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  • Users: moira
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  1. moira

    motor failure

    Hi, Humbleuser: I think, you are a credit to yourself and who ever you work for! You had your problems, but stuck it out and accomplished what you were intrusted to do! You did a GOOD JOB! Hopefully for all of us, our work can be one continuing educational process. Only a few years...
  2. moira

    motor failure

    H Humble:::: If you have other similar machines, check them! Check with operating personnel, sometimes these folks can be a tremendous asset. Your pump supplier may be able to help. MOIRA
  3. moira

    motor failure

    Hi, again, HUMBLE.: I'm not positive that they are thermal o/l switch. I'm pretty sure they are (were). If they were just a straight digital open/close verify for OK temp. of the motor then you can temp. get away with a jumper to keep this part of the PLC as seeing a good, closed...
  4. moira

    motor failure

    Hi, HUMBLEU: The two small wires in your motor originally were most probably the high heat/thermal protector. They are normally closed switches that are calibrated to go open when an abnormally high temperature is sensed in the motor. They are inbedded in one of the motor windings. You will...
  5. moira

    Combination Starters

    Hi, Jaref: Must appolige for my incorrect interpetation of the question. Thanks for the correction and education. MOIRA
  6. moira

    Motors sitting for 4 years.

    Riggspsk: I'm in aggreament with SKOGSGURRA and WAROSS base testing (insulation test and bearing conditions must be done) before any extensive and expensive break downs become necessary. If you don't want to or can't run motors; then banks of heat lamps and small blowers/fans can be set...
  7. moira

    Combination Starters

    Tulum: A/B's and other's kA ratings for their device boxes: combo breaker/motor starting relay are in many ways based on HEAT REMOVAL ability. The heat created by normal current flow thru the components of the rated boxes, etc. must be safely removed. Heat created by the identical...
  8. moira

    Motors sitting for 4 years.

    Hi,Riggspkk: 4 years is NOT that long a period of time for well made and previously maintained motors. Your biggest problem may be with the bearings of the larger size motors. I don't know your budget! Its own weight has tended to impose "flat" spots on the big ones. How much; I...
  9. moira

    motor failure

    Hi again, Humble:: You have said something about the motor sitting around for about a month. I hope that it was protected , if outdoor in bad weather? Was the motor always together as the same pump motor set? Should mention that it is always good practice to check the...
  10. moira

    motor failure

    Hello, HUMBLEU.: When you buy an unknown motor you should: 1) Make a uncoupled running test; see how it sounds, see how it turns by hand ( should have very little physical resistance, it should take some time to coast to a stop), look for cracks, loose joinery, any signs of abuse, for a...
  11. moira

    Issues with adding high-resistance system ground

    All: Having worked many years involved with both systems, it is a tought call! What are your customer's biggest electrical safety concerns? I'm inclined to give the edge to high resistance grounding. You want to have, let's say , the greatest amount amount of arc-flash protection in...
  12. moira

    Contactors welding together

    Hi,JRLAKE: From your brief report, I'm thinking the starter is a NEMA size 2 or 3 magnetic with a good bit of duty on it. A good check out of the entire control circuit is in order with particular attenion to short cycling issues. Check what voltage you are getting to the coil, its...
  13. moira

    choosing fusible resistors

    LarryG: Your posting is lacking much info; as noted by all! First thing Larry, is NO FUSES IN ANY NEUTRAL!!!! EVER!!!!! If you expect three phase power in nominal 480 VAC feeders, you must fuse each phase ( 3 fuses), one in each line for at least 175 % of caculated amperage load...
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