The PMS(Power Management System) controls and monitors power plant in ship. The powewr system is 440V, 3phase, 3 4440V generators and neutral flaoting earthing system. During earth fault from washing machine, the blackout occurs. PMS supplier said that blackout is reasonable action as sound...
I have read IEC 60034-1 in conjuction with motor earthing. It tells me to be earthed from motor frame in addition to earth tap on the terminal box for motor more than 100kW.
If the bonding is achieved between motor frame and terminal box, the motor frame is still required ?
Can you tell me...
I have problem with overheating in motor stater and the surface of MCCB, magnetic contactor, and cable is very hot. The insulation tube at the terminal lug is almost melted. The rating of cable, magentic contator, and MCCB are correctly selected. I took out the components to bring shop and...
6/10kV cables are installed for the power network at 6.6kW. After completing cable installation, Dielectric high Voltage Withstand Test is to be applied to cables with meggering. Test gives us to confirm the insulation of cable by recording leakage current during test. the detected leakage...
I'd like to know power consumption of 40 feet 'Reefer Container'. I have scanned Container Manufacturer's website but failed to find it. Anybody knows website or electric data for it ?
I'm involved with commissioning on 690V 3phase, IT(Unearthed system). The system has earth monitoring system, supplied by Bender. The monitoring system consists of BENDER IRDH575 monitoring insulation resistance and EDS470-12 evaluating/locating insulation.
Anybody tell me how earth is simulated...
I received short circuit calculation on the switchboard however, the short circuit level needs to be lowered in order to select Circuit Breaker with less fault current in aspect of cost.
I therefore suggest to adjust constants values such as subtransient reactance on the four generators. If...
I measured insulation resistance by Megger and it reads 5 MOhm. P.I is approximately 1.0. I believe that this value indicates poor insulation. I assume that humidities are ingressed into generator due to long term storage. I will heat it up.
If it is not humidity problem, I'd likw to know any...
I set the following figures for field protection(40)
Alarm angle : 15 degree
(Alarm)
Xa1 : 3 Ohm
Xb1 : 44.8 Ohm
Time Dealy : 7 s
(Trip)
Xa2 : 2 Ohm
Xb2 : 16.8Ohm
Time Delay : 0s
In these settings, I have tripping of ACB for Generator due to field failure. I triy to troubleshooting for it. Can...
I have read Ex Certificate showing LCIE 00 ATEX 6032. There is a descrition of 'the motor will be equipped with internal thermo sensors for category 2D to protect the insulation class of motor'. The motor is Ex nA, T3 and insulation class is 'F'.
Somesone says that motor starter should implement...
Today I started up generator but ACB for generator has been tripped due to Differential Ocurrence. The reason is that CT's ratio are different from each other, which means that CT from Generator is 1250/5A and CT from Switchboard is 1250/1A. The protection relay is Alstom P343.
I am not sure if...
I'd like set protection setting for generator protection relay but I'm not familiar with setting for Loss of exciation and voltage restrained overcurrent. What information is required to be obtained for setting and how can I calculate to set both protections ?
In order to verify THD 5% at the power network which is 690V 3 phase, I am going to measure THD. Can you tell me Harmonics Analyzer Manufacture and Model you can recommend and what should be conseration into selection of analyzer ?
For the temporary commissioning purpose I have one 10MVA, 13.8kV/6.6kV delta/star transformer with 8.23% impendace. The neutral at the secondary is solidly grounded but in this case we may not achieve safety(damage and danger to human during fault) at short-circuit.
For this reason, in general...
Can anybody tell me the easiest way to test the differential protection function for generator ? I need to see trip of generator ACB by protection relay.
I has been reported that recently Halogen lamp(300W) has been burnt when large motor starting a couple of days after replacing with new bulb. It was repeated. It has been bulited in service for 2 years.
It results from voltage drop ? or other possible reasons ?
I am preparing commissioning procedure for battery discharge test. I have read tech manual from Saft-Nife Battery. During discharge test do I record current and voltage at certain interval ? If so, what is time interval for recording ?
Why dischangre test is required for battry ?
