The Problem:
You have a generator overhaul ahead, and while your current GCTs haven’t failed, 30 years of service has taken its toll on your confidence in their reliability, especially if the environment they are in is not spotless and pure. The last thing you want is to have the generator go down due to these old GCTs, and you want any replacement GCTs to last past your retirement. You think you have the original drawings, but you’re not sure if you can find them. You certainly don’t want to fabricate a new mounting for the GCTs, so a custom-designed, exact fit mounting footprint is needed. Keeping everything under control and organized during a maintenance period is critical and a huge challenge, so you want to be guaranteed that your GCTs arrive with just a little staging time – not too late and not too early, just right on schedule.

The cost of unplanned downtime is astronomical, so product quality and excellence of fit is crucial. Small quality or fit issues can quickly cause millions of dollars of problems.
“From 2011 through 2020, demand for electricity in all regions is expected to increase 8% or 9% in total, based on population growth and projections from the U.S. Energy Information Administration.” (ASCE’s 2013 Report Card for America’s Infrastructure)

“After 2020, capacity expansion is forecasted to be a greater problem, particularly with regard to generation, regardless of the energy resource mix. Excess capacity, known as planning reserve margin, is expected to decline in a majority of regions, and generation supply could dip below resource requirements by 2040 in every area except the Southwest without prudent investments.” (ASCE’s 2013 Report Card for America’s Infrastructure)

The Solution:
Your solution is Meramec’s Encapsulated Bushing-Type Generator Current Transformer.

The toroidal core is continuously tape-wound using cold-rolled, grain-oriented electrical grade silicon steel, which receives a full stress relief anneal after it is wound to its specified dimensions. The insulation used provides a durable 130°C (Class B) system throughout the entire coil assembly. The secondary winding is wound of insulated copper magnet wire over the fully insulated core with the turns equally spaced around the core periphery. Specially engineered shield windings are strategically integrated into the main secondary winding to minimize the effects of stray magnetic flux from adjacent high current conductors. The outer insulation is a molded resin rated for outdoor use. All mounting holes are cast-in aluminum hubs, which prevents mounting hardware from coming in direct contact with the resin surface. It will endure rigorous vibration and is impervious to moisture.

The EGCT is custom-designed to fit over any terminal bushing. The mounting holes encased in the resin body are located to specifically align with the all-thread rods suspended from the generator or lead box frame. The EGCT can be installed onto the bushing terminal one at a time, and locked in place with the appropriate hardware.

What makes Meramec the right choice is our customization, quality and delivery. Every CT we produce is custom-designed to your specific application. Our engineering design, our technicians’ attention to detail, and our 100% verification all contribute to the achievement of our 5 year 99.978% quality performance rating. Our customer service is paramount as well. If you are in a scheduled maintenance mode, we deliver as needed. If you are in a downtime crisis situation, we pull out all the stops to get you up and running.

Additional Features & Options
  • Other conduit openings are available – threaded up to 1.5” NPT or non-threaded holes up to 52mm.
  • Designs can be made to match existing CT characteristics.
  • Gapped cores for remanence control and transient response are available.
  • Windings may be provided with special test taps.

The Meramec Difference:
  • We are available 24/7 to support you.
  • RFQs are quickly turned.
  • Delivery performance
    • In project mode, rest assured it is delivered on time.
    • In crisis mode, we pull out all the stops to get you up and running.
  • Custom CT designs with custom mounting.
  • Known and proven product quality – install and forget.
  • Technical support that allows your engineers to focus on other issues and not the CT’s design.
  • 99.978% Quality Performance.
  • We are the Instrument CT Specialists. Instrument Transformers are what we do.




Meramec’s Rapid Response is available for rush situations. We are available to support your needs. Designs can be made to match the existing current transformer characteristics or to optimize your chosen parameters. Our products are guaranteed and backed by our 99.978% quality performance rating.

When you are in need of Current Transformers to directly replace existing units, to upgrade your system, or to outfit new equipment – Spec Meramec…When it has to be Right!