Sorry for late answer but the coil-span, number of circuits, type of jumpers, are intact as per original winding even though there are many compressor installed side by side and some of them are are rewinded by our company and all of them are almost on original ratings but got problem with this...
Hello everyone,
I have rewind a Seimens motor 250KW with exactly same data as original and motor is consuming higher ampere against original, motor details are
Atlas copco compressor
Rated ampere 445 as per name plate
Current ampere on start initially it was 515 the. Slowly rising and now it is...
Neither i change the wire size nor turns, as per user's statement they took field resistance in winter around 20°C it was 6.6OHM IN ORIGINAL WINDING rest you know
iop95,
I used three different meters for volts and amperes both shows almost same and the drive is programmed to give 23.5amp no matter whats the voltage
No there is nothing additional in excitation circuit, i can't check this right now, will check it if i can,
If i rewind the motor again should i increase it's guage and lower its resistance to 5.6OHM? Or if anyone could help me with this thing?
The copper i used is best quality available here and it says 99.99% copper so there is not a chance of copper impurity, if i change blower from 5.5hp to 7.5 hp will it lower the temperature? Motor is currently running on 18amp and after 2 to 3 hours temperature raised to 90°C
Tell me one more thing if i add one more blower on commutator side or change the original blower to commutator side will it impact good or bad? Or i should change original blower 5hp to 7.5hp
Kflan if there is any slight changes in wire guage the weight wouldn't be same as original weight is exactly same as original and when motor was original it shows 7 ohm on when motor is not running and 7.7 after hot
Tell me one more thing if i add one more blower on commutator side or change the original blower to commutator side will it impact good or bad?
Today i run motor at 18.5 amps it start at 155volts by the time goes it increases to 194 in 75 minutes (off load)
Speed remain same from 180 to 280 volts 500RPM
In the nameplate its written
440 Armature volts
600 Armature amps
180 Field volts
23.5 Amp
But RPM is 500/1200
We are running it on maximum 500RPM on load is there any problem with this?
Posting winding connections in a while
Field connections are 2 parallel
Voltage is 180 and motor starts at 175 volts but by the time goes it increases and after half an hour it reaches 280 volts 23.5 amps
SWG 14 single wire parallel connection
Will answer all the questions you guys have i just need to solve this problem ASAP thanks
Only interpol windings are original shunt and field winding are rewound,
it was in round wire originally SWG 14
Used same 99.99% copper
All the spacer below Field winding cores are intact.
Yes amperage remain same but voltage keep increasing and field temperature touching 100°C at 280Volts...
Here are some photos will share more laterhttps://files.engineering.com/getfile.aspx?folder=213524ae-228b-4144-adc5-da2d3bc444a7&file=Screenshot_2022-07-25-03-16-41-327_com.miui.gallery.jpg