which protects the three emergency buttons, and activate the STOP button.

Check that the emergency stop valve (ESV) is activated and draws the fuel pumps to "0" index. Set the button back in the neutral position after checking is completed.

Check the emergency "Full" button whilst an upward regulation through the load program is ordered, i. e. when max. r.p.m. are ordered on the bridge telegraph. As soon as the load program lamp lights up to indicate that further upward regulation is blocked for a short period, activate the "Full" button. Observe that the load program lamp extinguishes and that the main engine r.p.m. immediately begin to rise. Immediately this is checked, the button must be placed in the neutral position, since the function is then working.

The third emergency button "cancelling" is best checked by activating the test slow-down or test shut-down on the safety panel in the engine manoeuvring console. Press the test button in until a slow-down takes place respectively. As soon as the main engine begins to regulate downwards, the function is cancelled by activating the cancelling button on the bridge. The main engine should now regulate upwards again in a normal manner.

The cancelling button can now be set back in the neutral position, and the cover closed over the three emergency buttons, as all functions have now been controlled.

Voltage Supply

A knob is.mounted on the Voltmeter Unit to enable all voltage groups in the control panel to be measured. Turn the knob through all 13 measuring positions and check that the voltmeter reading is always within one of the two green areas.

A reading up to 60 V is permitted in position 2, since in this case measurement takes place across the unloaded emergency supply. If the system is furnished with an emergency battery supply, its capacity should be regularly checked by placing the "Normal-battery" contact in the "Battery" position.

Now check whether the pointer of the emergency supply voltmeter in the control room manoeuvring stand remains within the green area.