Murray MPD Main Breaker Replacement Guide

Murray MPD main breakers, load center, electrical ratings, mounting configuration, lugs and retention hardware.

Table Of Contents
  1. Understanding MPD Breakers
  2. Comparing Murray Breakers
  3. Identify the Murray Breaker Model
  4. Check Compatibility
  5. Siemens Replacement Options
  6. Breaker or Panel Replacement?
  7. Locate an MPD Breaker
  8. Popular Murray MPD Circuit Breakers
  9. Murray MPD Main-Breaker FAQ
  10. Murray MPD Main-Breaker Glossary

Need a Murray MPD Main Breaker?

Get a Breaker Quote

Understanding MPD Breakers

What Is a Murray MPD Main Breaker?

Finding a Murray MPD main breaker replacement takes more than matching the amperage printed on the breaker handle. Before selecting a new breaker, you must determine the load center, electrical ratings, mounting configuration, lugs and retention hardware. Although Murray panels are still in use, the company no longer produces branded load-center equipment. Original, surplus and reconditioned breakers may still be available.

murrary mpd main breaker

Comparing Murray Breakers

How MPD Differs From Murray MP-T and MH-T Breakers

MP-T breakers are full-size branch breakers. MH-T models include tandem and other space-saving branch-breaker configurations. MPD breakers are panel-specific main breakers.

Murray familyGeneral applicationReplacement approach
MP-TFull-size branch circuitsInvestigate documented Siemens QP applications
MH-TTandem or space-saving branch circuitsInvestigate documented Siemens QT applications
MD-T and MD-TRLoad-center main breakerApplication-specific
MPDTwo-pole load-center main breakerApplication-specific

Learn more in Relectric’s complete Murray breaker replacement guide.

A Murray-to-Siemens branch-breaker cross-reference shouldn’t be used to choose an MPD main breaker. A Siemens QP breaker may be similar to an MP-T branch-breaker application, but that doesn’t make it an MPD replacement.

Relectric’s Siemens QP breaker guide provides more information about QP branch-breaker construction and applications. Also see the Murray MH-T breaker replacement guide and Siemens QT tandem-breaker guide for tandem and space-saving replacement information.

Identify the Murray Breaker Model

Identifying Murray MPD Main-Breaker Models

Start by recording the complete catalog number printed on the existing breaker. Check the breaker label for:

  • Complete catalog number Number of poles Ampere rating Voltage rating Interrupting or AIC rating Terminal and conductor information
Next, locate the load-center label. It may be attached to the inside of the door, an enclosure sidewall, the dead front or near the wiring diagram. Record the complete panel catalog number.

The label shows the main breaker, maximum bus rating, system voltage, short-circuit current rating and compatible breaker types. Photograph the complete label for reordering information. Also photograph the existing breaker, conductors, lugs, bus connection and retaining hardware.

Check Compatibility

Murray MPD Main-Breaker Characteristics

murrary mpd main breaker

Siemens Replacement Options

Is There a Siemens Replacement for a Murray MPD Breaker?

Siemens acquired Murray’s electrical distribution product business and later discontinued Murray-branded equipment. This history explains why Siemens products are often investigated when replacing Murray breakers.

However, the Murray MPD breaker replacement process isn’t as simple as changing the Murray prefix to a Siemens prefix. The Murray main breaker replacement must be selected for the specific load center and application.

A possible Siemens replacement should be checked against:

– The complete Murray load-center catalog number
– The original MPD catalog number
– The panel’s approved breaker information
– The electrical ratings
– The bus and mounting construction
– The required lugs and retaining parts

Siemens’ Murray-to-Siemens cross-reference guide can provide a starting point, but a cross-reference isn’t an automatic authorization to install the suggested breaker. Don’t assume that two breakers are interchangeable because their handles show the same amperage or because their cases have similar dimensions. Relectric carries Murray molded-case circuit breakers and other hard-to-find electrical equipment. Provide the complete breaker and load-center information when requesting assistance.

Breaker or Panel Replacement?

When to Replace the Entire Murray Load Center

A breaker-only repair can make sense when the load center is in good condition and a properly documented breaker is available.

Complete load-center replacement is the better choice when the bus is damaged, corrosion is present, essential hardware can’t be found or the right main breaker is unavailable.

Replacement can also provide more capacity for modern loads, AFCI or GFCI protection, surge protection, solar equipment, generators and electric-vehicle charging.

Compare the cost of locating an obsolete breaker with the condition and expected service life of the entire panel. A breaker replacement won’t correct a deteriorated bus, undersized service or obsolete enclosure with unavailable internal components.

Locate an MPD Breaker

Finding a Murray MPD Main Breaker

The best replacement search begins with complete equipment information. Provide the breaker number, panel number, electrical ratings and clear photographs when contacting a supplier.

Relectric can help you locate original, surplus or reconditioned Murray equipment and investigate a documented replacement. After gathering the identification details listed above, request a breaker quote.

Popular Murray MPD Circuit Breakers

The following Murray MPD part numbers are available through Relectric. Always verify the complete catalog number, electrical ratings, mounting arrangement and load-center compatibility before ordering.

Part Number Description
MPD2150 Murray MD-T molded-case circuit breaker, 150A, two-pole, 120/240V and 10 kA interrupting rating.
MPD2150KH Murray MD-HT molded-case circuit breaker, 150A, two-pole, 120/240V and 22 kA interrupting rating.
MPD2150RH Murray MD-HTR molded-case circuit breaker, 150A, two-pole, 120/240V and 22 kA interrupting rating.
MPD2175 Murray MD-T molded-case circuit breaker, 175A, two-pole, 120/240V and 10 kA interrupting rating.
MPD2175KH Murray MD-HT molded-case circuit breaker, 175A, two-pole, 120/240V and 22 kA interrupting rating.
MPD2175RH Murray MD-HTR molded-case circuit breaker, 175A, two-pole, 120/240V and 22 kA interrupting rating.
MPD2200 Murray MD-T molded-case circuit breaker, 200A, two-pole, 120/240V and 10 kA interrupting rating.
MPD2200KH Murray MD-HT molded-case main circuit breaker for load centers, 200A, two-pole, 120/240V and 22 kA interrupting rating.
MPD2200RH Murray MD-HTR molded-case circuit breaker, 200A, two-pole, 120/240V and 22 kA interrupting rating.
MPD2200R Murray MPD2200R circuit breaker listed by Relectric in its miniature circuit-breaker category. Confirm ratings and application from the breaker and equipment labels.

Murray MPD Main-Breaker FAQ

Are Murray MPD breakers still manufactured?

Murray-branded circuit breakers are no longer actively manufactured. Original new-old-stock, used and reconditioned MPD breakers may still be available.

What is a Murray MPD breaker?

A Murray MPD is a legacy two-pole main breaker used in compatible Murray load centers. It protects and controls the power supplied to the panel bus.

What replaces a Murray MPD main breaker?

The replacement is application-specific. There isn’t one universal breaker that replaces every Murray MPD model. Selection depends on the load-center number, original breaker number, electrical ratings, bus, mounting, lugs and retaining hardware.

Can a Siemens breaker replace a Murray MPD breaker?

A Siemens product may be appropriate in a documented application, but compatibility must be verified through the complete Murray panel and breaker catalog numbers. Physical fit alone doesn’t establish compatibility.

What are MPD2150 and MPD2200 breakers?

MPD2150 and MPD2200 are catalog numbers associated with the Murray MPD main-breaker family. Confirm their ratings from the original labels and reliable product documentation rather than interpreting the catalog-number digits by themselves.

Is a Murray MPD the same as an MP-T breaker?

No. MPD is a main-breaker family. MP-T breakers are generally full-size branch breakers. MP-T replacement guidance shouldn’t be used to select an MPD main breaker.

Can I replace only the MPD breaker?

A breaker-only repair may be practical when the panel bus, terminals, enclosure and hardware remain in good condition and a properly documented replacement is available.

When should the Murray load center be replaced?

Consider complete replacement when the bus is burned or pitted, corrosion is present, essential parts aren’t available, the correct main breaker can’t be found or the panel no longer meets the facility’s electrical requirements.

Can I replace an MPD main breaker myself?

Main-breaker work should be handled by a qualified electrical professional. Line-side components may remain energized even when the main breaker is off.

Murray MPD Main-Breaker Glossary

Term Definition
AIC Ampere interrupting capacity, indicating the maximum fault current a breaker can safely interrupt under specified conditions.
Bus Conductive metal within the load center that distributes power to installed breakers.
Catalog number The manufacturer’s complete model identifier used to determine ratings and compatibility.
Classified breaker A breaker evaluated for use in specifically identified equipment produced by another manufacturer.
Interrupting rating The maximum short-circuit current a breaker is designed to interrupt safely.
Line side The breaker terminals or components connected to the incoming electrical supply.
Load center An enclosure containing a bus, main protection and branch-circuit breakers.
Main breaker The breaker controlling and protecting the power supplied to the load-center bus.
MPD A legacy Murray two-pole main-breaker family.
New-old-stock Older equipment that hasn’t been used but remains in inventory after regular production ended.
Retaining hardware Brackets, clips, screws or other parts that secure a breaker in the equipment.
Short-circuit current rating The maximum fault-current level an assembled piece of equipment is designed to withstand under specified conditions.