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Recent content by jburn

  1. jburn

    Electric System Fault Calculations - MVA Method

    Hi All Type in "short Circuit Calculations" into the Google search engine, and you will find a lot of information on this topic. Below is information from one web site, I found, where you can purchase a book at a reasonable cost. I am not selling or promoting the book...
  2. jburn

    Electrical Rating of Single Phase Relay?

    I obtained the UL number and looked it up on the UL web site. The Catalog number of the soft starter is listed on the UL web site, under the number given. All it tells you is that it is a Solid state motor controller.
  3. jburn

    Electrostatic Oil Cleaners for Hydraulic Systems

    I am looking for information on electrostatic oil cleaners, for use on a hydraulic oil system. We are having problems with the build up of varnish in the system. The hydraulic system is used on a steam turbin and operates at 1200 PSI. Can anyone point me to a good sourse of technical...
  4. jburn

    Hi, I am looking for informat

    Hi, I am looking for information on electrostatic oil cleaners, for use on a hydraulic oil system. We are having problems with the build up of varnish in the system. The hydraulic system is used on a steam turbin and operates at 1200 PSI. Can anyone point me to a good sourse of...
  5. jburn

    Electrical Rating of Single Phase Relay?

    Hi, Thanks for your response to my post. I have contacted the manufacture of the relay, GRUNER AG, and this was their reply. "As the relay is used as a bypass and is only carrying the voltage and current and does not switch it, there is no problem to use it for this application.&quot...
  6. jburn

    Cost Reduction by Adding HRG Units

    busbar, Sorry it makes you nauseated. But that's life in the industrial corporate world today. Just trying to get all of the ammo I can. There are more good projects than $$ to go around. Those that build the best case first, gets the prize!! Have a good day.
  7. jburn

    Cost Reduction by Adding HRG Units

    HI, Several folks on this forum, plus discussions with other electrical engineers, has convinced me of the need to install High Resistance Grounds (HRG) units on all of my 480 Volt and 2400 Volt ungrounded delta substations. I have been allow to purchase one unit, so far...
  8. jburn

    Electrical Rating of Single Phase Relay?

    HI, I would like some opinions on this. A Mfg. rates a small single pole relay at 40A/250VAC. The applalication the relay is used in, the current the contact will normally see is vary low, on both make and break, maybe less that 1 amp. Its used to bypass a set of SCR's, which will be fully...
  9. jburn

    480 Volt 3 PH Soft Starter By Pass

    GGoss Thanks for the offer of help. I would perfer not to name the make and/or model of the soft start controler (SMC)that we are using. I am receiving help and support from two different manufactures of SMC's, including the manufacture of the one I am using, as well as from some power...
  10. jburn

    480 Volt 3 PH Soft Starter By Pass

    RJF, and d23 The ground alarm system is a home grown system but using all standard components. I do not have HRG on my 480 volt Delta unit subs, so I used a ground detector made by Erickson Electrical Equipment. The Erickson unit gives me a dry contact. I hooked up the Erickson to the...
  11. jburn

    480 Volt 3 PH Soft Starter By Pass

    RJF The SMC units do have a fault code. We are getting "Phase Loss/Loss of Load" and sometimes "Phase Imbalance". In talking the some of the design engineers from two companies who make SMC's, isolation transformers, or reactors in front of the SMC,s will not help. One...
  12. jburn

    480 Volt 3 PH Soft Starter By Pass

    tmahan I have a system in place that capatures, time stamps, and stores every ground event in a database, on all of my substations. I can look at the past history of ground activy on any substation. Every time I had an SMC drop off line, I had recorded ground activity on the substation...
  13. jburn

    480 Volt 3 PH Soft Starter By Pass

    jraef Both Allen Bradley, and Cutler Hammer have units with an internal bypass. The AB SMC-3 unit has an internal bypass. The Cutler Hammer models S751, and S801 both have an internal bypass.
  14. jburn

    480 Volt 3 PH Soft Starter By Pass

    dpc & Mark Thanks for the replies. You have been a big help. In my case, the SMC I am using has internal bypass contact around the SCRs. The SCRs are not being damaged, the SMC units just drop off line. The additional bypass contactor I plan to install will be used to get the SMC electronic...
  15. jburn

    480 Volt 3 PH Soft Starter By Pass

    busbar, Thanks. I have worked with ungrounded systems for over 30 years myself, in several different industrial plants. (23 years in this one) I purchased a copy of Beeman's book years ago, and it is well used.

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