Adding a small burden to existing CT

[DRWeig]

Power & Protective Relaying Friends,

Customer has existing 5-amp instrumentation circuit from CT's. I have a split-core 5-amp to 0.333VAC (safe CT) device that will add about 350 micro-VA of burden when connected to its load. Both price and convenience make this a good solution. I don't have to buy a set of 2000:5 CT's (the little split-cores are cheap) and I don't have to shut down the board to install.

Can you imagine the addition of this small burden causing a problem in any situation? Most of the CT's I've seen in place are rated at least a couple of VA.

Thanks in advance for your opinions...

Old Dave

 

[buzzp]

I would say there should be no concerns. If the original designer made the burdens marginal such that 350u makes a difference then you will probably have bigger problems somewhere down the line. Now if this will be added in parallel (for some strange reason) then you might have some issues but I can't imagine a case where there would be paralleled instrumentation on one current transformer.

 

[DRWeig]

Thanks BuzzP,

It just always feels better to have somebody else agree with one's opinion on new stuff.

It's not a parallel issue, customer is adding some third-party metering to do some demand profiling. It's a nice little CT he found, made by Magnalab.

Good on y'all,

Old Dave