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Recent content by ShooterBoter

  1. ShooterBoter

    Transformer Relay VT inputs

    Well, if you (or your client) don't care about the measuring being wrong then I don't understand your issue. Assuming of course you don't have any directional protection (pure over current IOC and TOC; these protection functions don't care about the voltage/angle) But not quite sure what ratio...
  2. ShooterBoter

    Transformer Relay VT inputs

    What is the transformer vector group? What is your aim with the relay, i.e. at what fault scenario should the relay pick up?
  3. ShooterBoter

    CT - Marshallinb Box and Test Terminals

    A diagram says more than 1000 words...please draw one. If the disconnect terminals should be open or closed depends on where in the circuit they are located.
  4. ShooterBoter

    # phase power LL vs LN

    "In addition, the phase of the power is not correct in your calculations. Use the difference of the phases of voltage and current, not their sum." This is why you have to use the conjugate of the current, but you always add the angles. (22A @ 20 degrees)*=22A @-20 degrees
  5. ShooterBoter

    # phase power LL vs LN

    Ok, I gave it a try, anyone else?
  6. ShooterBoter

    # phase power LL vs LN

    You wrote that VLL = √3 x VLN. Well, there's you fundamental error. The correct way of putting it should be: |VLL| = √3 x |VLN|. See what I'm aming at? Example: VLN= 230V∠0º VLL= 400V∠30º You stated that "VLL = √3 x VLN": "400V∠30º" = √3 x 230V∠0º, as you can see this is not correct...
  7. ShooterBoter

    # phase power LL vs LN

    Hmm, sorry for my previous reply, thick fingers on a small keyboard is what caused that... Any how; S=VLN x IL ∠∅ Where VLN=Line to neutral voltage IL=Line current ∅=Angle between line to neutral voltage and line current The 3-phase apparent power is; S3P=3 x VLN x IL ∠∅ As you stated we can...
  8. ShooterBoter

    # phase power LL vs LN

    Ok, here it goes: 1) S=Vp x I ¼∅
  9. ShooterBoter

    Highest rating for 11kV switchboard.

    Not that I advocate the Schneider switchgear, but it does exceed current rating, it's up to 5000A. Link
  10. ShooterBoter

    Highest rating for 11kV switchboard.

    Schneider-Electrics PIX-H switchgear is one. Don't know if they have any references to offshore, you'll have to ask Schneider.
  11. ShooterBoter

    3 Phase electric power and load calculation

    Well, he/she asked for kVA...so the equation still holds but with wrong term; "P" should be changed to "S".
  12. ShooterBoter

    Unbalance delta load connected to star source

    @Skogsgurra "If it is a wye winding - the ampere-turns do not agree so well..." Why wouldn't the amp-turns match in this case?
  13. ShooterBoter

    Wiring schematics software

    Take a look at Elmaster, Link SB
  14. ShooterBoter

    Need help on REF542plus

    Oops, I totally forgot about this thread... I haven't checked the connection via ethernet Cable, but I know that a Dsub9F-Dsub9F serial cable will work. I can't remember if it's a strait or a null modem Cable I use - need to check this. Kind regards, SB
  15. ShooterBoter

    Substation batteries

    Usually the battery manufacturer will define a "end voltage". Discharging the battery below this point will probably cause damage to the battery. If you discharge the battery way below this pint you'll not be able to charge it to full capacity again.

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