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"If you increase excitation, the generator's voltage increases. The generator will then deliver its peak current (crest of the sine) earlier than before - simply because the voltage is at its peak earlier. can you explain why increasing the excitation brings the crest of the sine wave earlier...

Thankyou, so the equipment i am talking about is a dual fed induction generator I understand that the generator can export energy from both the stator and the rotor. I understand the principles of changing the rotor frequency to compensate for lower rotor speeds to stillproduce 50 hz. I have...

Hopefully someone can explain this to me. In a ac system that can import and export power. what is going on with the waveform of current and voltage as it moves from importing to exporting power. it cannot be a simple reversal of current flow, which would be easy to understand as its AC. im sure...

We have some large motors that have covers over the slip rings, the covers are removable using a standard panel key, should the covers have a bonding wire between the covers and the generator? I know electrical panel doors should be bonded? If a bonding wire is required what size should it be...

Hi, I want to measure the current output from a UPS. I seem to remember that there is a reason that you can't use a standard current clamp on inverter outputs as it will not give a true reading. I am assuming that the output from the ups will be some sort of PWM waveform? could somebody please...

Thanks for your help! I have taken your advice and found a suitable rotary switch and was also able to find a small mcb that may or may not be necessary. I had seen that 16A outlets can be protected by a 20A fuse, which seems crazy as it is not unusual to see power tools etc with 0.75 cable on...

In this instance i want to use a rocker switch rated at 16A to supply a 16A commando socket for an adapter box .The protective device is 16A. I cant find a 20A rocker from our designated suppliers that will cope with the inductive load of the pump i want to control . I have found a 16A one that...

Thanks for the reply Jraef. For future reference when i am selecting components like relay/switch contacts etc should I use components that have contact ratings equal to or above the rating of the circuit breaker? or do i only really need to consider the expected load. do you know where this...

Sorry i meant to say should the switch rating be over that of the breakers that protects it

Hi sounds like a simple question. is ok to use a switch rated at 16a in a circuit protected by a 16 a breaker, or does the switch rating need to be under that of the breaker, the expected load is only 6A

sorry just to be clear an rcd on the primary of an auto transformer would provide protection to secondary circuits as they are electrically connected An rcd on the primary of a normal transformer ie two electrically isolated coils would not provide protection to the circuits on the secondary...

Am I correct in thinking that if a rcd feeds a transformer, then anything connected to the secondary of the transformer will not be protected by the rcd and another rcd is required to provide protection

No unfortunately I think that is a little beyond my capabilities I kind of understand what Harmonics are but that is about the limit of my abilities. This cannot be a design error as it is one of many and the others aren't doing it just running out of ideas and not getting support we need from...

Thanks for the replies, Please forgive my descriptions below if they sound a little unprofessional So this issue we have is on a generator system, I belive the type of generator is an asynchronous generator, the power electronics on the rotor side of the generator from what i can gather convert...

Hi Am I correct in saying that the snubber circuits on the power transistors of an AC drive help to prevent undesired switching of the power transitors. we have a fault and I am considering whether it is worth changing the snubber modules?

Hi, I work for a company who has proposed for me to make alteration to a 24v dc control circuit. I have looked at the proposed alteration and can see from the drawings that the current circuit has a 50A breaker feeding several other smaller breakers between 4A and 10A. These feeds are routed...