Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations SDETERS on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Recent content by Gr8blu

  1. Gr8blu

    Poor Power Factor

    A couple of questions to be sure we understand what you're asking: 1) Is the filter acting on the drive output (between drive and motor, for example) or on the drive input (between drive and utility, for example)? 2) How much load (current) is being applied - both in actual amperes and in per...
  2. Gr8blu

    Optimal value of Sub transient reactance - Generator

    Subtransient reactance impacts the ability of a generator to work as much like a utility as possible so system loads can work normally when running on a generator set. The objective of an alternator selection process is to get as close to a utility capability as possible. From a generator...
  3. Gr8blu

    power factor issue

    The value of the correction is dependent on load. If your caps are on (with welder and/or grinder operating), the utility sees a "corrected" power factor close to unity (but still lagging). If the caps are disconnected and the machines are operating, the utility sees the actual lagging power...
  4. Gr8blu

    ALSTOM MX3VIR016A PROTECTION RELAY PROGRAME

    To program Alstom relays, you typically use Alstom's Micom software, which allows you to configure the relay's settings, protection functions, and communication parameters. In other words, unless you have the (more or less) proprietary Micom software, you cannot directly configure the default...
  5. Gr8blu

    roast my resume

    As part of the tailoring process, you might want to quantify how good your solutions were for a given issue. As an example - the very first "task" in the most recent job states that you were involved in coordinating internal material specifications with current industry standards and that you...
  6. Gr8blu

    Small dc brushed electrical motor format "280"?

    All your listed equipment manufacturers in the original post are Japanese or Chinese. I would start by seeing what the Japanese national standard (JIS) documents have to say about naming conventions for rotating electric machines. Just took a peek at the Ningo Bo website. It would appear that...
  7. Gr8blu

    EIT v. Junior v. Intermediate v. Senior

    In my experience, it is not time in service that equates to a specific title - with the exception of EIT (engineer in training). If applied for, an engineering student can become an EIT by first passing the FE (Fundamentals of Engineering) exam, then entering the workforce in an engineering...
  8. Gr8blu

    Small dc brushed electrical motor format "280"?

    Most non-North American manufacturers use the IEC standards as their basis, with some national exceptions/additions. The Japanese have their own national standards (JIS) that are more-or-less based on the IEC standard now in effect. The "280" designation referred to by the OP is a dimension...
  9. Gr8blu

    LO/TO - remote circuit breaker

    Not sure - but the AHJ might be a bit sticky on remote lockout because the requirement is for BOTH lock out AND tag out. That typically means a tag co-located with the lock - regardless of whether there is another tag at the "user" end of the line (near the equipment, or in this case the...
  10. Gr8blu

    RPM range for air duster/blower

    The air pressure requirement is going to depend (a LOT) on the kind of snow and the amount of snow. Think about how hard it is to move wet leaves vs dry leaves - or small branches, instead of dry twigs. Snow can be fairly deep, and wet, and sometimes covered in ice (either from melt or from...
  11. Gr8blu

    Rotating equipment engineer in EPC vs SITE or Plant

    From what I have encountered, the biggest difference between being an engineer with this type of background while engaged in EPC activities vs as a "site" engineer is that the EPC is focused on getting bits and pieces to show up on time and - hopefully - work together long enough to get off the...
  12. Gr8blu

    VFD Configuration

    I have to assume you did not order the machines yesterday, based on your expected delivery time frame. What should have happened is that you receive at least TWO items of documentation well before the machines are expected to show up (usually no more than 4 weeks after the order was received by...
  13. Gr8blu

    Motors

    Chocolatecat: Synchronous speed is found using the following relationship (for AC machines ONLY): (synch speed in RPM) = 120 x (input frequency of current waveform, in hertz) / (number of poles) Asynchronous machines - which means both squirrel cage and wound rotor induction designs - tend to...
  14. Gr8blu

    Electric motor terminal blocks

    Depends on the voltage rating. For machines over 1000 V, typical connection is to have bus bar drilled for each phase (or polarity, if it's DC). For connections to lower-voltage devices/equipment, it varies widely. Most reputable manufacturers use terminal blocks for sensors, etc. but perhaps...
  15. Gr8blu

    INVERTER MOTOR (YASKAWA GA700) VIBRATE WHILE DECELERATION

    Hmm. OP indicates some vibration during acceleration, but more during deceleration. Is the interval the same - or does deceleration take a lot longer (i.e. a coast-down approach)? Might be as simple as sitting on (or at least near) the system resonant frequency longer during the deceleration...

Part and Inventory Search