service report island sky english

8/3/2019 Service Report Island Sky English

1/8

Service Report

Service at: Istanbul and Samsun / TurkeyCustomer:Period: Oct 8 to 13, 2008Alternator: DIDBN 131 I/10 Number: 8103336 C003

Scope of work: Assembly and start-up of DG I

The passenger vessel ".." in the port of Istanbul on 09/10/2008.


2/8

We found the alternator in the following condition on the October 9,2008:

The stator was fixed to the foundation with the pins in place. The rotorwas coupled to the drive machine; the bearing and the end shield were

mounted.

Since there was no grease on board and the bearing has not yet beengreased, the bearing end cover and the grease slinger had to be

removed.


3/8

An insulation test was performed on the stator winding, and all powerand control cables on the stator and rotor sides were connected.

When doing so, we found one of the auxiliary terminal boards to bebroken.


4/8

The board was fixed temporarily using a cable tie.

We routed and fixed all cables in the alternator and connected both thevoltage regulator and the resistor integrated into the excitation.


5/8

In the meantime, we installed the PT100 for the bearing temperaturemonitoring in the alternator and integrated a temperature alarm circuit

into the existing alarm control. Furthermore, we installed two resetbuttons with signal lamps in the engine control room and the control

system in the engine room, in addition to the existing alarm control. Weset the warning threshold to 75 C.


6/8

When the grease arrived on Friday afternoon, we greased the bearingand tried to assemble the alternator completely. However, since we didnot have enough time due to the delay for obtaining of the grease, we

discussed the problem with the port agent who then organised a flight to

Samsun for Saturday.

The alternator was assembled completely on Sunday. We rotated themachine by hand prior to the first start, and three visible damage points

were found on the exciter system. They had evidently been caused whenthe end shield was mounted during the assembly of the alternator.

Insulation tests and resistance measurements were performed for thewinding; no abnormal conditions were found.

The points mentioned above were coated with insulation paint.


7/8

The start-up was performed as follows:Dry run in the excited state for approx. 20 minutes.

The bearing temperatures increased to 26 C. The machine was stoppedand operated with excitation at 60Hz.

I1/K1: 16VDCI2/K2: 141VDCUH1/UH2: 95VACUH1/UH3: 186VACWH1/WH2: 99VACU-V-W: 3x 440VAC

The alternator was operated in this state for a longer period until thecrew was able to rectify a problem with the motor control.

Subsequently, the alternator was synchronised with alternator DG II andsubjected to load. Since different currents could be measured at thesame load, the no-load voltage was adjusted on alternator DG II. It

differed from the voltage measured on alternator DG I by 3V. A loosecontact was detected on the setpoint potentiometer of DG II. A jumper

was installed on the voltage regulator between "s" and "t", and thevoltage was adjusted on the regulator. The next dry runs in parallel

operation were completely properly; each alternator was loaded with alittle over 300kW at approx. 500A.

We shifted the entire load to alternator DG I, opened the drive-end cover

of DG II and measured the bearing temperature. This measurementyielded a temperature of 60 C.

DG I was operated at a load of more than 600kW for 2 hours, and thetemperature was measured cyclically. The last measurement yielded a

bearing temperature of 40 C.I1/K1: 24.7VDCI2/K2: 144VDC

UH1/UH2: 99VACUH1/UH3: 196VAC

WH1/WH2: 102.5VACU-V-W: 3x 441VAC

Since non-one on board could find the PT100 monitoring unit which wassupplied a few years ago after damage to the bearing of DG II, no

temperature monitoring could be installed for DG II. We gave instructionsto the chief electrician on how to set up such a monitoring unit and how

to integrate it into the existing system. A circuit diagram was created andhanded over as a PDF file, and is also attached to this report. The

following components must be sent to the Island Sky:1 pc. PT100 tripping device2 pcs. relays with 2 changeover contacts


8/8

We gave one PT100 to the chief electrician and showed him where andhow to install it.

The defective setpoint potentiometer of DG II must be replaced. After thereplacement, the jumper between "s" and "t" on the voltage regulator

must be removed again, and the voltage must be set accordingly.

There is an option to bring the actual temperature with the 0 10Voltsignal of the PT100 tripping device to the engine control room. It would

make sense to install a measure instrument like this to give the crew thechance to react as soon as possible if there is a problem on the

bearings.

Best regards

Daniel Patzek, service engineer.Oliver Wanka, service engineer.

service report island sky english

Documents