We are on the process of planning our new fabrication plant and the we need to have 6pcs. 500KVA transformers. The existing High tension on the area is 30,000V. I am not sure of how much is the capacity of the line in terms of Amperage. Upon calculation, each one of my 500KVA transformer would...
Hi Ozmosis,
Thanks for the translation, i've tried using an online translator but it gave me different meaning. I was thinking the generator is really small for my compressor. But I need to defend this by electrical formula or simulation so I can convince my boss. Also, the problem, is that it...
Hi Bill,
Thanks for the quick response. Below are my answers:
1.) Yes the generator's speed drops upon compressor start up (delta to star) and also when air loading. But in between this transition, the generator is at the right speed and voltage output.
2.) Yes when at nominal load, the...
I just want to add this info, perhaps someone can help me pinpoint where the verdict is. The genset that we are using is just a customized genset. Somebody from the company is clever enough to advice the manager to have a genset made from junks. The V8 Mercedes-Maybach engine came from Swiss...
Hi Bill thanks for the specs, but the problem is how to defend this one, the compressor in combo with the 400KVA has been working for a while (at least for a month). Once can easily say it was really under specs since when the compressor loads the 10Bar tank, then the generator really is being...
Dear Masters,
I am new to the world of motors, but more or less I can stand the principles. May I ask on how to measure and how to test this big motor that we have for our compressor? Suddenly the start up draws around 500-600A which causes our mains to trip. But when I test the compressor, I...
Hi Warross and other professionals,
I've managed to check the insulation resistance on the exciter stator field and exciter rotor windings and the result is 0.12M on the stator and on the exciter rotor is only 0.02M.
The Main field is about 3-4M and I suspect i don't have problem with this...
Hi Waross,
Yes I have, I measured the resistance of the exciter stator and its only 2.5ohms. I think I need to check it out with my megger, what could be the minimum allowable resistance?
Thanks,
Chris
Hi,
May I ask your technical advise as to how can I test if my exciter stator coil and exciter rotor is still in good shape? I took the resistance reading from the exciter stator and the reading is only 2.5ohms. I understand from my previous readings that normally the stator coil is around...
Hi Guys,
Got the programming manual from Bernini Engine Control, they have some funny trick on programming though. I've adjusted the Over Frequency Alarm to 65Hz and checked also the over voltage alarm to 500V.
After this, I slowly adjusted the engine speed until I get 1800 rpm and continuosly...
Hi edison123,
Oops I missed that one, from the catalog i gathered from internet, the 380V/50Hz (1500rpm,), will be 416V/60Hz at 1800rpm..... guess we got the wrong generator. :(
Scenario is that again, we have 60Hz here in our area, my boss bought a 22KVA UPS for all the computers and he has...
Hi edison123,
Yeah i understand that, on the voltage regulator, there is a provision for 60Hz operation, alternator's plate tells 50hz with an rpm of 1500. If I adjust to 1800rpm, then from the motor formula I should get 60Hz. But one thing I am not sure of is the mechanical design limits. If I...
Guys,
I have this stamford alternator from a MOSA generator. The motor plate says 50Hz but I want to operate to 60Hz. Can I adjust the speed of the engine, jumper the voltage regulator to 60Hz and adjust parameter in the engine control? Can this procedure give me 60Hz? Thanks
Hi Panter,
Thanks, good to know I'm not the only one using this HFG... Guess I am stuck with this problem if I cannot justify enough to buy a 20KVA VFD....
Hi Bill,
I tried isolating the 110V control supply for the relays and timers. I used a fixed normal line from the shop and hooked it up on the control side.
I've also modified the circuit and put one relay to delay the pumping action while the machine performs star-to-delta transition.
The...
Hi Compositepro,
That is also one possibility, but we are using 2 types here in the fabrication shop, one is metabo equipped with overheat and speed control, one is these bosch high frequency grinders. The specification is limited to 200Hz only, but the result of the operation via 60Hz causes...
Hi Edison123 and Bill,
Thanks a lot for sharing your expertise. That was my first idea before, to put a VFD on the motor and exciter, but I was also in doubt, maybe there are other cheaper solution. Thanks to this HF Gen, that I have known masters in this field.
I agree, this generator is a...
Hi jcarr,
We have two sets of this HF generator, and each one should handle at least 18pcs for small angle grinders and at least 10 for the big ones. My boss preferred to use this HF grinders because there are no consumables since they are brushless.
But I am faced with this problem operating...
Hi Bill,
I've checked the pressure release valve, and it is properly working. In the machine, you can press a pneumatic button to check the back pressure on the pump, and it is down to zero before the pump, rolls back again.
Since all the relays are 110V AC, and there are no...
