Dear ScottyUK,
Q1 - Thank's for your interpretation, which seems to be in line with my question. I am now in position to try explain this to the SWBD Maker (non english) prior to the coming testing. I think it may be easier to explain it additionally by referring to for e.g. certain...
Dear colleagues, I hope someone can explain following statement in IEC 61439-1 10.10.3.1 General:
<Quote>
In absence of test at 60 Hz for currents above 800 A, the rated current at 60 Hz shall be reduced to 95% of that at 50 Hz.
<Unquote>
The Switchboards for Temperature Rise Test are rated for...
Dear colleagues, I hope someone can explain following statement in IEC 61439-1 10.10.3.1 General:
<Quote>
In absence of test at 60 Hz for currents above 800 A, the rated current at 60 Hz shall be reduced to 95% of that at 50 Hz.
<Unquote>
The Switchboards for Temperature Rise Test are rated for...
itsmoked,
Thank you for your additional comments.
It looks that even the VFD may not be necessary for the process point of view, it have several features which can be used for finetuning the process and thereby increase the efficiency of the project.
I have to trust on the Compander, Motor...
Dear colleagues,
Before closing this thred, I'd like to present my result of evaluation of Soft Starter vs. VFD for Compander in ship use.
Without going into detailed descriptions, I'd like to make summary of some main features when starting the motor (main issue):
A. VFD:
1. (+) Voltage...
Dear GreenDriv,
The Compander Maker is stating, that it is only high start inrush current which is problem, and it is not problem for the Compander itself but for the ship power network of stability point of view.
When compander is running, no control from the drive is needed, only protection...
Dear jraef,
Yes, these soft starters have been used in my previous LNG Projects for Cargo Pump and LD/HD Compressors as well.
The key issue will be the current and torque control capabilies of the drives at motor start as well as start/stop ramping of the current.
Dear colleagues,
Thank's for your valuable replies.
You listed pretty much the key items on the issue.
Again, only reason to go this path is to save some money (if possible) and still keep the needed performance of the System.
It looks that technically it should be possible taken in...
Currently in our ship project has VFD (Variable Frequency Drive) been used to start and ramp up 3.1kV/60Hz/2-pole/5400kW electric motor for Compander.
Ship power network have 4 pcs 6,6kV/3800kW/60Hz Diesel Generators whereof 3 is running when motor is started. Sufficient capacity to start the...
Dear colleagues,
In the ship specification is stated that in case the capacitive fault current exceed 5A, the neutral to be provided with resistor (resistor earthed system).
I have been looking suitable ways for calculation, but there seems to be many different ways (?) to calculate capacitive...
