Hello
Is there any code requirements for using 24 volts and 120 volts on two separate set of contacts of same control relay? I want to keep them separate but I am being questioned by some guys working along with me.
Can I operate two transformers; 3MVA 440 Volts, 50 Hz, 6% impedance and 4MVA 440volts, 50Hz, 7% impedance; in parallel?
If yes what will be the percentage load sharing by each of them?
Can anybody give me an Idea that why capacitor reforming is needed in the cases where a drive has been sitting on shelf for too long? I want to know what changes in capacitor if it's not been used for a long time? Is this required only for the capacitors which are connected to power circuit or...
My question is regarding IR value of an alternator which is at it’s commissioning stage. It’s a 38 MVA, 11KV alternator and was stand still for many years at some other site. The megger values which I am getting is 1.3 Mega Ohm Phase to ground for all three phases and 2.7 Mega ohm for Phase to...
How does field weakening affects the incoming AC power to the DC drive? Is there any benefit of having field weakening speed below the nominal speed of the motor? As an example I have a DC motor with 268 RPM at 750 volts and 2500 Amps. When I checked the programming of the drive I found that...
Hello Everybody
I have a question regarding encoder voltages. I have an encoder with input voltage 24 volts. Output of this encoder is connected to two devices PLC and Optoisolator. Output of Optoisolator is further connected to two different PLCs.
If I leave encoder output unconnected and...
Few years ago I came across same kind of problem on 1800 KW, 11KV motor. It happened during running. Suddenly there was huge variation in current and motor became noisier. We got that repaired but manufacturer of motor suggested that whole end ring should be replaced.
Here is another one in which it shows that N7:138 is a BCD filehttp://files.engineering.com/getfile.aspx?folder=63b4e30e-59fc-4d11-bf96-baadec3b439f&file=scan0002.jpg
Sorry about pic.
I thaught all pages will upload at same time. But here is the pic. for that rung
http://files.engineering.com/getfile.aspx?folder=d175277d-fa9f-4a48-bfd1-13c829fec2ba&file=scan0002.jpg
Hello Everybody
I am having difficulty in understanding a logic in PLC 5 and I have attached print outs for the same. Data files D56:15 and D56:16/0 to D56:/3 is triggering outputs O: 014 and O: 015. These outputs are used to transfer set points or other parameter values to a servo controller...
It's really nice to know about effect of cable capacitance on it's megger value. There has been some discussion on cable length, so just want to mention that cable in question is around 700 ft long and is of 500 AWG. When I saw 2 mega ohms of megger values I was thinking about changing it. But...
Hello Everybody
Recently we had yearly shut down in the plant and as planned we got our substation checked. This was done by world wide reputed company and it involved checking of some underground 4160 volts cables. While checking they found one of the 4160 volt cables giving 2 Mega ohms meggar...
