Pennsylvania Transformer Technology, LLC
Transformer Replacement Parts

OEM Replacement Parts for Load Tap Changers,
Oil Circuit Breakers and More

Pennsylvania Transformer Technology (PTT) is the authorized supplier of OEM replacement parts for McGraw-Edison, Cooper Power and Pennsylvania Transformer load tap changers, and for McGraw-Edison, Cooper Power, Federal Pacific and Pennsylvania Breaker circuit breakers. PTT stocks contacts, gaskets, O-ring kits, reversing kits, hydraulic pump kits, coils and other wear parts, and can ship emergency breaker components quickly. Call (724) 873-2100 or complete the form below and include your model and nameplate details for a quote.

Fun fact: The McGraw-Edison 397D On-Load Tap Changer (LTC) is a durable, reliable workhorse that can be maintained without specialized equipment or complex PLC training—and it’s still actively manufactured by the original OEM in the same facility where it was developed. Alongside the McGraw 396, 550, and V series, it remains an invaluable grid asset, backed by dedicated OEM field employees. We’re proud to support these tap changers and the skilled men and women who keep them running every day.

Load Tap Changer (LTC) Replacement Parts

As the original manufacturer behind McGraw-Edison, Cooper Power and Pennsylvania Transformer designs, PTT supplies exact-fit replacement parts and maintenance kits for these tap changers. Our engineering group holds the historical design and test data for these units.

Is the McGraw-Edison 397D still manufactured?

Yes. The McGraw-Edison 397D on-load tap changer (LTC) is still manufactured by the original equipment manufacturer in the same facility where it was developed. PTT's Power Solutions Division supports it with OEM parts and dedicated OEM field employees.

Durable designs with practical maintainability

The 397D combines reliable operation with a serviceable design that does not require specialized equipment or complex programmable logic controller (PLC) training for maintenance. McGraw-Edison 396, 397, 550 and V series tap changers remain valuable grid assets, supported by experienced field technicians who help keep this equipment operating reliably.

LTC models supported and common parts stocked
LTC model Typical parts and kits
McGraw-Edison 550LS / 550HS Main dial kits, main and stationary contacts, door and panel gaskets, O-ring kits
McGraw-Edison 550BLS / 550BHS Main and stationary contacts, reversing kits, collars, pins, shafts
McGraw-Edison 550C / 550CS Main and stationary contacts, gaskets, hardware
396B, 397D, 496B Contacts, O-ring kits, collars, miscellaneous hardware
996 Contacts, gaskets, reversing kits

Parts we stock for load tap changers

  • Main dial kits
  • Door and panel gaskets
  • Main contacts
  • Stationary contacts
  • Reversing kits
  • O-ring kits
  • Collars
  • Pins
  • Shafts
  • Hardware

High Voltage Circuit Breaker Replacement Parts

PTT stocks parts and kits for McGraw-Edison, Cooper Power, Federal Pacific and Pennsylvania Breaker oil circuit breakers, from hydraulic pump kits to contact blades and stationary shoes.

Circuit breaker models supported
Series Models
McGraw-Edison / Cooper Power AHE, AHJ, AHP, ALP, RHE, RHF, CF37, CF40, CF48, CG38, CG48, CHG50, EPB72, VAC-G
Pennsylvania Breaker PB72, PB145, PB245

Parts we stock for circuit breakers

  • Hydraulic pump kits
  • O-ring kits
  • Motors
  • High-pressure relief valves
  • Trip and close coils
  • Resistors
  • Interrupter baffles
  • Contact blades
  • Stationary contacts
  • Stationary shoes
  • Hardware

Breaker Mechanisms: OA3, OA4 and M01

PTT's Power Solutions Division can rebuild or supply complete new breaker mechanisms, including OA3, OA4 and M01.

Emergency? Fast shipping is available.

How to Order Replacement Parts

  1. Find the nameplate on your tap changer or breaker and note the model and serial number.
  2. Note any part number, or take a photo of the part.
  3. Send the details with our quote form below.
  4. A PTT parts specialist confirms fit and returns pricing and lead time.

Request a Parts Quote

YOUR CONTACT DETAILS

EQUIPMENT & PARTS DETAILS

Thank you! Your message has been sent.
Unable to send your message. Please fix errors then try again.

Replacement Parts: Frequently Asked Questions

Find answers about ordering OEM replacement parts for load tap changers and oil circuit breakers, including what to send us and which models we support.

Where can I buy McGraw-Edison load tap changer replacement parts?

PTT is the authorized supplier of replacement parts for McGraw-Edison, Cooper Power and Pennsylvania Transformer load tap changers. Send your model and nameplate details, or call (724) 873-2100, and a PTT parts specialist will quote the contacts, gaskets, kits and hardware you need.

Request a parts quote.

What information do I need to order a replacement part?

Provide the equipment model, the serial number from the nameplate, and any existing part number or a photo of the part. With those details PTT can confirm exact fit against its original design records.

Send your nameplate details.

How do I identify my load tap changer model?

Check the nameplate on the tap changer for the model and serial number. If the nameplate is missing or unreadable, send photos of the unit and its major components, and PTT can help identify it using its original McGraw-Edison, Cooper Power and Pennsylvania Transformer design records.

Send photos with a parts request.

What is in a load tap changer maintenance kit?

A load tap changer maintenance kit groups the parts that wear during routine service, such as main and stationary contacts, gaskets, O-rings, pins and hardware, so crews have everything on hand for a planned outage. Exact contents vary by tap changer model.

See supported load tap changer models.

Can I get replacement parts for an obsolete oil circuit breaker?

Yes, for the McGraw-Edison, Cooper Power, Federal Pacific and Pennsylvania Breaker models PTT supports, including AHE, AHJ, AHP, ALP, CF, CG, RHE, RHF, PB72, PB145 and PB245. Contact PTT with the nameplate data to check availability.

View supported circuit breaker models.

Can PTT rebuild or supply breaker mechanisms such as OA3, OA4 and M01?

Yes. PTT's Power Solutions Division can rebuild existing breaker mechanisms or supply complete new mechanisms, including the OA3, OA4 and M01. Send the breaker model and nameplate details, and a PTT parts specialist will confirm the right mechanism and provide a quote.

Learn about breaker mechanisms.

Does PTT install the parts it supplies?

Yes. PTT field service technicians based in Canonsburg, PA are trained in transformer and circuit breaker repair, refurbishment and installation, including load tap changer and breaker parts replacement.

Explore PTT transformer service solutions.

Do you supply parts for transformers made by other manufacturers?

PTT's Power Solutions Division services transformers and high-voltage breakers from other original equipment manufacturers (OEMs). Parts availability depends on the make and model, so contact the parts team with your nameplate details to confirm what PTT can supply.

Contact PTT sales and support.