Question About the Emergency Diesel Generator

Professional Mariner Forum
24

Seen plenty of EDG failures. Very seldom was it to do with electrical automatic buss transfer. Most of the time it was due to operator error. As in last person to operate EDG did not restore it to automatic operation settings. On older gear 30 plus years old gear, seen auto start for engine not engage because of faulty relay (agastat timer)

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25

Not if you stay on the surface. We didnā€™t have batteries.

26

On two occasions I experienced E-gen failure to start. In both cases they were on new builds. One had passed all shipyard tests and was departing the port for transit. E-gen test was run just after the last sea buoy, just to be safe. It took two hours to find a faulty sensor preventing the generator from starting. The next occasion was similar. Again a faulty sensor in the automation. There is something to be said for primitive, got oil, fuel, air e-gen starting. Let the automation take over after the power is available.

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27

Iā€™m not an engineer but keeping the EDG ready to go on-line seems much simpler than operation of the SSDGs. Iā€™d expect EDG failures to be relativity rare in that case.

Evidently the possible failure paths are more numerous than Iā€™d imagined.

I suspect itā€™s easier to get complacent about the EDG than the SSDGs as the latter are required 24/7.

28

Do any flag states require the EDG to be tested online or with a blackout?

29

Requirement to test under load for two hours each month means it would be tested by blackout change over. Open bus tie on main swbd, e-bus blacks out, EDG starts and bus tie on e-bus side opens and EDG breaker closes. Budda bing.

Or are you implying one would have to blackout the entire ship to test the EDG? In terms of the EDG I donā€™t see the value added for that.

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30

Monthly test under load is a SOLAS requirement. Thereā€™s also a weekly test, the EDG is started and run with no load. PSC also will sometimes want to see the EDG switched over same as is done in the monthly test.

We also once did a recovery from a total blackout test - charterers requirement.

Iā€™ve never experienced any issues with the EDG that I recall, at least none in the last 20 years or so.

But with the exception of the test I only recall having the SSDG go off line unexpectedly one time and that was at anchor. Engineers were doing some work on them at the time. EDG fired up and took the load within seconds.

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