Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

bus transfer scheme

bus transfer scheme

bus transfer scheme

Can any one give me any sort of information or consulting on how to set up a GE D25 multifunction IED to use in a bus transfer setup.  My partner and I intend it to monitor two step down transformers and three breakers.  This is to ensure there is nol oad loss in the event of a fault or power failure on one of the transformers.  We want to monitor and control the system using the D25 instead of several protective relays.

RE: bus transfer scheme

I wasn't able to find any info on the GE D25 IED on the GE website, other than a generic mention in a brochure on substation automation - this shows the D25 interconnecting individual feeder relays and other IEDs with a LAN.

Does the D25 have the logic and measurement capability to perform the functions required?  If it does, then it should be a straightforward exercise to program it to sense breaker status and/or bus voltage loss and to initiate a bus transfer.  Even if it needs the inputs for the individual bus relays to do the measurement functions, the logic could reside in the device to do the actual switching.  More data needed to properly evaluate the scheme.

RE: bus transfer scheme

If you are talking about a medium-voltage system, you will need to decide how fast a transfer you really want.  If there are large motors on this system, you should consider monitoring the bus voltage to delay transfer until residual voltage has decayed to a safe value.  If you really need a fast transfer, you will have to do a synch-check so you can momentarily parallel the sources (for a normal transfer)if they are generally in phase.

You also need to implement logic for re-transfer depending on how you want it to work, and a way to designate preferred source versus alternate source if you are going to operate single-ended.

Be careful with the residual voltage.  If you transfer too quickly you can damage your motors and/or trip on overcurrent from out-of-synch operation.

The D25 probably can be programmed to do this, but it might be easier in a PLC.  

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close