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  1. FreddyNurk

    Registration state by state

    Been quite some time since I was working in NT, but generally for building related services the requirement is to register with Building Practitioners Board. Electrical was not one of the disciplines required to register but structural and mechanical were. I think CPEng was required for...
  2. FreddyNurk

    Synchronizing solar,wind, and grid

    This is relatively straightforward in certain configurations now, but there's still a few caveats, and it's subject to how big the system and load is. As an example, SMA has components that are capable of being configured to run in either grid-connect or islanded with solar and batteries, they...
  3. FreddyNurk

    Dumb Contractor Request

    @Enhineyero, did they ask you for a Section 40 as well? EDMS Australia
  4. FreddyNurk

    Trip Circuit Supervision - Alarm or Trip

    So trip coil supervision is normally used when there's a risk that the coil itself has been disconnected or is otherwise non-functional. It is done as a positive operation check (i.e. confirm that the trip circuit is intact and operational) as opposed to just hoping that the circuit integrity...
  5. FreddyNurk

    Power Factor Improvement For Generators

    waross has a longer winded (better? sorry waross...) explanation but the summary is, if you're the only source on your network, then your load defines the power factor and the required reactive power. If the required reactive power is within the capability curve of the generator, and the load...
  6. FreddyNurk

    Small Generator Protection - Backup for Grid Faults

    What's the load and arrangement look like? I've seen VCO used for feeders in islanded systems as 'normal' protection practice using pure overcurrent for feeders doesn't behave so well with tiny machines. That scenario may not apply to what you're doing, particularly if you're connected to a...
  7. FreddyNurk

    ALF and ISF in Current Transformers

    That's because they don't really mean the same thing. One is used for selection of CTs for protection purposes, the other for metering and measurement. Whilst the function and behaviour of the CT is the same for both purposes, the requirements are different for the two applications, and the...
  8. FreddyNurk

    Device that Data Logs Generator Output?

    Something like this might work https://aemc.com/products/power-analyzers/power-pel105 Perhaps if you advise why you're looking at capturing data off the generator as well? Is it a pilot product that you're doing validation on, or is it an existing piece of equipment with issues? Some of us...
  9. FreddyNurk

    Motor starting from Generator(s)

    waross' approach is pretty much de rigueur for sizing generators for starting motor load, if it isn't it probably should be. One aspect I'll add, as I've seen what I'd consider as surprisingly large sets without an excitation boost or PMG system, is that it needs to be called out when dealing...
  10. FreddyNurk

    [DG SET] What is the difference between DG Crank & DG Run relay?

    To expand on the responses here, there's a couple of options on what is happening, and it depends on the specific configuration. Run relay is generally a permissive to run, as both waross and Tug have indicated. Start relay engages the starter motor (generally via a solenoid). In some cases...
  11. FreddyNurk

    Generator Protection setting - key points

    Strictly speaking that doesn't really include the first two options asked about, only the third. I've also dealt with plenty of applications where overcurrent is used and coordinated on a per set basis as far as is practicable given the size of the load and the size of the generator. It's not...
  12. FreddyNurk

    Generator Protection setting - key points

    Single Set would generally be overcurrent, overload, undervoltage, overvoltage, underfrequency, separate overspeed as a minimum. Parallel set would extend to reverse power as an absolute minimum. Sync check depends on the system, if there's any possibility of an operator closing out of sync...
  13. FreddyNurk

    CAT3616 with Woodward 2301A; paralleling to grid without governor droop enabled

    I am aware of use of a 2301A as a load bias device for Caterpillar generators, as I understand it one can't just use a 4-20mA or similar output, but put a 2301A in load share mode and off it goes. The context I am aware of was parallel isoch in isolated networks (supervising controller varies...
  14. FreddyNurk

    Generator tripping while paralleling

    waross, you are correct that they do the same thing, it appears the difference is quadrature droop allows the voltage to droop as the power factor gets further away from unity, cross current does not. I've managed to locate the document I was using for reference in the difference between the...
  15. FreddyNurk

    Generator tripping while paralleling

    At that size there's multiple ways of doing load and var sharing. Once such way is as waross has stated, Quadrature sharing, another is cross current compensation (which also requires a separate CT), the third way with modern controllers is to let them do the VAr sharing, no CT required but...
  16. FreddyNurk

    How to Get Emergency Diesel Generator Started automatically?

    They normally have a speed bias output in one form or another (CAN, 4-20mA, 0-5V etc) that will interface with whatever's on the engine, to be able to synchronise, and parallel load share with other similar connected units. There's obviously a minimum threshold for capability and in all my...
  17. FreddyNurk

    How to Get Emergency Diesel Generator Started automatically?

    Bumpless transfer probably isn't the best term for what I'm referring to. The Deif units (I'm familiar with the older GPC series rather than the newer AGC150) are mostly capable of synchronising, hence the use of bumpless transfer. Fast Open-Transition as you note may cause issues. EDMS...
  18. FreddyNurk

    How to Get Emergency Diesel Generator Started automatically?

    waross, in this case as IRstuff as alluded to, the Deif will likely handle mains failure, and can be configured to auto-start on loss of mains. However, as you note, it either needs a separate ATS, or the Deif needs to monitor the appropriate bus and either trip the mains breakers or the mains...
  19. FreddyNurk

    Islanding detection on grids with distributed energy resources

    The fundamental is that the plant may be islanded without CB1 opening, it could be something upstream that causes a blackout and CB1 won't open, rather it'll remain closed and reconnect when the network returns. There's often no obligation on the utility to put a UV element on the CB, and if...
  20. FreddyNurk

    FIBER OPTIC CABLE SIGNAL TRANSMISSION

    For this application I'd use something like this, it's purpose built for such applications, and only needs two cores. Importantly, it also complies with the relevant protection standards, assuming from your context that this is a protection application. EDMS Australia
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